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Polling Power: User feedback from the 7F 2020 Digital Conference

By Team-CCJ | March 18, 2022 | 0 Comments

A valuable feature of Power Users conferences is audience polling, which was pioneered by the 7F Users Group a few years ago. The steering committee and presenters use polling to ask owner/operators for their opinions on industry trends, the information needs of attendees, etc. Because the feedback is virtually instantaneous, it can identify where clarification or more detail is required on a particular subject during the presentation of interest.

Below are some of the polling questions asked during the 7F 2020 Digital Conference. The responses both characterize the audience and provide a snapshot of what your industry colleagues are thinking on topics of importance to owner/operators. Users can access presentations from the conference, a plethora of recorded technical presentations, and ask questions on the forum at the Power Users website.

Audience

How many times have you attended a 7F Users Group conference (including this year)?

My first meeting, 46%
Two years, 20%
Three to five years, 21%
Six or more years, 13%

How would you rate your level of 7F knowledge?

Newbie, 14%
Rookie, 10%
Intermediate, 37%
Seasoned, 25%
Expert, 4%

What is your primary role?

Maintenance manager, 12%
Plant manager, 10%
Maintenance engineer, 16%
Turbine engineer, 28%
Asset manager, 11%
Other, 22%

How often do you interact with power traders or dispatchers?

Multiple times a day, 7%
Daily, 22%
Weekly, 12%
Rarely, 29%
Never, 29%

General

What is the average age of your 7F and steam-turbine units based on COD?

Less than 10 years, 15%
10-15 years, 24%
16-20 years, 48%
More than 20 years, 13%

Operations

What system/component gives you the biggest headache, or impacts reliability the most, on your unit(s)? Check all that apply.

Valves (for example, gas, compressor bleed valves, etc), 45%
Instrumentation (for example, transmitters, T/Cs, etc), 38%
Protection systems (for example, haz-gas detection, etc), 14%
Inlet filtration system, 4%
Covid-19, 12%
Starting system (for example, static starter, etc), 7%

Three years into the future, how do you see your CCGT operating profile changing?

More starts, fewer hours, 50%
More starts, more hours, 13%
Fewer starts, fewer hours, 5%
Fewer starts, more hours, 16%
No change, 15%

Three years into the future, how do you see your CCGT operating and ramp profiles changing?

More part-load operation, more ramping, 65%
More full-load operation, less ramping, 6%
More full-load operation, more ramping, 9%
More part-load operation, less ramping, 3%
No change, 16%

Which type of flexibility would you choose if you could upgrade your plant today?

Higher maximum output, 17%
Lower minimum output, 31%
Faster ramping, 5%
Faster startup, 12%
All of the above, 35%

Plant managers, maintenance managers/engineers, turbine engineers: If you had the ability to cost-effectively cycle overnight versus turndown, would you want to cycle?

Yes, 29%
Absolutely not, 49%
Maybe, 22%

Traders, asset managers: If you had the ability to cost-effectively cycle overnight versus turndown, would you want to cycle?

Yes, 41%
Absolutely not, 37%
Maybe, 22%

Which type of generating unit do you think the more flexible CCGT displaced to produce additional megawatt-hours?

Less-flexible CCGTs, 21%
Simple-cycle GTs, 36%
Steam turbines, 17%
All of the above, 26%

How would you react if your trader/dispatcher asked you to cycle between 2 and 4 a.m.?

No way, 26%
Are you crazy? 21%
OK, as long as power payments make up for the increased maintenance cost, 54%

What was the cause of your last failed start (pick one only)?

Valves, 23%
Static frequency converter, 3%
Burners and nozzles, 7%
Controls, 22%
Instrumentation, 20%
Hardware, 8%
Excitation and generator, 14%
Other, 4%

What concerns you the most at your site for forced-outage days (pick one only)?

Transformer, 19%
Instrumentation, 29%
Rotor, 15%
Bearings, 7%
Steam-turbine unavailable, 19%
Other, 11%

What is your most recent annual unit/block start/stop count on average?

Fewer than 100 start/stops per year, 67%
100-200 start/stops per year, 33%
More than 200 start/stops per year, 0%

In the last 10 years, what start/stop count trend are you experiencing?

Minimal or no change, 56%
Up to 50% increase, 29%
Roughly doubled, 11%
More than doubled, 3%

Which 7F HGP TIL most keeps you up at night?

  2045, 7F AGP Stage 3 bucket tip shroud creep, 40%
2181, Stage 1 nozzle creep degradation model, 23%
2006, 7F and 9F Stage 3 bucket airfoil distress, 17%
Other/none, 20%

Maintenance

What rodent issue have you seen the most?

Cable damage in cable tray, 27%
Wire damage in electrical cabinets, 38%
Insulation damage on piping, 15%
Other, 20%

Do you currently use adjustable rigging in your lift planning for turbine rotor or case removal?

Yes, 66%
No, 34%

Combustion

How familiar are you with gas-turbine combustion?

I’m a flame-stability expert, 5%
I’m pretty good with what runs in my units, 42%
I know the difference between a DLN 2.6+ and DLN 2.6, 27%
Harry Potter’s wand must be involved, 20%
Gas turbines have combustors? 7%

What is your biggest concern when it comes to combustion operability?

Tuning, 24%
Hardware, 22%
CDM and T/C health, 17%
AutoTune, 15%
Cold weather, 17%
Nothing, my unit runs well, 6%

Have you experienced fuel-nozzle damage?

Yes, 56%
No, 44%

What was the cause of the fuel-nozzle damage?

Quat operation, 8%
Fuel contamination, 28%
Other, 45%
Unknown, 19%

If it was quat operation or unknown, are you changing your quat limits seasonally?

Yes, 13%
No, 86%

Do you have issues during cold weather with high-dynamics alarms that require operator response?

No, 45%
Rarely, 41%
Frequently, 14%

Generators

What is your most common unplanned stator repair/upgrade finding during an outage?

Endwinding dusting/greasing or resonance repair, 69%
Belly-band tightening (or new belly-band install), 8%
Stator rewedge, either full or partial, 23%
Stator core looseness, 0%

What is your most common unplanned field /rotor repair/upgrade finding during an outage?

Slot content (amortisseur spring) migration, 35%
Main lead cracking or separation, 8%
Field turn shorts, 49%
Field ground, 8%

Does your site or HQ/fleet have a spare/exchange 7FH2 field?

Yes, 21%
No, 79%

How much time is on the outage schedule for generator rotor removal and replacement—including setup and tear down?

Less than one day, 7%
Two days, 28%
Almost one week, 48%
Too long, 17%

Auxiliaries

Have you converted to electric actuators on your gas control valves?

Yes, 13%
No, 87%

Are you planning to convert the hydraulic actuators on your gas control valves to electric?

Yes, 11%
No, 57%
Don’t know, 32%

Rotors

How well do you know RLE (rotor lifetime extension)?

  Extremely well. We currently are in discussions and formulating a plan, 35%
Have discussed it with our engine representative, 24%
Know what the acronym stands for, 35%
Don’t know about RLE, 7%

What’s your rotor maintenance plan?

Exchange rotor, 29%
Lifetime extension, 32%
New rotor, 12%
Not decided/do not know, 27%

Is your rotor affected by TILs 1971 and/or 1972?

Yes, 46%
No, 20%
Not sure, 31%
It was, 3%

Is your turbine rotor maintenance hours- or starts-based?

Hours, 52%
Starts, 16%
Multiple units, some with both 27%
Was hours, now starts, 4%
Was starts, now hours, 1%

Do you have maintenance factoring calculated in your DCS logic?

Yes, 14%
No, 37%
Not sure, 16%
Tracking outside the DCS, 33%

Are you planning on conducting 7F rotor maintenance in the next five years?

Yes, based on GER-3620 guidance, 57%
No, 29%
Learning more before deciding, 14%

Exhaust system

How often do you inspect your exhaust-frame flex seals?

HGP interval only, 47%
Annually, 50%
More frequently than annually, 3%

Lubrication

How long does your oil last?

Five years or less, 10%
Six to nine years, 31%
More than nine years, 60%

How many hours do you lose annually because of an oil-related failure?

  Less than 12, 81%
12 to 24, 5%
24 to 48, 9%
More than 48, 5%

What are your MPC values?

Less than 15, 77%
15 to 35, 20%
More than 35, 3%

Does your lab report the MPC hold time as required?

Yes, 13%
No, 28%
Not sure, 59%

What type of lube oil do you use?

Mineral groups 1 and/or 2, 58%
Synthetic hydrocarbon groups 3 and/or 4, 26%
PAG, 16%

Have you used an aftermarket turbine-oil additive?

Yes, 31%
No, 69%

Do you use a varnish-removal system?

No, 30%
Yes, rotating on several units, 33%
Yes, full time, 37%

When did you install your varnish-removal system?

Following a failed lab result, 60%
Following an onsite failure, 28%
With a new charge of oil, 12%

Have you changed the type of lube oil in your gas turbine?

Yes, 29%
Considering it, 20%
No, 51%

What type of evaluation was done prior to changing the type of oil?

Full technical evaluation, 60%
Lube-oil supplier performed the evaluation, 18%
Relied on the experience of others, 22%

7F plants share best practices

By Team-CCJ | March 14, 2022 | 0 Comments

The 7F Users Group and CCJ are working together to expand the sharing of best practices and lessons learned among owner/operators of large frame engines. One of the user organization’s objectives is to help members better operate and maintain their plants, and a proactive best practices program supports this goal. Consider submitting to the 2022 Best Practices Awards Program: Deadline April 1.

Below are some 7F entries in the program receiving Best Practices Awards. They speak to work done by your colleagues at 13 simple- and combined-cycle generating plants. The more than two-dozen best practices are likely to offer one or more ideas for improving safety and performance at your facility. Consider attending the upcoming 7F Users Group in Dallas: May 23-27.

Barney Davis Energy Center

KPI index for water chemistry

Barney Davis Energy Center, Corpus Christi, Tex, implemented an EPRI-recommended water-chemistry KPI (key performance indicator) index. The plant’s original analyzers were updated and more instruments were installed, reported Plant Manager Jay Langley. Two dissolved-oxygen analyzers were added, plus one sodium analyzer; four silica analyzers were replaced.

All of the new analyzer readings were added to the DCS. KPI-index action alarms, Levels 1 and 2, also were added to the DCS in accordance with EPRI recommendations. An action plan was developed to guide operators when an alarm level is reached.

When conducting water-chemistry tests with manual grab samples, the number of samples and tests performed increased. Grab-sample data added plant-rounds documentation which is transferred to the data historian using a hand-held device. Next, the data are sent to an Excel file where the KPI scoring system is applied. It gives the plant an indication of where it needs to go regarding water chemistry. The score sheets are archived to allow quick reference to previous scores and to identify developing trends.

Replace haz-gas detector without compartment entry

Goal was to make replacement of turbine-compartment hazardous-gas detectors safer by eliminating the need for personnel entry into the compartment to perform this task. The

best practice shared facilitates detector replacement, which is done from the roof and can be performed in a few minutes—during an overnight shutdown, for example, without impacting unit availability. Following completion of site LOTO and safety procedures, the rail that contains the bad detector can be unbolted by removing four small bolts.

Change-out of a haz-gas detector went from 24 hours to 20 minutes. Cost of the procedure dropped by several thousand dollars because scaffolding is no longer required for access. Employee safety also improved because staff is not exposed to the high compartment temperature.

Bastrop Energy Center

Protect plant personnel, visitors with machine guards

Safety best practice: Install machine guards to protect operators and others against injuries caused by exposed rotating shafts. They are your first line of defense. Bastrop Energy Center, Cedar Creek, Tex, identified a potential hazard with its diesel- and motor-driven fire pumps. Plant Manager Kelly Fleetwood reported that the shafts on both sides of the pumps were exposed, creating a potential hazard.

Plant personnel fabricated the protective covers for the exposed areas. Expanded metal guards were used to allow visual inspection of the packing follower and to monitor bearing lubrication.

Calhoun Power Co

Safety enhancements

Objective of Plant Manager Mike Carter is to reinforce the safety culture at Calhoun Power Co, a 4 × 0 dual-fuel plant in Eastaboga, Ala, by making ongoing enhancements to plant systems that protect site personnel and visitors. Two safety enhancements recently implemented are these:

    • Eliminate need for entry into a confined space to pump out the contents of a drain tank. The simple solution: Extend the tank’s drain line so staff can connect to the vacuum truck without entering the tank well.
    • Eliminate need for a ladder by installing a permanent safety platform to reach over closed-cooling-water pipes to access the generator belly-pan level switch requiring a monthly test.

Central Eléctrica Pesquería (CEP)

Benefits of lean-outage planning, execution

Following this Mexican plant’s first hot-gas-path (HGP) outage in 2018, personnel, under the direction of Plant Manager Mario Ontiveros, met to discuss the pain points identified during the work just completed. Goal was to reduce the time needed to conduct scheduled outages and to optimize resources by ensuring the integrity of people and equipment. Savings would be near immediate because there were two more gas turbines at the 7FA.05-powered 3 × 1 combined cycle in the HGP queue.

Among the many pain points identified were these:

    • Scaffolding installation.
    • Removal of blades and nozzles.
    • Lifting and dismantling of the package roof.

The methodology selected was “Lean,” which focuses on quality assurance, time reduction, resource optimization, and effective communication. The rigor applied to outage planning and execution was evident from the details provided in the best practice—including the following:

    • A visual scaffolding installation plan was implemented and strategic scaffolds were assembled prior to turbine disassembly.
    • The scaffolding plan allowed work in tandem in the disassembly of turbine elements and combustion chambers.
    • A lifting plan was implemented to disassemble the entire roof, previously removed in sections. Plus, pre-location of mechanical lifting elements for easy availability.

Results: The execution time of the second and third HGPs was reduced by 15% compared to the first outage, which lasted 19 days. Quality standards were maintained and there were no problems during and after the outages. Finally, the OEM recognized CEP’s outage team as the best in Latin America based on the results of the second and third HGPs.

Optimizing the steam-turbine cooling process

Challenge: Develop a methodology to cool the steam turbine in the shortest time possible to conduct minor maintenance while adhering to the manufacturer’s cooling curves and delivering the output required to satisfy contractual obligations. Plant had determined previously that this could be accomplished by operating one of the three gas turbines baseload at 210 MW and the other two in temperature matching for nine to 12 hours.

Plant and OEM personnel determined that, in this case, dry-air cooling was the optimal method for rapid turbine cooldown. It did not adversely impact the cyclic life of the rotor or the critical path of the outage. The method consists of injecting a regulated amount of air gradually into the HP and IP stages of the turbine while assuring that the temperature differentials between the stages were not so great as to stress the rotor. Goal: Cool the unit to the point where the turning gear could be shut down.

About 30 hours of turbine operation were gained using this procedure in place of the previous (standard) method.

Redesign of sulfuric-acid dosing system eliminates leaks

Pesqueria’s sulfuric-acid dosing system for water treatment typically experienced three or four leaks per month totaling up to about 5 liters of acid—jeopardizing the integrity of personnel and equipment. A team was formed to address the root causes of the problem and correct them.

Steps taken included the following:

    • Changed all the PVC suction and discharge hoses for the diaphragm pumps to chemically resistant PVDF pipe.
    • Upgraded pipe to Schedule 80 from Schedule 10.
    • Installed a strainer filter with blocking valves to prevent fouling of pump check valves, thereby reducing the exposure of personnel to the risk of intervention.

No acid leakage event had been identified at the time this best practice was developed, about 1500 hours after the action plan was implemented.

Effingham County Power

Maintaining fire protection during an outage

Effingham County Power’s fire protection system consists of one 2000-gpm motor-driven pump, one 2000-gpm diesel-driven pump, one 25-gpm electric jockey pump, and associated equipment and controls. The jockey pump maintains system pressure above the start setpoints for both fire pumps during no-flow conditions. Pressure switches automatically start the pumps when system pressure drops below the setpoints.

Power for the electric pumps and their associated equipment and controls is supplied from a common 480-Vac breaker housed in a switchgear with station service its only source of electricity. When the station-service transformer is taken out of service for maintenance, the two electric pumps are de-energized. Because the jockey pump is de-energized, it is unable to maintain system pressure above the starting setpoints of the fire pumps.

With the electric pump de-energized, the diesel unit will start once system pressure drops below its associated pressure-switch setpoint. When the diesel pump starts, it activates the plant-wide fire alarm; all staff and contractors must stop work and evacuate the plant when the alarm sounds.

Plant management at the 2 × 1 combined cycle in Rincon, Ga, headed by GM Bob Kulbacki, needed a way to keep the fire main pressurized when the plant was on backup power and the electric fire pumps were de-energized.

Plant personnel ran the diesel pump intermittently to maintain system pressure, to prevent erroneous fire alarms and work stoppage. This resulted in unbudgeted diesel fuel costs and excessive emissions, which could possibly lead to exceeding air-permit limits.

Staff identified the nearest motor control center supplied by a backup source of power when station service was de-energized. The closest spare breaker was about 150 ft away and required extensive trenching to run supply cables to. But a welding receptacle, which has a secondary source of power, was located only 50 ft from the fire-pump building. Staff determined that the rating of the welding supply power was sufficient to operate the jockey pump.

The plant purchased a double-throw safety switch, one plug, and the necessary cable to connect the welding receptacle to the switch located at the fire-pump building. Total cost of the materials to complete the project was $500. The two plugs were connected to the supply cable to make a jumper cable to connect the welding receptacle to the fire-pump building.

During an outage, with station-service power de-energized, the switch was permanently wired to the jockey pump’s primary power supply and one end of the temporary supply cable. Next, the temporary supply cable was connected to the welding receptacle. Then the welding receptacle was energized and staff swapped the jockey pump from normal to temporary power.

The jumper cable is stored in the fire-pump building to ensure its availability at all times. Prior to securing station-service power, the jumper cable is connected to the designated welding receptacle. When station-service power is de-energized a technician energizes the welding receptacle and swaps the safety switch from normal to temporary power, thereby providing power to the jockey pump. Fire-protection integrity is maintained in this configuration because the diesel pump will start if system pressure drops below the setpoint.

With the jockey pump in service, spurious alarms and work stoppage have been eliminated. This project has been a cost savings because outage interruptions have been reduced and the need to operate the diesel pump intermittently to maintain system pressure is no longer required.

Assuring voltage-schedule compliance

The transmission operator has provided Effingham County Power four voltage schedules which change throughout the day: 0000-0600, 0601-1800, 1801-2100, and 2101-2400. Control room operators are required to maintain the schedules within a ±2 kV band. In the past, the CRO ensured the plant was in compliance with the schedule by visually confirming the plant’s “white line voltage” and adjusting the generator’s output voltages accordingly.

To avoid operating outside the control band, a generic alarm was developed to alert operators. A narrower band was established but did not vary with the changes in the voltage schedule.

To prove to the regulatory agency that the plant was in compliance, staff developed a monthly comparison spreadsheet showing plant voltage and the allowable voltage band for each minute. This required manually inputting over 44,000 data points into the spreadsheet and reviewing to verify the information was correct.

The plant’s output voltage values were populated into the spreadsheet from the DCS historian. Obtaining the necessary data for the control bands required review the shift turnovers for the past month and manually inputting these values. Once all data were entered, the spreadsheet was reviewed for compliance and saved for future audits.

The voltage schedule is determined by Georgia System Operations Corp under NERC standard VAR-002 and issued to the plant daily. If a change is made to the voltage schedule, the alarm will not change based on the current logic. This increased the potential for human error in keeping the plant operational within the established schedules.

To alleviate this issue, staff created a series of logics and graphics in the DCS (Emerson Ovation) that would allow the operators to select which schedule is currently in effect. This input is then compared to the time of day to generate the correct alarm band for the plant. The programmed alarm will alert the CRO if the plant’s white line voltage deviates from the designated voltage schedule.

If the operator continues to operate outside of the required voltage schedule, a second alarm is

generated notifying the CRO that the plant is still operating outside of the voltage range and that it is approaching compliance limitations.

The voltage schedule, control band, and time are new logic points designated in the DCS system. All values are fed into the DCS historian for retrieval as needed to show evidence of compliance to regulatory agencies. The need for manual data input has been eliminated, reducing human-error issues and saving time during monthly reviews of VAR-002 data.

New graphics and logic have allowed both operators and management to ensure the correct voltage schedule is maintained. Additionally, the alarm points and trending capabilities have enabled staff to accurately determine if the voltage schedule is consistently maintained for reporting requirements.

The monthly spreadsheet can be updated quickly and the plan can show compliance in the time it takes to retrieve the data from the historian.

Relocating grease fittings simplifies PM

The original design of the inlet-chiller cooling-tower fan specified the location of grease fittings inside the fan enclosure, limiting accessibility to the fan bearings for maintenance. To perform bearing PM, technicians had to place a LOTO on each fan and post a confined-space permit before entering the enclosure to grease the bearings. The prerequisite steps to establish a safe work environment took approximately two hours for each fan, while greasing the bearings took only 10 minutes.

Greasing of fans typically occurred when the chiller was shut down, causing no loss of generation. But there were several instances when a fan required greasing when the chiller was online. In these cases plant output was reduced by about 2 to 3 MW.

Technicians were tasked with finding a more efficient and safe method for performing this PM.

The best option discussed was to locate the grease lines on the outside of the fan enclosure. This would eliminate the need to secure the fan and issue a confined-space permit. Staff purchased the ¼-in. stainless-steel tubing and fittings required for about $500. The remote fittings are attached to the bearings using the ¼-in. lines; flexible hose supplies grease to the fan housing platforms. A hole was made in the metal housing, and a zirc fitting mounted on the housing, to allow remote greasing.

Split bearing facilitates fan bearing replacement

One of Effingham’s chiller cooling-tower fan bearings failed, resulting in the loss of tower cooling efficiency and of plant output. Because the fans are located 42 ft above grade, and the fan assembly is about 8 ft across, replacing the bearings without use of a crane would not be safe, or technically possible. With a crane it would take two days to remove the fan, replace the bearings, and reinstall the fan—with an out-of-pocket cost of about $3200.

An easier and less expensive way to replace the bearings was needed. Staff researched alternative solutions for replacing the OEM’s single-piece bearings and opted for using slightly more expensive split bearings of the same rating, which would not require fan removal. Another benefit of the split design: Less time to replace a bearing by a factor of four—4 hours versus 16 for the original.

The initial installation of a split bearing was time-consuming, and the limited work area made it difficult. One reason: The mounting holes for the split bearings were not a direct match to those for the OEM’s bearings, so the mounting base required modification. Additional attention also was required to maintain correct shaft alignment to ensure proper fan operation.

Crews were rotated during the installation to keep everyone fresh and working safely. The new bearings were installed without incident and the plant has had no issues since the fan returned to service. Over time, as OEM bearings fail from wear and tear, they will be replaced with split bearings.

Squeezing a new air compressor into existing space without a forklift

A compressor failure left Effingham County Power with only one source of compressed air. If the remaining compressor were to fail, plant production would be lost. A rental compressor was brought in to mitigate risk. However, the rental did not have auto-start capability, so it was unclear if this unit could be brought online fast enough to prevent a loss of control air, without which the plant would be forced to shut down.

A new compressor was ordered and quotes were received to remove the old unit and install the new one. Quoted cost for removal and installation was more than $11,000. The maintenance crew was challenged to find a more cost-effective and safe method to replace the plant air compressor.

The air-compressor room configuration made it unfeasible to remove a wall, or the roof, to make the switch. The size and weight of the compressor was a consideration when planning the replacement. The limited space in the compressor room did not allow for the use of a forklift or other powered equipment. With building modifications unacceptable, team members decided to roll out the old compressor and roll in the new one using caster rollers and jacks.

The old compressor was lifted using the bottle jacks and placed on channel iron supported by the four swivel caster rollers. This allowed maneuvering the compressor in the restricted space. The old unit then was rolled out of the compressor room and the process reversed to install the new compressor. The exchange of air compressors was completed safely in about 32 man-hours at a cost of $1100.

Elwood Energy

Ensuring quality service by OEMs during gas-turbine outages

How does a powerplant manager ensure the OEM delivers quality work during turbine/generator outages? Here “quality” is defined as work safely completed with no rework required. Even with a strong contractual services agreement, an OEM’s failure to deliver the job correctly the first time can be a lose/lose situation for both the owner and OEM.

Powerplants may no longer have the talent available to adequately ensure OEMs perform their work properly. In addition, the quality of the OEM’s talent, based on Elwood Energy’s recent experience, appears to be in steady decline with crews being thoroughly fatigued towards the end of outage season.

Elwood Energy, a nine-unit simple-cycle plant, tackled this problem by contracting Viking Turbine Services to provide oversight, typically on day and night shifts, through major turbine and generator work. With major work being performed on one or more turbine/generators, Viking maintained a skilled and dedicated eye on the OEM’s performance. This freed-up Plant Manager Joseph Wood’s small staff to administer safety programs, perform other outage-related work, and respond to dispatches of other units.

The following is one example of the third-party service provider’s value: While doing routine checks, the company’s personnel noticed that two of the transition pieces completed on day shift had significant gaps between the bullhorns and bullhorn support blocks. You’re likely aware that bullhorns must be snugged down tight prior to recording set-back clearances.

Viking requested that the OEM’s contractor tighten down the bullhorns and recheck set-backs. Proper fit-up remained elusive for some of the transition pieces and the OEM decided to change all bullhorn blocks.

Over the last 10 years and numerous turbine outages, Elwood has experienced two outages requiring significant rework—both when the plant did not have third-party support. Numerous other outages have been performed with oversight that have not required rework. During these outages, Viking routinely identified issues during routine observations and during agreed-to quality hold points.

Essential Power Newington

Rehabilitation of EHC fluid boosts starting reliability

During a routine plant cycle/startup, the right-side HP steam control valve failed to open and allow steam to flow to Essential Power Newington’s D11 turbine. The startup was aborted, the electrohydraulic (EHC) control system was secured by LOTO, and the servo valve controlling fluid flow to the valve actuator was replaced. Newington was restarted and the HP control valve responded as expected; plant operation was restored to “normal.”

When the failed servo was shipped to Moog for rebuild, an in-depth failure analysis found what appeared to be a varnish-like substance on the nozzle top and flapper to the torque motor. An EHC oil sample was sent to a certified laboratory for contaminant (varnish, water, metals) analysis, an estimate of the oil’s remaining service life, etc.

Lab results: The deposits, originally thought to be varnish, actually were carbon. At the time of the servo failure, the EHC system included a kidney-loop varnish removal/filtration system. Site personnel, who relied on the fluid OEM for sample analysis (no charge), came to learn that the lab effort did not fully check the fluid for all required parameters. The only parameter that had dropped recently was resistivity and the reason for that was to be investigated.

Staff’s first thought was to dump the oil and flush the system, which would have been extremely expensive.

Plant personnel, led by Plant Manager Tom Fallon, embarked on a multi-faceted plan to review contaminated-oil sample results, discuss possible solutions with industry experts, implement corrective actions to mitigate system condition, and avoid a fluid change-out.

Newington staff worked with Advanced Fluid Systems, a fluid-power solutions provider, and filter OEM Hy-Pro Filtration to develop the following approach for removing contaminants from the system:

    • Change the EHC fluid filter media to eliminate sparking.
    • Inject dry instrument air into the head space of the tank.
    • Rent an electrostatic contamination removal skid to pull out the carbon deposits.
    • Use improved oil analysis to monitor trends.

Also, a hydraulic fluid pump rep visited Newington to perform a system walkdown and make sure there wasn’t some abnormality causing the fluid contamination.

Following the EHC system changes, staff performed semi-monthly sample analyses to monitor trends in fluid cleanliness. With the results of the analyses showing improved fluid characteristics over time and the visual indication of the fluid becoming more transparent, staff knew the plant’s approach was working.

By discussing Newington’s problem with many industry experts, staff was able to get several opinions on what to look for regarding the source of contamination, which ultimately was carbon buildup. With expert input and the plant’s commitment to finding a solution, staff was able to effectively clean-up the system and eliminate the need to replace the existing fluid.

Lesson learned: By focusing on an issue and not letting the path of least resistance become your answer, you can effectively eliminate a problem long-term. Had staff simply changed the fluid without performing the other steps in the process, carbon contamination would have reappeared in a matter of time.

PI tools help improve situational awareness, work processes

This best practice is divided into two different, but similar, business-challenge paths and targeted solutions surrounding the use of existing PI tools and control-room recordkeeping. Both PI tools described below have proven extremely successful at Newington. Each has its unique success stories, but both ultimately provide excellent efficiency and awareness improvements to the site. Improving facility situational awareness and focus while reducing the many inherent distractions, and otherwise manual processes, is always a benefit.

No. 1. Situational awareness and information-sharing is a best practice that should be used across multiple fronts. With regard to operational awareness and NERC compliance, Newington decided to further utilize the PI Notification Tool to automatically send e-mails to communicate several different key plant operational and NERC compliance conditions. PI Notifications included chemical-tank levels, breaker operational counters, key equipment temperature monitoring, facility forced power oscillations, and NERC VAR-002 notifications.

Situational awareness for facility personnel is crucial to ensure timely and accurate response to changes in plant conditions. Understanding trends and future consequences are easily tracked using PI Notification tools at the facility level. These notifications are used for real-time monitoring, e-mail alerts, compliance requirements, and chemical-inventory reorder processing.

Newington personnel now are better tuned-in to operational and equipment status—including feed-pump bearing trends, voltage schedule, and Automatic Voltage Regulation (AVR)/Power System Stabilizer (PSS) status as required by VAR-002 requirements, chemical inventories for automatic notifications to chemical suppliers, breaker motor and cycle counters for equipment monitoring and forced megawatt oscillations. This allows multiple key personnel to be aware of conditions in the facility and increases the efficiency of many otherwise manual tasks.

Staff created all PI Notifications based upon input from the operations manager on needed awareness tools. Several different notification categories were created, as noted above. Notification and alert levels were set up to track initial concerns and then, if necessary, any communication requirements based upon the condition.

Currently, 10 notification elements are used by PI. Some look at real-time statistics, others at trends and future objectives necessary for compliance and equipment protection. To date, several notification e-mails have been used. They provide excellent awareness to plant conditions. Daily automated e-mails to the facility’s boiler chemical provider from PI allow for automatic reorder tracking and awareness, eliminating the need for phone calls or e-mails to order chemicals

No. 2. CRO distractions are numerous and having the ability to reduce them is always a challenge. During the course of any major operational evolution—such as plant startup or shutdown—the ability to focus on the task at hand is extremely important. One of the requirements in any control room is log-keeping. For several years, the facility has used an electronic program called eLogger for this purpose, but entries in the database still required manual input.

In an effort to further reduce operator distractions, a new eLogger log-entry automation tool was developed, tested, and implemented by staff. The PI database was interfaced to the e-Logger application, providing PI-generated log entries for key plant and equipment status changes, greatly reducing the amount of manual log entry required by employees.

Automating logging events is an extremely effective solution for removing distractions, yet still accomplish the record keeping needs of the facility. Automatic logging was setup for conditions such as blower or pump starts/stops, turbine starts/stops, etc.

Using PI to communicate automatically with the eLogger database allows for a reduction in the hundreds of otherwise distracting manual logging tasks required by the operations staff. This drives better focus on the control system for operations to perform critical tasks while still completing certain required log-keeping “behind the scenes.”

A plant employee designed and constructed the application necessary to allow the PI and eLogger databases to communicate continuously. The application monitors numerous PI tags for state changes then passes the event to eLogger, where a log entry is automatically generated.

There are currently over 60 different PI tags communicating with eLogger and recording as necessary. This list will be expanded continually based on need and efficiencies following input from others. Improved focus and attention on the control boards has been accomplished with reduced manual logging needs.

Hunterstown Generating Station

Attention to leaking valves slashes water use

Goal to reduce cycle steam and water losses focused on identifying leaking valves and making repairs. A vendor was contracted to perform valve leak surveys beginning in late 2016. From 2017 to 2019, many valves were tested and numerous large-to-medium leaks were documented. Valve repairs and replacements implemented during outages were highly successful. Cost of demin water production dropped by $100,000 over two years while capacity factor increased by 8.3% during the same period.

NDT program eliminates forced outages caused by steam-drain failures

In 2016 and 2017, Hunterstown, a 3 × 1 combined cycle under the direction of Plant Manager Tom Hart, experienced eight unplanned outages to repair drain-line leaks caused by steam erosion. These outages represented 18 days of unavailability in the two-year period. The leaks occurred most often during startup and shutdown operations and presented potential hazardous situations to personnel because of their locations.

The plan developed to eliminate these forced outages included the following actions:

    • Review work-order and weld-log histories to identify the most frequent recurring failure locations—HP and IP continuous blowdown drain lines. These lines are characterized by large differential pressure gradients and two-phase flows which accelerate pipe-wall erosion rates.
    • Create prioritized inspection plans for HP and IP continuous-blowdown drain elbows. Include drain-line isometric drawings showing elbow IDs based on upstream MOV tags. Elbow IDs were sequentially numbered in the direction of steam flow to more easily track x-ray inspection images and reports, and to build a tracking spreadsheet for repairs.
    • Radiograph small-bore drain elbows during normal plant operation without removing insulation or lagging, using large receptor panels to capture the entire elbow and part of the downstream piping in single-exposure shots.

Inspection and repairs eliminated unplanned outages attributed to HP and IP steam-drain-line fitting failures. A rope alternative to scaffolding for access to failure locations saved tens of thousands of dollars. The bottom line: There was no spending for scaffolding and insulation removal.

Maximize GT generation with evap coolers in service

Maximize use of gas-turbine evaporative coolers by implementing control logic improvements to automate starting and stopping of the evap coolers based on the following: ambient and inlet air temperatures, IGV angle, inlet bleed heat (on or off), and evap sump level. The cost of implementation was about $16,000 for a first-year gross-margin increase of approximately $25,000.

Benefits of transitioning from CO2 bottles to bulk storage

When generator purges were needed, Hunterstown relied on portable 160-liter CO2 bottles. Pressure in the bottles decreased over time (outdoor storage, exposed to sunlight), rendering the bottles minimally effective. Multiple bottles were needed to complete a single purge.

Plus, time-consuming operator manipulation of the bottles was needed to complete each purge. Staff had to transition between units and the CO2 storage facility and to secure spent bottles and line up new ones. Such maneuvering was critical during emergency generator purge situations because of the time required to begin flowing CO2 to a generator. On more than one occasion, nearly 30 minutes elapsed between the time a purge was started and gas began to flow.

Solution was simple: Install a bulk storage system with a capacity of 1550 gal having these features:

    • Electric vaporizer to convert liquid CO2 to vapor to prevent two-phase purge flow.
    • CO2 condenser to convert excess vapor back to liquid, thereby preventing tank losses to atmosphere.
    • Safety shutoff device to ensure liquid CO2 cannot reach the generators.
    • Instrumentation for tank level and pressure with data routed to the DCS to monitor consumption rate and to reorder CO2 when necessary.

Cost of the system, installed in February 2020, was less than $350,000—including equipment, engineering, installation, and commissioning. Bulk storage eliminates bottle demurrage charges of about $11,000 annually and simplifies operator actions to start CO2 flow, saving several minutes over the bottle alternative.

Expectation is that the four units on site can be purged twice before a refill is needed, while retaining sufficient gas for two more unit purges (total of 10).

Marcus Hook Energy Center

Upgraded stack for cooling-tower fans facilitates maintenance

Marcus Hook Energy Center, a 3 × 1 combined cycle under the direction of Plant Manager Frank Meade, has a 12-cell mechanical-draft counterflow cooling tower with multi-speed fans. Blade-tip-to-stack contact was causing wear on both components. The original stacks were made of molded fiberglass, with only vertical ribbing. They were constructed in sections, through-bolted together on the inside. If hardware loosened while in operation, a confined-space entry and extensive scaffolding would be required to replace or tighten.

The new stacks have ribbing in both the vertical and horizontal directions, making this design less susceptible to flexing and reducing the probability of blade-tip-to-stack contact. This also lessens the chance of hardware coming loose. The new stacks connect sections with a completely exterior face-to-face flange, allowing the tightening of all hardware from the outside—thereby contributing to safer, less-expensive, and more-effective routine maintenance.

The increased fan-stack rigidity allows use of gear reducers with standard output shafts—typically more readily available and less costly than the original gear reducers. This allows fan blades to be located lower in the stack—hence closer to the sidewall—increasing cooling efficiency by decreasing tip vortex. The plant has replaced several of the OEM stacks with the improved design and will continue to do so over the next few years until all cells are retrofitted with the new stacks.

MEAG Wansley Unit 9

Bearing-tunnel fire alarms enhance personnel protection

Plant Manager Timothy Williams, MEAG Unit 9, Franklin, Ga, wanted to assure a high level of safety for personnel working inside the gas-turbine exhaust enclosure. NFPA-12 provides guidance for carbon-dioxide extinguishing systems typically specified for generating plants powered by gas turbines. The standard provides the minimum requirements for a system designed to flood the compartment with CO2, which does not support combustion or life, should a fire be detected.

There is the potential that an individual could be working inside the enclosure, unaware of a fire event, and could be a long distance from the nearest exit. Example: What if the CO2 vented out of the adjacent lube-oil drains and into the exhaust enclosure?

At MEAG Unit 9, as in most plants, mandatory signage is in place as a warning, but is that sufficient? Staff decided an additional measure of protection was required since there were areas where CO2 could be present, but no visual or audible alarms were available. So, they installed additional three-horn-and-strobe-light combination alarms at the following locations:

    • Near the bearing-compartment vent.
    • At the entrance door to the exhaust section.
    • Inside the exhaust-section enclosure.

This now provides personnel working inside exhaust enclosure immediate and effective notification of the danger in the unlikely event a fire were to occur in the compartment.

Plant Rowan

Training videos promote shop safety

Following an extensive maintenance-shop overhaul and retooling at Plant Rowan, Salisbury, NC, staff was challenged by Plant Manager Chris Lane, supervisors, and the site safety council thusly: How do we ensure everyone operates and maintains the equipment according to our company safety policy, common industry practices, and manufacturer equipment procedures?

Plant operators may only use a certain piece of equipment infrequently—such as during outages. The lack of daily use concerned staff because proficiency conceivably could be lost during periods of low maintenance.

The management team, together with the site safety council, provided direction for the creation and implementation of a series of Just-in-Time (JIT) “refresher” videos. A primary goal of the effort was to keep the videos short, each averaging only about five to six minutes per piece of equipment, but including as much information as possible.

The belief was that in this amount of time an experienced operator could demonstrate safe and effective operation or maintenance of a given piece of shop equipment with adherence to all company safety policy and equipment procedures. Equipment covered included pedestal bench grinders, horizontal band saw, drill press, various machining coolant systems, etc.

No narration was used; narrating the videos was deemed time-prohibitive at Plant Rowan. Instead, video editing software was used to add detailed on-screen “pop-ups” during final editing. This included pertinent information and hazards at each step of the equipment’s operation. Examples: When PPE is required and what type; tips for safe operation; hazards and examples of improper operational practices, etc.

Once completed, the videos were loaded on a 40-in. wall-mounted LCD monitor located in the maintenance shop for anyone to access prior to equipment use and as part of their pre-work job safety analysis.

The videos have been credited with contributing to significantly fewer occurrences of improper tool/equipment use—such as non-ferrous metal fouling on bench-grinder wheels, prematurely worn metal band-saw blades, and less wear and tear on equipment. Plus, there have been no safety issues.

Rathdrum Power LLC

Catwalk around clarifier promotes safe maintenance

Rathdrum Power, a 1 × 1 combined cycle located in Rathdrum, Idaho, managed by Richard Ihrig, is permitted as a zero-discharge (ZD) facility. As such, the plant does not discharge any process water. Undesirable solids are removed from the various process-water streams by mechanical means in the ZD area of the plant.

An issue with the plant’s ZD system was the design of its ageing clarifier. Sodium carbonate (soda ash) carries over and plugs discharge holes around the clarifier’s weir. Occasionally plant personnel have to clean the weir and service the sulfuric-acid discharge piping, tasks requiring use of an extension ladder. Putting up a ladder and climbing to the top of the clarifier to tie off the ladder posed safety concerns and was not viewed as efficient use of employee time.

With help from a local engineering firm, staff decided to resolve the problem this way: Build a catwalk around the outside of the clarifier so O&M personnel could access all areas at the top of the vessel. It was designed with a grating of Type-304 stainless steel and handrails and supports of carbon steel.

The catwalk enables access to the clarifier weir and sulfuric system without need for an extension ladder requiring fall protection. With easier access, cleaning intervals have been reduced. Plus, fewer personnel are required to do the work.

Woodbridge Energy Center

Rearrange collector air intake for better performance

The D11-A steam turbine at Woodbridge Energy Center, Keasbey, NJ, managed by Chip Bergeron, is located about 40 ft above the condenser and associated balance-of-plant equipment and runs primarily baseload. The collector air intake filters for this unit were not safely accessible without locking out the exciter, regardless of whether the unit was online or offline.

Reason: The busbar location where the power cables to the brush rigging are bolted is directly above the intake filters. After a steam-turbine trip, caused by a collector ground fault during a heavy rain event, the collector’s filters were removed and found caked in carbon dust. Plus, the collector was damp from the rain being pulled through the door seals by the vacuum created by the clogged filters.

The week prior, an online ring grind had been performed which normally would not be a contributing factor except that the dust generated during the grind was being exhausted and then partially re-ingested by the collector filters. Plus, the filters, which are impossible to inspect or service with the plant online, also are subjected to an excessive amount of carbon dust from normal brush wear, because of the recirculation effect. These two issues eventually caused the aforementioned unit trip and maintenance headache.

The problem was resolved by redesigning the air intake assembly and bringing the ductwork down to ground and installing new, easily accessible filters that could be inspected and serviced with the unit in operation. Additionally, the exhaust duct was reconfigured to direct any carbon dust well beyond the new air intake.

With the filters relocated, the overall cleanliness level of the collector housing improved dramatically and water ingestion is no longer an issue. The air intake filters have been removed, inspected, and cleaned several times with the unit online, without any issue. Addition of a differential-pressure gage across the filters has further improved maintenance efficiency by giving the site team a real-time view of filter health.

Doubling down on haz-gas analyzer reliability

At Woodbridge Energy Center, major equipment is located almost entirely outdoors. When the site went commercial in 2016, it was one of the first to use a newly designed aspirated hazardous-gas detection system, which relies on instrument air and an aspirator to pull air samples from two different compartments on each gas turbine through dedicated LEL sensors.

These sensors have the capability to shut down the turbine should two in either compartment go into a state-of-alarm—that is, high LEL readings and/or a loss of sample flow through the LEL detector—at any given time.

Because the detection system is exposed to the elements, issues immediately began to arise with sensor stability on days when ambient conditions changed quickly. The issue was exacerbated when high winds were present. Sensor instability caused numerous false alarms which led to unit runbacks and in a few instances, trips.

Staff learned through testing that the factory-installed stainless-steel cover for the LEL sensors was creating a thermal-sensitivity issue within the sensor itself. This was most evident during sudden rain events in the summer where the cover and sensor temperatures could drop by 20 deg F in a matter of seconds. That temperature drop was even greater (perhaps even 100 deg F) when the rain event occurred right after the sensor cover had been exposed to direct sunlight. Winter brought similar issues where the sunlight would warm the sensor but then high winds would cool it off rapidly and repeatedly.

To solve the problem, the steel cover required protection against the elements. Plant staff and the OEM decided the best option was to double up on the sensor covers. The factory-installed steel cover would stay as is, but a new plastic shield would be clamped around it. Plastic conducts heat very poorly and also blocks most, if not all, the rain and wind from reaching the steel cover.

Since installing the secondary covers, performance of the 24 haz-gas detectors during weather events has been flawless. This simple and relatively inexpensive solution dramatically increased plant reliability.

Color-code plant drains to expedite event response

Woodbridge Energy Center is boarded on two sides by wetlands. The site must properly capture and direct water from different sources—such as blowdown tanks, chemical containments, and various drain sumps. In order to perform this task, Woodbridge uses 128 floor drains and five sumps to direct water to two separate locations (cooling-tower reuse or the local sewer authority).

Additionally, storm-water runoff is captured by large drains which empty to storm-water basins. Those basins then drain into a retention pond which discharges to the adjacent wetlands.

At face value, this is a typical configuration for outdoor powerplants; but Woodbridge was faced with a problem when it came down to how to properly react to an accidental release (chemical, oil, etc). Because the floor drains were not labeled, it would not be readily apparent (in the moment) what sump should be shut down to prevent the product from escaping to the larger systems and potentially the environment.

This was a significant concern because the sumps, which can only be shut down manually, could easily be several hundred feet away and/or obscured by a building or piece of equipment. Shutting down all sumps would be impractical and time-consuming. The site team had to develop a way to easily and rapidly identify what sump to shut down should a release event occur.

To expedite the drain/sump identification process, plant personnel developed a color-coded chart, which was broken down by sump. The color codes were then used to create permanent signs for each sump, calling out its name and discharge location. After the signs were in place, an identifying color-matched circle was painted next to each drain. The color corresponds to the sump which the drain goes to. Now, if an accidental release occurs, the plant team will instantly know which sump to secure, saving precious time.

Progress in driving towards cultural excellence

As Woodbridge Energy Center entered its fourth year of commercial operation, management wanted to focus on understanding how to reinforce the best elements of the plant’s culture. The challenge the team faced was how to effectively gather and present information in a way that provided understanding and visibility of individual program elements and how they connect the team as a whole.

In November 2018, plant personnel were surveyed and asked to list their top five personal values and rank them in order of importance to themselves. The survey was anonymous to ensure that employees felt comfortable enough to put down their true top five. Once all of the results were collected, the responses were compiled, combined, and sorted in order to come up with the top five guiding values for the entire team.

For Woodbridge, those top five values were teamwork, accountability, integrity, learning, and respect. Results in hand, the team, at a December 2018 safety meeting, came up with the three areas they felt would most benefit from knowing team values—safety, excellence, and availability. These were promoted on the graphic, which then was posted in various locations around the site (conference room, control room, etc) as a reminder of what the team uses to guide and drive daily decision-making.

During the six safety meetings in 2019, each of the five values was singled out and discussed in detail. The discussions focused on explaining what each value truly means to plant personnel, how it applies to the work at hand, and in most cases, a group activity or survey in order to continue building a positive work climate. Surprisingly, the deep dives on team values proved the most beneficial and rewarding part of the process.

This was particularly evident during the February 2019 meeting where the value of learning was highlighted. Prior to the meeting, plant personnel were given a 70-question Learning Styles Survey and asked to answer each question from 0 (not like me) to 2 (exactly like me). Survey results were averaged across all 22 team members to create a radar plot showing how the team learns best. Using this information, management was able to cater to the remaining values discussions in a way that would be the most beneficial to employees.

The learning-styles assessment allowed development of a teamwork exercise that encompassed the styles of all members. These learning styles were taken into consideration when creating future training programs for the full plant staff. This personalized approach to the values discussions, safety meetings, and training in general continued on through the remainder of 2019. It culminated in a year-end values survey to reflect on how this experience improved staff morale while creating a sense of ownership.

After the values assessment on learning styles, it was possible to plan training for the remainder of the year that best met the needs of the plant staff. This intentional planning led to more successful training and higher concept retention.

 

Lesson learned: Heat tracing demands constant attention

By Team-CCJ | March 14, 2022 | 0 Comments

A roundtable on winterization at the 2021 conference of the Combined Cycle Users Group drew on the vast experience owner/operators who have faced heat-trace-system challenges at their facilities. There are still two outage seasons before winter 2023 to implement the many best practices shared by colleagues from Woodbridge Energy Center, Dogwood Energy, and others.

By virtue of its location and importance to the grid, Woodbridge, a 2 × 1 7FA.05-powered combined cycle located outdoors in the Northeast, has heat-trace experience beyond that of many others in the industry. Engineering Manager Mike Armstrong represented his plant in the roundtable.

What follows are details on Woodbridge’s heat-trace initiatives, some of which were not discussed during the roundtable because of time constraints.

Get off on the right foot. Plant personnel learned during commissioning, and afterwards, that poor installation practices coupled with the lack of documentation made it difficult to troubleshoot the heat-trace system. This required staff to spend roughly 60 man-hours per week identifying and fixing issues with heat-trace circuits not functioning as designed. The poor performance of the heat-trace system jeopardized reliability and operability by allowing critical instruments and equipment to freeze-up.

Woodbridge was constructed by a single EPC contractor with multiple equipment suppliers. Design of the heat-trace system was subcontracted to a reputable supplier while installation was handled by the EPC contractor’s craft electricians, who had little or no experience with heat-trace equipment.

The various scope-of-supply boundaries and types of heat tracing proved problematic. Many field changes were required to complete the installation—changes performed without the knowledge of the designer and poorly documented.

Heat tracing was designed to maintain an equipment temperature of 40F at an ambient of -8F. The heat-trace supplier implemented the use of microprocessor-based temperature control and monitoring panels which required other new equipment—including various temperature sensors, new alarm capability, DCS integration, self-testing circuit cards, and programmable RTD outputs.

The lack of qualified oversite from the heat-trace designer during equipment installation and in preparing documentation of as-built conditions proved challenging for the plant operator once it took possession of the facility.

The first step in fixing the problem was to bring back the original heat-trace designer to audit the entire system and identify and correct any deficiencies. This required all 612 individual circuits to be reviewed to ensure the correct materials were used along with the correct installation practices. Next, all the documentation was updated to reflect as-built conditions. This information and a thorough review ensured the system was designed and installed as originally intended.

With the proper installation and operational techniques identified for the new technology, the plant operator developed a heat-trace guide to provide a laymen’s approach to better understanding of equipment and operational requirements. In the guide, details which had been segregated because of scope breaks are included in one location, eliminating the need for multiple sources of documentation. The guide is written in plain language and includes pictures of installed equipment to better acclimate the reader and facilitate troubleshooting.

Success. Using the original design team to identify and fix the installation issues the heat-trace system achieved its specified objectives. System performance now is aligned with the original design intent, ensuring safe and reliable operation of plant equipment during times of inclement weather.

Upon release of the guide, personnel were immediately able to reference site-specific information for heat-trace issues in a timely manner. Today, only about 10 man-hours per week are required to properly troubleshoot system issues, down from the 60 mentioned earlier. The guide also helped personnel identify equipment improperly installed, before it adversely impacted heat-trace performance.

More ideas. One or more of the following best practices pertaining to the development/design, and construction/startup of a plant-wide heat-trace system also may have value at your facility:

Development/design.

    • Add smart-panel amp indication on each circuit as well as a light to visually indicate that the circuit is energized. This makes it easier for operators to walk down the system, verifying that the heat tracing is on and working when it should be.
    • Have your engineer do a detailed evaluation of all vendor equipment (gas and steam turbines, HRSGs, etc) requiring heat tracing and make sure that the information is clearly presented to the heat-trace system supplier.
    • The mechanical engineer responsible for the heat-trace design scope should be the same person who reviews the vendor’s design isometrics. The field engineer may not necessarily understand the mechanical properties of the piping system and may miss things that should be included in the isometric drawings. In addition, the mechanical engineer is better positioned to be aware of potential piping changes needed.
    • Since the heat-trace design usually is not complete until late in the project, the necessary conduit cannot be installed until very late in the schedule. You can benefit by moving a large portion of this work forward. For example, run small (12 in.) cable trays in areas known to require heat tracing (finger racks, main racks, bottom of HRSG, etc); once the heat-trace design is finalized and power connection devices are located, only short pieces of conduit from the tray to the devices are needed.

Construction/startup.

    • Ensure that compressor bleed-valve actuators and inlet-filter differential-pressure instruments are heat-traced and insulated properly for adequate freeze protection.
    • Coordinate with the instrumentation fitters to make sure that when cutting back the heated tube bundles they leave at least 3 ft of heat-trace cable on both ends. When they cut the heated tube bundles short, there is not always enough cable to reach the power connection kit inside the heated enclosure, or to trace the root valve. This results in having to relocate power-connection kits and add jumpers to accommodate.
    • Ideally, start the heat-trace crew when the piping discipline is at least 65% complete. Prior to this, the pipe systems generally are not complete (missing valves, permanent supports not installed, etc) which creates rework for heat-trace crews. This will allow a large runway ahead of the heat-trace crew, increasing productivity. Impact upon the project completion schedule and weather conditions may override this.
    • When installing the rubber boots in the termination kits, the leads tend to bunch up at the bottom and touch. If there’s a ground fault during commissioning, 80% of the time it’s likely to be in the rubber-boot connection.
    • Perform a thorough heat-trace audit each summer to identify and address any issues before the cold weather sets in.

Learn from one utility’s arc-flash safety program

By Team-CCJ | March 14, 2022 | 0 Comments

A quick search of the CCJ’s editorial archives shows how much arc-flash safety is on the minds of owner/operators, especially in the best practices category. Whether you have a formal arc-flash safety program or not at your facility, there’s still much to be gained by listening to Aaron Neuvert’s presentation on this important topic at the Combined Cycle Users Group’s 2021 virtual conference, available on the Power Users website.

His company has incorporated the relevant OSHA, National Fire Protection Association (NFPA), IEEE, and state standards to create its own program which “summarizes and simplifies [these standards] for practical application.” The presenter’s commentary substantially expands on the content of the slides.

Arc flashes are low-frequency, high-impact events but their occurrence is increasing industry-wide. About 2.5% of arc-flash incidents result in the death of a worker; 95% are caused by human error, so training and strictly adhering to, and updating, best practices are critical. Clear and proper labeling is vital, as is the use of the proper personnel protective equipment (PPE), both areas of the standards which have been updated recently.

A few main points:

    • An open-air arc in a switchyard or a powerline may be more dramatic, but arch flashes in a contained space (arc in a box) are much more dangerous because the energy has only one path—towards the opening.
    • Stay away from ground cables and ask the question, “Can a ground cable withstand the faults the manufacturer claims it can?”
    • New best practices are coming into play, based on recalculation of so-called minimum approach distances (MAD).
    • When modeling for boundary protection, test for equipment voltage, rather than rely on rated design data from the supplier.
    • The arc-flash boundary becomes effective only when hazardous tasks (table) are being performed on or around the equipment.
    • Always wear flame-resistant clothing when working around equipment prone to arc flash.

An audience member asked for thoughts on arc flash for dc equipment. The speaker responded that they are only starting to test dc systems; not enough is known about them yet, but he expects updates to industry practices within the next five years.

Long term, Neuvert projected, the solution is to become a “remote-racking” organization and use robotic devices which “take the employee out of the hazardous area.”

Tasks for which the arc-flash boundary becomes engaged

    • Any activity that increases the chance of a fault condition.
    • Anytime the MAD is breached by a body part or uninsulated tool.
    • Working on energized electrical conductors and circuit parts.
    • Performing voltage testing.
    • Racking potential transformer (PT) trays.
    • Installing or removing protective grounds.
    • Racking breakers into or out of energized compartments while within the arc-flash boundary.
    • Installing or removing temporary barriers that are in direct contact with exposed live parts.
    • Installing or removing bolted covers near exposed energized parts.
    • Installing or removing buckets from energized motor control centers that are not equipped with integrated arc-flash safety features.
    • Manually operating breakers, switches, or disconnects.
    • Opening hinged covers on cabinets or panels that contain exposed energized parts.
    • Installing or removing fuses.
    • Working on control circuits with exposed energized electrical conductors and circuit parts greater than 120 V.
    • Opening voltage transformer or control power-transformer compartments.

KinetiClean presents new option for HRSG tube cleaning

By Team-CCJ | March 14, 2022 | 0 Comments

Calling it “safer, faster, and deeper” than dry-ice blasting, Jeff Bause, CEO, Groome Industrial Service Group, introduced participants in the 2021 virtual conference of the Combined Cycle Users Group to KinetiClean HRSG tube cleaning, a patented kinetic shockwave technique widely used in other industries but new to combined cycles. It was developed by Explosive Professionals Inc. (ExPro), a detonation-based cleaning services firm with decades of industry experience.

Only a few weeks after his CCUG presentation, Bause announced that Groome had acquired ExPro, uniting the latter’s patented processes and Groome’s 50-plus-year history in providing premium powerplant services—many identified with the hot-gas path in gas-turbine-powered simple- and combined-cycle plants. ExPro executives Brad McGinnis (President/CEO) and Rod Hall (Executive VP) have transitioned to the Groome team, bringing the skills and expertise honed at the 26-yr-old company to increase the number of critical service options available to owner/operators.

One of the stated competitive advantages of KinetiClean over alternative tube-cleaning techniques is that some of the work involved—such as the placement of detonation (a/k/a det) cord—can be performed while other outage work proceeds in parallel. Additionally, limited to no scaffolding is required for this process.

KinetiClean is a three-step process. First, the shock waves created by the det cord curtain dislodges deposits from the HRSG’s finned tubes, then compressed air removes any loosened deposits that remain, and finally, the floor of the HRSG is vacuumed clean.

The process begins with the installation of det cord, described as a flexible textile jacket encasing PETN which is an extremely stable powder plastic explosive. Simply, a curtain of det cord, spaced 12 to 18 in. apart between tube bundles, extends the length of the finned tubes to be cleaned (photo montage). Det-cord acing is based on the nature and volume of foulant as determined by ExPro. The det cord curtain is only armed when the blasting caps are introduced.

When the cord detonates along its length at a velocity of about 23,000 ft/sec (optimal for hard deposits), the ensuing shock waves remove debris from tube surfaces and fins. Importantly, no detonation material or tools touch any HRSG internal surfaces.

Next, patented air vestibule machines remove loosened debris that settled on fins below with high volume/high pressure air. The machine is digitally programmable to ensure full tube-bundle coverage. Once all debris has been removed from the fins, vac trucks are utilized to collect the material from the HRSG floor. The primary focus of this turnkey operation is to mitigate the chance of any opacity issues upon startup. A typical job takes six to eight 12-hr shifts to complete, meaning the cleaning of an F-class HRSG is a three- or four-day project.

Knowing that the mention of explosives was likely to send palpitations to the collective heart of the audience, Bause included as one of his first slides a record of the industry’s safety and training record—specifically, no reportable incidences, lost time, or fatalities over the last three years, each representing close to 30,000 hours of work. A crew of seven typically does the work, including one licensed blaster.

Bause gave several case studies to wrap up, each exhibiting four to six tons of material removed and a 4- to 5-in.-H2O differential-pressure improvement. During one site’s work, damper repair work was conducted in parallel. Other slides quantify the general benefits of tube cleaning, although few combined-cycle personnel need any convincing on that front.

During the Q&A, attendees learned that 30 minutes following detonation, workers can enter the HRSG; noise levels are not expected to impact neighbors; that the technique is effective at removing ammonium bisulfate deposits; and the technique is not recommended for catalyst cleaning, although the patented air vestibule machine could be adapted for non-scaffold cleaning of the SCR catalyst at some point in the future.

7F Users Group to meet May 23-27 in Dallas, REGISTER TODAY!

By Team-CCJ | March 10, 2022 | 0 Comments

The world’s largest user organization supporting owner/operators of 7F gas turbines promises the industry’s most robust in-person meeting of its type since the pandemic began two years ago, when the group meets at the Fairmont Dallas Hotel, May 23-27. Recall that the 7F Users Group pioneered a return to in-person conferencing last August, conducting its 30th anniversary meeting in St. Louis.

This year’s vibrant, reconfigured program promises a not-to-be-missed event. Vendor solutions highlight the mornings both Monday, May 23, and Tuesday, May 24, with traditional general sessions in the afternoons, and vendor fairs from 4 to 7 p.m. Wednesday is dedicated to general sessions. Thursday is GE Day. Friday morning is reserved for the OEM’s deep-dive knowledge-sharing program and hands-on live outage hosted by FieldCore.

It’s important to register soon to get the $445 early-bird conference fee, which increases April 23, and to assure your accommodations are at the heavily discounted $185 daily group rate (plus tax, of course), which ends May 2. An online reservation link will be provided to attendees after they register. You cannot arrange for a room at the conference rate any other way.

Stay tuned to www.powerusers.org for program updates as they become available and other announcements.

More detail: The vendor solutions presentations are arranged both days in four 30-minute sessions with four or five services providers presenting simultaneously in each session. Five platinum-sponsor presentations, aggregated in a fifth 60-minute session, conclude the morning programs.

Monday, attendees can listen to half-hour presentations by AGT Services, Certrec, Flow-Tech Industrial, HRST, PSM, APG, CTTS, Cutsforth, Emerson, Independent Turbine Consulting, Core Tech, Oilkleen, Thomassen Amcot, EthosEnergy, NEC, RelaDyne, and Tetra Engineering; plus, hour presentations by Arnold Group, Gas Path Solutions, MD&A, Shell, and TC&E.

Tuesday’s half-hour presentations are by Camfil, HRST, Integrity Power Solutions, MD&A, EagleBurgmann, JASC, Kinectrics AES, Koenig Engineering, Moog, Lectrodryer, NEC, Riverhawk, and Sulzer; plus, hour presentations by AGT Services, Doosan Turbomachinery Services, ExxonMobil, IAFD, and PSM.

Access the agenda summary to plan your participation before arriving in Dallas.

The general sessions include a lineup of presentations and discussions by and among users on safety, combustion, auxiliaries, rotors, exhaust systems and components, and other topics yet to be finalized.

GE Day topics include safety; 7F fleet trends; outage planning and execution; GT systems reliability, controls basics, architecture, troubleshooting, and solutions; compressor/turbine/rotor; generator and electrical systems; parts and repairs; and combustion.

Vendor fairs will showcase the products and services from five- to six-dozen companies each night. The generous three-hour exhibit hall program allows you to visit all the companies on your punch list while taking advantage of the heavy hors d’oeuvres and open bar.

2022 7FUG Exhibiting Companies

3angles, Inc.
Advanced Turbine Support
AGT Services, Inc.
Allied Power Group
Alta Solutions, Inc.
American Thermal Solutions
AMETEK Power Instruments
AP4 Group
Arnold Group
AZZ, Inc. – The Calvert Company
Badger Industries
Bearings Plus
Braden Filtration, LLC
C.C.JENSEN, Oil Maintenance
Camfil Power Systems
Certrec Corporation
Chanute Manufacturing
Chevron
Conax Technologies
Conval
Core Tech and CTTS
CUST-O-FAB
Cutsforth, Inc
Dekomte de Temple LLC
Donaldson Company
Doosan Turbomachinery Services Inc.
Durr Universal, Inc.
EagleBurgmann Industries, LP
Emerson
Engineered Pump Services
Environment One Corporation
EthosEnergy
ExxonMobil
Falcon Crest Aviation Supply / Zokman Products
Filter-Doc Corporation
Flow-Tech Industrial
Frenzelit, Inc.
Freudenberg Filtration Technologies
Gas Path Solutions
GAS TURBINE PARTS & SERVICES, INC.
Groome Industrial Service Group, LLC
GTC Control Solutions, Inc.
HILCO Filtration
HPC Technical Services
HRST, Inc.
Hy-Pro Filtration
Hydralube
HYTORC
IC Spares
Independent Turbine Consulting, LLC
Industrial Air Flow Dynamics, Inc.
Integrity Power Solutions
ISOPur Fluid Technologies, Inc.
ITH Engineering
JASC
K-Machine
Kinectrics
Koenig Engineering, Inc.
Lectrodryer, LLC
Macemore Inc
Marioff, NA
MD&A
Mee Ind. Inc.
Mercer Thompson LLC
Met Weld International
Mitten Manufacturing
Moog Industrial
National Electric Coil
Nederman Pneumafil
Nord-Lock Group
NRG Energy Services
OILKLEEN
ORR Protection Systems, Inc.
Paragon
Parker Hannifin
PGAS Inc.
PINNACLE PARTS AND SERVICE CORP
Pioneer Motor Bearing Company
Power & Industrial Services Corporation
Power Plant Services
Power Services Group
PowerFlow Engineering Inc.
Powmat Ltd
Precision Iceblast Corporation
PSM
Rapid Belts
Real Time Power INC
RelaDyne
Republic turbines
Reuter-Stokes, a Baker Hughes business
Riverhawk
Rochem Technical Services
Roper Pump Company
S.T. Cotter Turbine Services, Inc.
Schock Manufacturing
Shell Oil Products
Sohre Turbomachinery
Stork Turbo Blading
Sulzer
SVI INDUSTRIAL (BREMCO / SVI DYNAMICS)
Taylor’s Industrial Coatings, Inc.
Technical Training Professionals
TesTex, Inc.
Tetra Engineering Group, Inc.
Thomassen Amcot International “TAI”
TOPS Field Services LLC
Toshiba America Energy Systems
Trinity Turbine Technology
TTS
Universal Plant Services
Veracity Technology Solutions
Viking Turbine Services, Inc.
Voom, LLC
Young & Franklin

 

Easily connect with and view presentations from key suppliers @ 7FUG 2020, Part III

By Team-CCJ | March 10, 2022 | 0 Comments

One of the unique aspects of the 7F Users Group’s 2020 Digital Conference is the opportunity to interact online with the OEM and nearly 50 third-party solutions providers. Ten companies in the latter group were selected by the steering committee to conduct live technical presentations of one or two hours during Weeks Two, Three, and Four of the five-week program ending July 16.

The remaining solutions providers participated in the conference with virtual booths in the Vendor Fair conducted Tuesday and Wednesday of Week One. They connected directly with users via video (or audio) links.

In case you missed the opportunity to visit with one or more of these companies at the Vendor Fair, the editors have compiled brief summaries of the products/services they showcased, along with links to that information. The names of experts to contact for details are included.

Exhibitors not included in the list below were profiled in CCJ ONsite two weeks ago or last week, or will appear in our next edition. Products and services offered by virtual exhibitors Allied Power Group, GTC Control Solutions, Nel Hydrogen, Nitto Inc, Parker Hannifin Corp, Dekomte de Temple, Conax Technologies, Donaldson Company, ESC/Spectrum, and Hilco can be reviewed in Part I of this four-part series.

Part II of the series featured offerings from Mercer Thompson/IEM Energy Consultants, AP+M, Braden Filtration, Bureau Veritas, Groome Industrial Service Group, Pioneer Motor Bearing, VAW Systems, National Electric Coil, Nord-Lock Group, and Rochem Technical Services.

Liburdi Turbine Services

Case study of previously repaired 7FA first-stage turbine buckets

Justin Kuipers, a senior materials engineer with deep experience in gas-turbine component analysis and repair development, discusses the results of metallurgical analyses performed on four 7FA+e first-stage buckets. Each airfoil had been repaired by a different vendor using a different approach. The metallurgical condition and extent of the prior repairs are presented for each of the buckets following one additional service interval.

The 7FA+e presents demanding repair requirements. The first-stage bucket employs a hollow design with serpentine cooling passages, showerhead cooling along the leading edge, a tip cover plate, and welded and brazed details within the cooling passages. Such enhanced design features are conducive to challenging repairs with narrow tolerances—that is, less room for error. This calls for an increased reliance on metallurgical analysis for evaluating component condition, repair requirements, and qualification of repair results.

Key takeaways for users include the following:

    • 7FA first-stage buckets have characteristic damage modes.
    • Different shops have different repair strategies and processes, resulting in a range of possible outcomes from high-risk operation to good-as-new performance.
    • Internal coatings must be replaced to achieve multiple repair cycles.
    • Various heat treatments are used in repairs and they are important to understand.
    • Know the critical quality-control steps in component repair and how to reliably extend the service lives of valuable components.

Parker Hannifin Gas Turbine Filtration

Inlet air filtration solutions

Paul Barron, North American regional sales manager, and Sales Manager Abby Rowe met users in their virtual booth, updating them on the company’s line of inlet air filters and systems capable of superior performance over a wide range of environmental conditions. They reminded the owner/operators of the company’s two popular brands of filtration products: Altair® and clearcurrent™. Parker’s GT filtration options include the following: cartridge, vCell, pocket or panel filter. Complete gas-turbine inlet filtration systems, including evap coolers, also are offered.

Parker Hannifin was represented in two stands at the 7F Users Group’s virtual Vendor Fair. The company’s line of electrohydraulic servo valves, approved by GE for use on its gas and steam turbines, were promoted in the other booth and profiled in Part I of CCJ ONsite’s exhibit-hall coverage.

Moog Inc

Conceptual hybrid IGV positioning systems for large GE frame engines

Moog manufactures precision motion-control and positioning systems for gas and steam turbines, but may be known best to powerplant O&M personnel for its servo valves used to control hydraulic cylinders in many power-generation applications. Steve Beddick and Ken Kauppila teamed up to review hybrid electro-hydrostatic positioning systems and how they can be configured to replace the hydraulic IGV actuation systems sometimes associated with operational issues on GE Frame 6 and Frame 7 gas turbines.

Turbine Logic

Eliminating GT unplanned outages caused by combustion hardware and instrumentation failures

This presentation by Ben Emerson, manager, combustor and hot section, at Turbine Logic, and senior research engineer in Georgia Tech’s School of Aerospace Engineering, introduces a novel combustion-dynamics monitoring algorithm and a case study to demonstrate its successful detection of a gas-turbine combustor fault. Recall that combustor faults can cause expensive damage to both combustor and hot-section components.

These failures often develop from small, insipient faults which product subtle signatures in the combustion-dynamics data. Fault signatures can be detected by advanced monitoring algorithms before parts fail and force the unit out of service.

The algorithm described in the presentation, developed in conjunction with EPRI, blends data analytics with combustion domain expertise. It is fielded on a fleet of frame units and has caught several faults at sufficiently early stages to plan repairs without a forced outage. Emerson presents an overview of the algorithm’s core logic, enumerates the types of faults that the algorithm commonly catches, and closes with a detailed case history.

AP+M

T2020 bi-phase compressor cleaner

AP+M had two booths at the 7F Users Group’s virtual Vendor Fair. Last week, the company’s “Outage in a Box” consumable kit solution for GE Frame 6B, 7E, and 7F engines was included in CCJ ONsite’s event coverage; this week, AP+M’s compressor cleaning solution is featured.

Craig Sonnenberg and Jerrod Walters connected for a deep dive into the features of the company’s water-based T2020 bi-phase compressor cleaner, an advanced product with solvent cleaner characteristics but without the hazards associated with solvent cleaners.

Strategic Power Systems Inc

Powerplant analytics and optimization

Salvatore A DellaVilla Jr, founder and CEO of SPS is one of relatively few industry executives who needs no introduction. His deep knowledge of gas turbines goes back to the ordering boom that followed the Great Northeast Blackout of 1965. Most recently, DellaVilla was appointed managing director of the Gas Turbine Association.

His presentation at the virtual Vendor Fair was about ORAP®, Strategic Power Systems’ powerful database system that allows for the capture of data from powerplants operating worldwide and provides the value-added tools to support effective O&M decision-making.

Every powerplant requires data to make informed decisions and to satisfy its numerous reporting requirements, DellaVilla says. While a tremendous amount data are available, organizing it, and then transforming it into actionable information can be difficult and time-consuming. That’s what ORAP does.

Case histories incorporated into the presentation highlight ways owner/operators have used ORAP to create an information architecture within their businesses—including RAM, KPIs, and benchmarking; critical- and capital-parts planning, and automation to optimize time and productivity.

Listen to DellaVilla and come away with the following:

    • How to use data and analytics to drive down costs and improve productivity.
    • Satisfy all management, ISO/NERC GADS, and other reporting requirements with one set of data.
    • Benchmarking: Learn how you stack up against your peers.
    • Optimize your availability: Use data to stop issues before they happen.
    • Ensure knowledge transfer and consistency across multiple plants.
    • Transparency and lessons learned: Don’t repeat mistakes.
    • Identify problems in the fleet that you might not have experienced yet.
    • Have a complete perspective of your serialized parts—in operating units and inventory—including ageing over time.

C C Jensen, Oil Maintenance

Remote oil condition monitoring as a CBM tool including varnish—an update

Has Axel Wegner ever missed an opportunity to speak before a group of powerplant owner/operators about his passion—lube-oil condition monitoring and filtration? Certainly not in the last 10 years. If you have not listened to the solutions-oriented chemical engineer and want to learn how to deal effectively with the following problems:

    • Turbine oil varnish.
    • Particles and water in lube oil.
    • Bacteria, diesel bugs, fungi, particles, and water in backup diesel storage tanks for dual-fuel plants.

Listen to the presentation he recorded for the 7F 2020 virtual Vendor Fair. You might even consider showing it to the plant O&M staff during a lunch-and-learn session.

Wegner points out that the “right” condition-monitoring and filtration system for any machine and oil type allows you to identify problems remotely and to take action before problems occur.

Badger Industries

Consolidate exhaust-system maintenance to reduce costs and maximize runtime (users only)

Operations Manager Matt Long and Field Service Manager Gary Neimann team up to highlight Badger’s service options for streamlining the maintenance of exhaust-system components from the turbine to the HRSG. Highlights of the presentation include these:

    • The value proposition for upgrading the flex seal rather than opting for the OEM’s leaf seal replacement.
    • Repairs available for the A042 diffuser duct for increased thermal efficiency and longer life.
    • Single-source provider for expansion joints and service labor.

The company’s products/services include the following: turbine exhaust expansion joint, 7F flex-seal upgrade, A042 diffuser duct, HRSG inlet expansion joint, pipe penetration seals, thermographic analysis, and failure analysis.

Emerson Automation Solutions

Advanced condition monitoring with Ovation (users only)

Jason King, machinery health solutions manager, discusses how turbomachinery protection and condition monitoring can be accomplished on the same platform as the turbine controls, providing automated diagnostics to operators without requiring them to learn vibration analysis. For vibration analysts, onsite or at a remote diagnostics center, full-featured analysis capability is possible while still meeting cybersecurity requirements.

SVI Dynamics

Defining and implementing SCR improvements on gas-turbine exhaust (users only)

Stringent regulations on NOx, CO, and ammonia slip are dictating the need for highly efficient SCR systems. Although CO and SCR catalyst designs are advancing to meet these new regulations, SCR system designs are not always equipped to manage the performance requirement improvements.

Industry veteran Bill Gretta, SVI Dynamics’ SCR product-line director, understands. His company, he says, has incorporated years of knowledge and experience gained from work on SCRs manufactured by all of the major vendors into SVI’s new SCR. If new is not optimal, SVI can provide in-depth analysis of your SCR to suggest enhancements that will improve reliability and efficiency.

Part of Gretta’s presentation illustrates the benefits of CFD modeling in guiding performance upgrades. He also explains how SVI would conduct a design review of your system and how to develop a PM inspection plan for your SCR.

Easily connect with and view presentations from key suppliers @ 7FUG 2020, Part II

By Team-CCJ | March 10, 2022 | 0 Comments

One of the unique aspects of the 7F Users Group’s 2020 Digital Conference is the opportunity to interact online with the OEM and nearly 50 third-party solutions providers. Ten companies in the latter group were selected by the steering committee to conduct live technical presentations of one or two hours during Weeks Two, Three, and Four of the five-week program ending July 16.

The remaining solutions providers participated in the conference with virtual booths in the Vendor Fair conducted Tuesday and Wednesday of Week One. They connected directly with users via video (or audio) conferencing platforms. They also provided recorded technical presentations for users to access on-demand throughout the year, which can be viewed below.

In case you missed the opportunity to visit with one or more of these companies at the Vendor Fair, the editors provide below brief summaries of the products/services they showcased along with links to that information. The names of experts to contact for details are included.

Suppliers not included in the list below either appeared last week (Allied Power Group, GTC Control Solutions, Nel Hydrogen, Nitto Inc, Parker Hannifin Corp, Dekomte de Temple, Conax Technologies, Donaldson Company, ESC/Spectrum, and Hilco) or will be profiled in CCJ ONsite before our coverage of the 7F meeting concludes on July 20.

Mercer Thompson LLC and IEM Energy Consultants

Ensuring your LTSA is fit for the future

Many owners are rethinking their LTSAs given the proliferation of renewable resources challenging the operation of traditional fired assets. Jason Yost of Mercer Thompson, a frequent speaker at user-group meetings, and IEM Energy Consultants’ Bill Ray and Craig Nicholson, say contracts negotiated years ago may not be calibrated for future needs. The speakers discuss some of the key areas and potential opportunities to consider, plus steps that can be taken to ensure owners are best positioned to effectively negotiate or renegotiate their LTSAs. Takeaways include negotiating strategies, best practices, and how to avoid common and costly pitfalls in the negotiation process.

AP+M

“Outage in a Box”consumable kit solution for GE Frame 6B/7E/7F engines

Craig Sonnenberg and Jerrod Walters combined for a deep dive into AP+M’s “Outage in a Box®”—one or more containers containing all the consumables required onsite for maintenance outages. The custom, cost-effective packages are delivered directly to the outage site. Walters and Sonnenberg say the company can provide a wide variety of parts from its global network—including engine, package, and BOP parts and components, inlet evap cooling misting nozzles, inlet filters, etc. Services offered include replacements of control, engine-support, and BOP systems.

Braden Filtration LLC

Advancements in nanofiber technology for pulse filters    

If you’ve ever ordered gas-turbine inlet filters, you likely know the name Mcleod Stephens. He’s been serving users for four decades in management positions at three filter manufacturers. But what you may not know is that in the last year Stephens helped to form Braden Filtration LLC, where he is general manager, after purchasing the manufacturing assets from Braden Manufacturing parent Innova Global.

He discusses how the technology of nanofiber manufacturing and application has improved over the years, and how those changes and improvements—targeted at pulse-type air-inlet systems—came about and why. Takeaways for users include the following:

    • How filter life can be impacted positively by new, contemporary nanofiber applications.
    • How flow resistance is reduced.
    • How pulse-cleaning frequency can improve service life.
    • How recent design changes to the media substrates contribute to better performance.

Bureau Veritas

Adjusting turbine-oil monitoring to the current situation

Jorge Alacorn, senior consultant and thought leader on the subject of “Reliability through Oil Conditioning Monitoring and Predictive Analytics” as applied to maintenance, focuses Texas-based Bureau Veritas’ presentation on how to maximize the life of turbine oil by combining appropriate condition tests based on the application, risk of failure, and plant reliability objectives.

He and colleagues Jeremy Erndt and Barry Cato, help owners/operators:

    • Select the correct oil analysis for their plants.
    • Understand the importance of a proper oil analysis.
    • Use oil condition monitoring as a predictive tool to avoid a turbine shutdown.

Services offered by the company include oil condition monitoring, plant lubrication audits, boiler and pressure-vessel inspection, ISO 15001 auditing and training, and leak detection.

Groome Industrial Service Group LLC

AIG tuning and permanent sampling grid

Jeff Bause and Steve Houghton explain how Groome’s turnkey services enable owner/operators to reduce harmful emissions, improve plant performance, and extend the lifetimes of critical equipment. They go on to say the company’s philosophy is simple: Provide quality, innovative services at a reasonable price for its five maintenance service lines—HRSG and refinery maintenance, industrial cleaning and support, surface preparation and coatings, and door and mechanical services.

HRSG maintenance, the service line of greatest interest to 7F users, is supported by strategic alliances with industry experts and catalyst manufacturers to ensure Groome offers the most widely supported and comprehensive turnkey services available in the industry. Specific services include the following:

    • SCR catalyst systems.
    • CO catalyst systems.
    • AIG systems and controls.
    • Retrofit and installation.
    • Boiler tube cleaning.
    • Industrial coatings.

Pioneer Motor Bearing Co

The “care and feeding” of fluid-film bearings

Dr Lyle Branagan, Pioneer Motor Bearing’s engineering manager, is well respected in the electric-power community for his deep knowledge of bearings. Branagan’s 7F presentation focuses on damage mechanisms found in fluid-film bearings for motors, turbines, and generators. Topics including theory of operation, bearing design features and materials of construction, and lubrication basics are reviewed in brief at the beginning of the presentation. This information serves as a backgrounder for the ensuing discussion of some typical damage mechanisms observed in today’s bearings—with an eye toward prevention of recurrence and recovery from the problem.

Branagan’s goal is to give attendees the ability to examine post-service bearings with a better perception as to how markings and damage to the bearing surface would affect continued operation and long-term reliability. Owner/operators will come away with an ability to relate those damage markings to some specific degraded conditions in the machine—such as shaft currents and misalignment.

Pioneer Motor Bearing specializes in the repair and service of large oil-lubricated bearings, with a focus on engineering problem-solving. The company, a license of Siemens Energy, GE, and the UK’s Mitchell Bearings, may be best known to users for its Babbitt-bearing repairs, new manufacture, reverse engineering, upgrades and custom designs, and technical support.

VAW Systems Ltd

Exhaust system retrofit approach

VAW Systems’ core business is the design and manufacture of engineered noise control products for gas turbines, fans, steam vents, and other applications. Dominic Crnkovich and Dennis Seltz introduce owner/operators to the company’s line of silencers, filtration systems, and related components that promise to meet the high performance and quality demands of modern powerplants. The speakers say users can expect high acoustic performance within a relatively small footprint, plus low pressure drop in applications requiring that.

Segments of the presentation likely to be of greatest interest to users is an overview of exhaust-system failures and new challenges, the company’s approach to exhaust-system repair/replacement, and improvements for system longevity. 

National Electric Coil

An improved self-locking amortissuer finger and spring assembly for 7FH2 generator rotors

Bill Harris, NEC’s field services manager for rotating electrical equipment, presents on the importance to generator reliability of the Inconel Spring incorporated into the amortisseur/damper segment of 7FH2 rotors.

The Inconel Spring, he says, is prone to traveling on an axial migration path towards the retaining ring. Migration can lead to blocked cooling passages and the further effects of uneven heating across the rotor. Additionally, if the Inconel Spring makes its way under the retaining ring, damage to retaining-ring insulation can result—possibly even a ground fault.

Harris reviews the mechanisms of spring migration on the rotor components during operation and explains the structure and important function of the rotor’s amortisseur/damping system.

NEC is a company that needs no introduction to most powerplant owner/operators. It specializes in shop and onsite repair and upgrade services for generators and rotating exciters of all makes and models and sizes. NEC also is an experienced winding manufacturer.

Nord-Lock Group

Coupling-bolt issues and solutions with EzFit

Steve Brown, Nord-Lock’s resident expert on expansion bolts, shows how a technology that has proven effective in critical power-generation applications is eliminating the costly, time-consuming challenge presented by seizure-prone fitted coupling bolts during outages. It highlights recent cases that demonstrate the technology’s value in the field. Plus, it offers preemptive steps that plant personnel can take to minimize flange-bolt faults in future maintenance situations.

Brown presents on the downsides and risks of using conventional bolts for turbine/generator coupling and helps users better understand the principles of mechanical expansion bolts—what they are, how they work, and how they mitigate the problems associated with conventional bolts.

Rochem Technical Services

Compressor cleaning best practices

Following an introduction by Managing Director Martin Howarth, Steve Engelhoff, a familiar face at user meetings in the US, discusses cleaning best practices based on the company’s technical expertise and field experience. Recall that Rochem offers a range of gas-turbine cleaning systems, precision-designed nozzles, and specialist compressor cleaning chemicals to help keep GTs operating a peak efficiency. The company’s Fyrewash products are designed to address all types of fouling and to meet OEM and environmental standards worldwide

Easily connect with and view presentations from key suppliers @ 7FUG 2020

By Team-CCJ | March 10, 2022 | 0 Comments

One of the unique aspects of the 7F Users Group’s 2020 Digital Conference is the opportunity to interact online with the OEM and nearly 50 third-party solutions providers. Ten companies in the latter group were selected by the steering committee to conduct live technical presentations of one or two hours during Weeks Two, Three, and Four of the five-week program ending July 16.

The remaining solutions providers participated in the conference with virtual booths in the Vendor Fair conducted Tuesday and Wednesday of Week One. They connected directly with users via video (or audio) conferencing platforms. They also provided recorded technical presentations for users to access on-demand throughout the year, which can be viewed below.

In case you missed the opportunity to visit with one or more of these companies at the Vendor Fair, the editors provide below brief summaries of the products/services they showcased along with links to that information. The names of experts to contact for details are included.

Suppliers not included in the list below will be profiled in CCJ ONsite before our coverage of the 7F meeting concludes on July 20.

Allied Power Group 

Introducing APG Nexgen™ combustion technologies

APG President Jim Masso reviews the company’s recent acquisitions—Nexgen (advanced fuel systems), Texas Metal Printing (3D printing of turbomachinery components), and Eta Technologies (largest non-OEM V-series engine component and repair supplier)—and then summarizes the company’s capabilities in NDT, metallurgy, chemical stripping, grit blasting, rotor repair, and onsite field service. APG’s coating technology and capabilities are discussed next along with comprehensive combustion repair. A shop tour is included.

Custom engineered solutions for F-class owner/operators follow—including problem diagnosis and RCA capabilities, calibration and flow testing, and parts reconditioning. A technology solution of interest to many users is the company’s brazed insert replacement for the 7FA fuel nozzle. Engineered solutions include output and firing-temperature increases, 7FA.04 repairs, life extension, etc.

GTC Control Solutions

Operational tips through case studies, TIL 1524 and 1275 implementations, LVDT calibration

Chief Engineer Abel Rochwarger, respected by many in the industry for his controls expertise (and his unique brand of comedy), helps users understand the factors that determine “single points of failure” and how to identify them, plus the not-so-evident aspects of the relevant Technical Information Letters that can be learned only after implementation.

The takeaways: Users with Mark VI controls will learn about previously unknown/undisclosed failure modes, how to determine if their control systems are potentially susceptible to them, and what the options are for avoiding future occurrences. Personnel from plants with Mark V controls will come up to speed on two new cards from GTC that can help extend the lives of their panels.

Bonus discussion: Average versus core-by-core LVDT calibration.

Nel Hydrogen

Hydrogen generation ensures reliable hydrogen supply for CCGT powerplants

Dave Wolff discusses the use of onsite hydrogen gas generation as a safer, more economical alternative than delivered hydrogen for generator cooling. Users will gain an understanding of how ultra-pure, pressurized, dry hydrogen gas is produced onsite from electricity and water using the company’s compact Proton Exchange Membrane electrolyser. Applicable system drawings are included.

Nitto Inc

Introducing hydrogen detection tape

The physical properties of hydrogen gas make leaks extremely difficult to detect. Finding leaks quickly is important to ensure personnel safety and to protect critical plant assets. Dr Nahid Mohajeri, GM of advanced polymer technology at Nitto, explains the company’s industrial-grade adhesive tape, which is applied to hydrogen-system components most likely to leak—such as flanges. The tape changes color from amber to black when exposed to even the smallest amounts of hydrogen—concentrations of 1%, for example. Powerplant experience is shared along with lessons learned.

Parker Hannifin Corp – Energy Division

Reduce maintenance concerns and costs associated with gas-turbine fuel control valves

Jim Hoke, Parker’s capital projects manager for power generation, provides users technical information on the company’s line of electrohydraulic servo valves required for decision-making. The valves are approved by GE for use on its gas and steam turbines for the following applications: control of gas and liquid fuels, steam-valve actuators, inlet guide vanes, and stop/ratio actuators.

Key takeaways from the presentation include these:

    • Parker’s “soft-fail” electrohydraulic servo valves if plugged will not cause the downstream actuator to fully extend or retract—it will remain in place. However, the valve can be spring-biased to move the actuator to a preferred safe position.
    • The product is a drop-in replacement for many servo valves in use—including hydraulic mounting and electrical connections.
    • Large orifice diameters allow contaminants to pass through instead of obstructing flow.
    • Hydraulic spool, designed with a significant chip shear force, enables continued operation in hydraulic systems experiencing varnish buildup.
    • The robust design allows extended intervals between PMs, calibrations, and tests.

Dekomte de Temple

Fabric expansion joint solutions for 7F CCGT plants

Jake Waterhouse, group technical director at Dekomte, is a frequent speaker at user-group meetings. Here he discusses the benefits of retrofitting the 7F flex seal, used where the diffuser transitions to the cold casing, with a high-quality fabric solution for longer life and greater durability in cycling plants. Other applications for fabric expansion joints include the HRSG inlet and outlet.

Inspection (visual and thermographic) is the first step in understanding the existing condition and technical requirements to develop a tailored long-term reliable solution, says Waterhouse. Another input to the decision-making process is a review of operational criteria to identify to the degree possible expected operating parameters going forward.

Waterhouse shows with drawings and photos the details of the company’s expansion-joint offerings and presents case studies to illustrate the challenges posed by different gas-turbine models and the successful solutions implemented.

Conax Technologies

Power Division capabilities overview

If you’re unfamiliar with Conax Technologies, which manufactures temperature sensors, compression seal fittings, and cable harness assemblies, watch the 2-min video for an overview of the company’s capabilities and products for generating plants. In addition to standard off-the-shelf products, custom-engineered solutions are available to address the industry’s most demanding challenges.

Here’s a shortlist of products and services available from Conax:

    • Exhaust-gas thermocouples.
    • Sensor cable assemblies.
    • Bearing temperature sensors and seal feedthroughs.
    • Temperature-sensor harness assemblies.
    • Vibration analysis, accelerated lifecycle qualification testing.

Donaldson Company, Gas Turbine Systems

Technology solutions providing more power to you

Donaldson’s Casandra Light and Mike Carlson walk you through the company’s Three Pillars of Filtration methodology focusing on efficiency, water tightness, and pulse recovery rate to provide your plant the optimal filtration solution. Case histories illustrate the value in adopting Three Pillars.

ESC/Spectrum

Optimizing your data acquisition system with StackVision: Best practices, sound advice

Andy Taer brings you up to date on the Austin (Tex) company and its data acquisition system software—including StackVision™ and SpectraView® Prism—for continuous emissions monitoring systems.

Products and services, in addition to the DAS software, include the following:

    • Software IT services—including hosting, upgrades, and system migration server management.
    • Software customer support, documentation, and training services.
    • 8864 Data Controller hardware.
    • CEMS maintenance and training.
    • Stack testing for RATA, permit compliance, and engineering studies.
    • Repair and calibration of CEMS equipment.
    • Mobile testing systems and parts for CEMS.
    • Compliance reporting services.

Hilco

Coalescer separator, oil mist eliminator help bring fluid contamination problems under control

Two short videos illustrate how the company’s equipment works and the results it offers in terms of water and contaminant removal. Hilco goes beyond filters to provide a full-service fluids-management process—from obtaining samples to analysis to consulting to field service.

The total oil maintenance service offered by the company contributes to a reduction in new oil purchases, lower disposal costs, less wear of lubricated parts, and less downtime.

Team Hilco posits that the reliability and efficiency of any filtration system depends chiefly on cartridge quality. The company offers a full line of cartridges for virtually every application—depending on size, filtration efficiency, and dirt-holding capacity. Most fluids serving in powerplants generally can be restored to a like-new condition. Hilco’s world-class laboratory offers a full suite of test capabilities to support industrial filtration and fluid analysis.

Easily connect with and view presentations from key suppliers @ 7FUG 2020, Part IV

By Team-CCJ | March 10, 2022 | 0 Comments

One of the unique aspects of the 7F Users Group’s 2020 Digital Conference is the opportunity to interact online with the OEM and nearly 50 third-party solutions providers. Ten companies in the latter group were selected by the steering committee to conduct live technical presentations which are available for on-demand playpack. The remaining solutions providers participated in the conference with virtual booths in the Vendor Fair conducted Tuesday and Wednesday of Week One. They connected directly with users via video (or audio) links.

In case you missed the opportunity to visit with one or more of these companies at the Vendor Fair, the editors have compiled brief summaries of the products/services they showcased, along with links to that information. The names of experts to contact for details are included, in addition to a variety of downloadable case studies, white papers, etc.

Part I. Exhibitors not included in the listing below were profiled in CCJ ONsite earlier. Products and services offered by virtual exhibitors Allied Power Group, GTC Control Solutions, Nel Hydrogen, Nitto Inc, Parker Hannifin Corp, Dekomte de Temple, Conax Technologies, Donaldson Company, ESC/Spectrum, and Hilco can be reviewed in Part I of this four-part series.

Part II of the series featured offerings from Mercer Thompson/IEM Energy Consultants, AP+M, Braden Filtration, Bureau Veritas, Groome Industrial Service Group, Pioneer Motor Bearing, VAW Systems, National Electric Coil, Nord-Lock Group, and Rochem Technical Services. [link to

Part III of the series summarized offerings from Parker Hannifin Gas Turbine Filtration, Moog Inc, Turbine Logic, AP+M, Liburdi Turbine Services, Strategic Power Systems Inc, C C Jensen Oil Maintenance, Badger Industries, Emerson Automation Solutions, and SVI Dynamics.

JASC Controls

Pitfalls to avoid for enhanced liquid-fuel-system reliability (users only)

Schuyler McElrath, one of the electric-power industry’s leading experts on liquid fuel systems for gas turbines, has new product development as one of his responsibilities at JASC Controls. His presentation simplifies the complexity inherent in liquid fuel systems and focuses on what design features owner/operators should be aware of to assure reliable starts on oil, reliable transfers from gas to oil, and vice versa, and reliable operation on both fuels. McElrath stresses that while some issues can be addressed with hardware upgrades, system infrastructure changes are an equally important part of the performance improvement process.

ARNOLD Group

Advanced steam-turbine-casing warming for startup (users only)

ARNOLD is perhaps best known globally for the insulation systems it provides for all types/designs of gas and steam turbines. Outside North America it is equally well known for its onsite turbine machining services. Turbine warming systems have matured as product line in the last several years given the need for gas and steam turbines to start faster to satisfy grid requirements.

Pierre Ansmann, the company’s global head of marketing, Norman Gagnon, ARNOLD’s North American project manager, and controls expert Joris Ringelberg provide users a primer on turbine warming systems. Their presentation covers the following:

    • Maintenance and operational benefits for individual customers.
    • Differences between various warming-system arrangements.
    • Durability and reliability.
    • The importance of proper insulation for a warming system.
    • Warming-system controls.
    • Cost and duration of initial installation and periodic maintenance.

Sulzer

A look inside Sulzer Turbo Services (users only)

Michael Andrepont, GM operations (gas turbines), and Jim Neurohr, area sales manager, take you on a 6-min tour of Sulzer Turbo Services’ Houston shop and explain the company’s capabilities regarding the 7FA—including HGP component, combustion hardware, and fuel-nozzle repairs, field services, rotor life evaluation, LTSAs, etc. Sulzer is one of the world’s leading independent service providers in the repair and maintenance of all makes and models of industrial gas and steam turbines, compressors, and expanders. It offers a wide range of manufacturing, engineering, reconditioning, balancing, and coating services.

HRST Inc

GT upgrades: Low-load impact on HRSGs (users only)

Anand Gopa Kumar, who leads HRST’s Analysis Dept, provides users critical insights on how increasing the turndown capability of their gas turbines to provide the operational flexibility required in many areas of the country today may impact the HRSG. He identifies areas within the boiler at risk of exceeding their design capabilities and possibly susceptible to long-term damage. Kumar also suggests modifications to the HRSG and associated equipment (including attemperators, internal liners, superheater tubes, steam separators, etc) to enable the desired turndown with minimal risk.

MD&A

7FA component lifetime extension (users only)

José Quiñones, PE, director of engineering for MD&A’s San Antonio Service Center, the company’s gas-turbine parts service facility, presents a tutorial on the life-limiting factors of hot-gas-path components. Included are typical steps to follow when conducting a lifetime-extension project. Plus, the upgrades, mods, and improvements—including advanced coatings—you should consider to extend the lifetimes of critical parts.

Gas Path Solutions LLC

Exhaust-diffuser relining and upgrades (users only)

Brian Nason, business manager, and Michael Busack, sales and field services manager, discuss the reconditioning services and upgrades offered for 7FA exhaust diffusers manufactured by C&W Fabricators, Quest, Braden, and others. Among the company’s replacement solutions: inlet flex seal joint, outlet expansion joint, and internal free-floating liner system. Turnkey installation is provided.

Koenig Engineering Inc

Everything you should know about turning gears but don’t (users only)

Tim Connor, aftermarket sales and field service manager, reviews findings from turning-gear teardown inspections, highlighting common failure modes and how to avoid them. An in-depth review of turning-gear operation and major components is especially beneficial for plant personnel with limited experience. Finally, Connor offers an action plan for ensuring long-term turbine starting and rolling reliability.

ExxonMobil

Pushing the needle: New strategies to improve gas-turbine energy efficiency through lubrication (users only)

Lubrication experts Mike Galloway, Jim Hannon, and Charlie Smith show how oils offering energy-efficiency benefits can improve your bottom line. They dig into the technical science and offer field and lab data to quantify the value of advanced lubrication strategies.

EagleBurgmann Industries LP

Expansion-joint maintenance from an owner/utility perspective (users only)

Mark Ahonen, aftermarket sales manager, provides an in-depth look at the 7FA exhaust joint—covering maintenance, repairs, upgrades, and a general owner’s guide of critical areas to monitor.

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