Vendor Presentation Notes (3 of 3)

“Vendorama” Adds another Dimension to the 501F and G Program, cont.

Braden Manufacturing LLC. Most vendor presentations at user-group meetings focus on a product or service and have a commercial bent. Bill Grace (bgrace@braden.com), who manages Braden’s aftermarket business, took a different approach. He offered a primer on inspection and commissioning of evaporative coolers that was of value to virtually all O&M personnel in attendance. An hour would have been about right for this presentation considering the amount of material covered and its importance to maximizing turbine output and performance.

Grace opened with a two-slide refresher explaining evap cooling and moved quickly into a laundry list of problems that can be avoided through regular maintenance. These issues were divided into three general subject areas: reduced or no cooling, water carryover, and sulfur corrosion (water carryover and sulfur in fuel are conducive to hot-gas corrosion).

He spent nearly half of the allotted time on the causes of scale and dirt accumulation on/in media and how to avoid these robbers of performance. Identification of unwanted water carryover and what corrective action to take was another major focus by Grace, covering drift eliminators, splash covers, proper water distribution, etc.

Alta Solutions Inc. manufactures sensors, monitors, analyzers, and software used in many of the combustion dynamics and vibration monitoring/analysis systems installed on large gas turbines—including nearly 60% of engines in the 501F fleet, as well as on a handful of Gs.

The presentation, which focused on the company’s products and their capabilities, probably was of greatest value to personnel new to F-class plants who had limited or no experience in CDMS. The technology certainly is an eye-opener for those who spent most of their careers operating and maintaining engines with grandfathered emissions permits.

A focal point of the presentation was Alta’s AS-320 rotating machinery monitor which offers real-time machinery protection. The company promotes the AS-320 as the next generation of vibration protection systems with all the capabilities of a rack-based protection system in a modular, cost-effective package. It supports a wide range of vibration inputs—including accelerometers, displacement probes, pressure sensors, phasemarkers, microphones, and velocity pickups.

Liburdi Turbine Services Inc. Doug Nagy, PE, manager of component repair, knew he couldn’t turn attendees into metallurgists in the 20 minutes allocated for his presentation, so he did the next best thing: He helped them focus on HGP repair decisions to extract maximum value for the plant owner. Three key points Nagy made:

  • Metallurgical analysis enables you to determine the                                                     optimum service interval for hot-section parts. Parts removed too soon waste resources and outage time, those run too long cannot be repaired economically.
  • Effective repairs require knowledge of the metallurgical damage mode(s). Absent this information, repair efforts may be misguided. To illustrate: Cracks in the lower trailing edge of turbine blades are caused by thermal-mechanical fatigue. Blending and/or weld repair is not a solution. What needs to be done: Increase the compliance of the part to make it strain tolerant. This suggests engineer modeling.
  • During the repair process, there can be opportunities to improve components. Guidance from metallurgical analysis identifies these opportunities. For example, Nagy said, Liburdi often substitutes or adds coatings when surface attack limits service interval or component life.

Contact Nagy at dnagy@liburdi.com.

Advanced Turbine Support Inc. Perhaps no borescope inspection team in the industry has seen the inside of more gas turbines than Rod Shidler and Rick Ginder. They know what types of damage to look for and where to look in virtually every engine model; F-class machines are their specialty.

501F R2 blade failure

With R2 the hot topic at the 501F meeting in San Diego, it was not surprising that Shidler ran through the basics of a general condition assessment for that row with focus on the trailing-edge platform and tip. A previous post on CCJ ONsite discussed the R2 issue in depth in the 501F Special Report.

Shidler said ATS inspection reports identify the location and measurements of any cracks or other damage on every blade in the row. He added that company data show all cracks identified thus far have occurred in OEM blades with more than 20,000 total service hours.

Next, Shidler showed a series of photographs revealing where you can expect to find R2 cracks are found and what they look like. The longest ATS identified during an inspection was nearly an inch in length; the OEM suggests removing blades if cracks exceed 0.4 in. long. Contact atsrodshidler@yahoo.com.

KE-Burgmann USA Inc. At most user-group meetings you’ll catch Paul Schubert and General Manager Mike Green walking a maintenance manager through Burgmann’s welding procedures for dealing with exhaust-system cracking.

Green didn’t cover that topic during the company’s Vendorama slot as the editors expected. Rather, he offered an insightful presentation on the company’s work to develop what Green called the most advanced turbine exhaust expansion joints in the industry today. He began by talking about the need for new solutions to accommodate higher operating temperatures, more thermal cycles, longer service intervals, etc. Then Green discussed the company’s research to identify “breakthrough” materials—including a ceramic-free, bio-soluble insulation—to extend the lifetimes of expansion joints and penetration seals in the face of the more demanding service conditions.

Critical to Burgmann’s efforts is a test bed that                                                               simulates “real world” operating conditions for high-temperature expansion joints. Green said, “We can test drive new materials to determine their life expectancy. We have learned that thicker isn’t always better.” A series of test rigs, including vibration, low-cycle fatigue, and high-cycle fatigue (photo) illustrated how the company goes about assuring product quality.

Green closed with a series of slides showing the details of Burgmann’s new expansion joints for the 501 F and G engines. Write Green for details at mgg@kebusa.com.

Process Control Solutions Inc. If you’re managing plant that would benefit from a controls upgrade and you get a bit apprehensive when thinking about it, consider yourself normal. The lingo alone is a challenge. If you get serious about a system upgrade or replacement, a point to keep in mind is that the OEM is not your only option.

For example, 501F and G users might have to migrate away from a WDPF or TXP platform to accommodate a turbine performance upgrade. One choice would be the OEM’s T3000. An alternative is Ovation™. For an Ovation migration you could go the third-party vendor route or hire an independent like Mitch Cochran, a frequent presenter at user-group meetings.

Cochran was on hand at Vendorama to run through project management considerations to assure a successful Ovation migration. There was too much material to cover in a few words here. To get the details, access Cochran’s recent article in CCJ, Repair or upgrade, what’s the best strategy for your control system?

For more information, write mitchpcs@aol.com.

Posted in 501 F&G Users Group |

One response to “Vendor Presentation Notes (3 of 3)”

  1. […] Interestingly, this is about where Mitch Cochran of Process Control Solutions LLC began his Vendorama presentation on controls […]

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