Western Turbine Users – Combined Cycle Journal

Western Turbine XXII exceeds expectations

The 2012 edition of the world’s largest conference and exhibition for owner/operators of GE LM (land and marine) aeroderivative gas turbines, sponsored by the independent Western Turbine Users Inc, was held at the Pasadena (CA) Convention Center, Marh 18-21.

In terms of size, this was the second or third largest meeting in the all-volunteer user group’s history. With attendance approaching 900 as the conference started, second place was a possibility. More than 1200 persons attended the 20^th anniversary meeting in San Diego two years ago. On the exhibit floor, 146 companies were represented—the second most ever.

The Western Turbine conference is dominated by breakout sessions focusing on O&M issues for each of the gas turbines supported: LM2500, LM5000, LM6000, LMS100. There also are multiple tracks featuring presentations in special interest areas, as well as presentations of a general nature. Social events and meals round out the program.

Ramping up

This article covers topics from the Pasadena meeting of general interest to the LM community, and in some cases, owner/operators of other types of engines as well. Technical details are reserved for a special report in 3Q/2012 covering the specifics of the four engines.

President Jon Kimble of California-based Wellhead Electric Co started the meeting by reminding attendees why they were in Pasadena. The aero sector of the electric power industry is in a continual state of technical change, he said. Proof includes that in the last year, the OEM had issued more than 30 service bulletins for each of the LM6000 and LMS fleets. Keeping up with the issues and engine enhancements to maintain top performance is vital to all companies engaged in the competitive generation business.

Business matters were next. Kimble announced that Don Haine,s who manages the Panoche Energy for O&M contractor Wood Group Power Plant Solutions, had completed his three-year term on the Board of Directors and was being succeeded by Calpine Corp’s Andrew Gundershaug. Haines continues as chairman of the LMS100 group within WTUI; Gundershaug is the LM5000 chair.

Also, Bryan Atkisson, recently appointed a plant manager by Riverside Public Utilities, retired as chairman of the LM6000 breakout after five years at the helm following the meeting. David Merritt of Kings River Conservation District, a member of the board of directors, replaced Atkisson.

Click through to our special WTUI coverage:

1. HEPA filters eliminate compressor washing

2. OEM requires tracking of cycles on LM engines

3. Most advanced LMS 100s, LM 6000s in service power year’s first GT

4. One way to quickly remove water, particulates from turbine oil

The depots

The success of the Western Turbine meeting is underpinned by the technical and financial support of the five depots licensed by the OEM to inspect and repair the four engines addressed by the group. TransCanada Turbines (TCT), Calgary; MTU Maintenance Berlin-Brandenburg GmbH, Ludwigsfelde, Germany; Air New Zealand Gas Turbines (ANZ), Auckland; Avio SpA, Rivalta de Torno, Italy, and IHI Corp, Tokyo.

Representatives of the depots work closely with the WTUI leadership to prepare “lessons” for each of the breakout sessions. Deliverables include notebooks, given to participants, which review recent service bulletins and service letters issued by the OEM; a summarize depot findings since the last meeting; explain causes of performance loss and how to correct them; and provide the fundamentals of critical-parts life management.

The knowledge contained in the notebooks, and that shared by LM experts during the meeting, provide comprehensive, low-cost training for all those involved in the operation, inspection, and maintenance of aero engines. Electric power generators obviously agree with the value proposition offered by Western Turbine because each year first-timers comprise between one-third and one-half of the user attendees.

Each depot provided a thumbnail sketch of recent activities during the opening session of the meeting. Here are key take-aways, most related to new repair facilities:

IHIExecutive Officer Hiroyuki Otani reiterated President/CEO Kazuaki Kama’s commitment to world-class support of US LM6000 users despite the challenges of the Fukushima disaster which impacted production at one of the company’s shops for a couple of months. Since that time, IHI has expanded and improved the efficiency of its Mizuho and Kure No. 2 Works. It has also opened a Level 2 shop in Cheyenne with Wyoming-based Reed Services Inc.
TCT’s presentation by Darcy Simcinelli, director of customer support, and Dale Goehring, director of customer support and GE projects, focused on the company’s overhaul and repair facilities and capabilities for the LM6000 and LM2500 fleets. Most impressive of its shops is the 225,000-ft2 Airdrie plant about 20 minutes north of Calgary by car. It features an automated clean line, 21 overhead cranes, nine balancing machines, space for component repair in the future, and truck bays to facilitate loading and unloading.

Other service facilities in the company’s portfolio, most opened within the last few years: Houston, Bakersfield, Syracuse, Cumbernauld (UK), Singapore, and Perth (Australia). These range in size from about 4000 to 15,000 ft2 and were referred to as “hospital shops” for small jobs. Next facility to open (before July) will be an LM6000 test facility being installed alongside the company’s existing test cell.

MTU’s Ludwigsfelde facility is the company’s center of excellence for the repair of industrial gas turbines. It is equipped to inspect and repair all types of GE LM2500/5000/6000 engines. This lead facility works closely with company shops in Hannover and Munich, Germany, and in Kuala Lumpur—and most recently the New Braunfels (Tex) plant, which opened in 2010, and a Level 2 facility in Thailand, which opened in June 2011. Yet another shop is planned for Brazil.
Avio reviewed the inspection and repair capabilities of its Turin and Brindisi facilities and announced that a new division, AvioService, was established in July 2011.
ANZGT reported that it had invested significant resources in the last year to develop a field service office in Bakersfield, Calif, and a global field service team. Western Turbine veterans Frank Oldread and Jimmie Wooten, former directors of the user group, were introduced as the general manager and field service supervisor, respectively, for the Bakersfield facility.

The company’s depot, based at Auckland International Airport, provides full Level 4 overhaul capability, module exchanges, engine testing, failure analysis and investigation, and in-house repairs for LM2500 and LM5000 engines. ANZGT also manages critical LM5000 parts for the OEM.

Breakout overview

A common thread running through the LM2500, LM5000, LM6000, and LMS100 breakout sessions during the two-and-a-half-day meeting was that current issues typically were carryovers from previous meetings; relatively few new problems were reported. However, that the issues were not “new” did not detract from the level of interest, primarily because of the high percentage of first-timers. In fact, a couple of the breakout sessions ran half an hour beyond the official 5 p. m. closing bell on the first day of the meeting.

LM2500. John Baker, the plant manager for a 1 x 1 LM2500-powered combined cycle owned by Riverside Public Utilities, chaired this breakout with help from the OEM and representatives of TCT, ANZGT, Avio, and MTU for all but the user-only sessions.

The depots reported seeing many issues in the last year that had been addressed previously. They were of the general opinion the repeat problems were being experienced because users were not proactively accessing and reading service bulletins and letters, product bulletins, and OEM manuals posted on the GE customer website.

Recall that the OEM now delivers documentation for its customers via the Web. Users are responsible for retrieving this information and using it to guide plant operation, inspection, and maintenance activities. The benefit of keeping current on GE bulletins and advisories, it was said, saves users money in the long run. It was also mentioned that all owners get an updated O&M manual annually from GE and that it’s important to use the latest version of that material. If you don’t know who in your organization receives the CD from the OEM, contact your customer service rep.

Here’s a run-down on some of the specific engine-related technical issues that were addressed during nine hours of total breakout time. Details will be presented in the 3Q/2012 issue.

No. 3 bearing stationary seal.
Peeling of paint from the engine frame.
Spline adaptor wear.
Variable stator vane (VSV) systems are “off-schedule.”
No. 4B bearing failures.
Oil coking problems.
Combustor issues.

In addition to discussion of engine parts, attendees participated in lively discussions on GT-inlet air filters and water washing. Air filters are an agenda item at virtually every gas-turbine user meeting. The discussion at the LM2500 breakout focused on a performance comparison of prefilters/final filters and HEPA filters. A plant in the LA basin found value in switching to HEPA. A detailed analysis of HEPA filter performance was presented later in the meeting by a representative of Alliance Pipeline. That subject matter is summarized in the first of four short articles that follow this roundup.

Water washing predictably followed filters as a discussion topic. If you’re not joining the “HEPA cures all ills” movement, water washing is necessary to maintain compressor performance. It seemed that everyone in the group had an opinion and wanted to be heard. Opinions were endless—perhaps taking half an hour, so it seemed—on online versus offline washing and which vendor had the most effective soap. Access to such information is one of several good reasons for attending the user group meeting catering to your engine; for GE aeros it would be Western Turbine.

Finally, a representative of Strategic Power Systems Inc (SPS), Charlotte, which has tracked performance metrics for owner/operators of LM engines since the organization was incorporated, addressed the group regarding systems and components adversely impacting reliability.

Attendees were urged to increase the level of attention given to controls, the combustion system (including flame detection), package fire protection, and gas control valves. Sticking of gas control valves is an issue of increasing concern. The subject of parts-life tracking was also mentioned. For more on this subject see Article 2 and the end of this roundup report.

LM5000. The primary concern of owner/operators in this breakout was on-going concern regarding long-term support for the LM5000, no longer in production, from the OEM and depots. The group was told that GE is still supporting this fleet. But no mention was made about how long support might continue. “Where will we be in five years?” was one question asked. The OEM was said to have told at least some owner/operators it would not support maintenance service of third-party reverse-engineered parts.

What to do? Users are asking for a list of available parts; the OEM and depots want information from users. No easy answer to this standoff: Users don’t want to commit to parts they might not need, suppliers don’t want to make parts they might not sell. Perhaps an intermediary—SPS was mentioned—could handle the information exchange to the satisfaction of both sides.

Technical issues discussed included the following:

Stage-0 corrosion in LP compressors.
Torque-value concerns for LPC Stage -3 flange bolts.
LTP stator cracks have been found on high-hours units. Typically, engines are making it through the second major but not to the third.
VSV hardware issues.

LM6000. News item: The one-thousanth LM6000 was shipped in 2011. This is significant considering the first engine in the series was manufactured only about 20 years ago. Today the fleet totals 1015 units—about three-quarters of those equipped with a single annular combustor, remainder with a dry, low-emissions combustion system. Engines in service number 975, those operating stand at 766. Fleet operating hours are up to about 24-million, with the high-time engines (SAC/DLE) north of 130,000/ 120,000 hours.

Interesting audience demographics: By show of hands, as many as two-thirds of the attendees said they were first-timers. More than half the remainder said they had been attending the Western Turbine conference for five years or longer. One early discussion was on the variety of combustors found on LM6000s and the issues that drove design changes. A few users reported that they actually scrapped some new combustor designs and returned to the old.

The OEM presented on controls upgrade options. Users seemed pleased that the presentation defined benefits of upgrading from various control platforms to new ones. At the present time the Mark V will be considered obsolete in 2014, the Mark VI in 2019, and the Mark VIe in 2026.

SPS presented ORAP® data of interest to this group of users. It included mention of top contributors to forced outages and statistics on engine-removal duration and intervals for the past five years. Tom Christensen also spent a few minutes discussing a free tool available to users of its Operational Reliability Analysis Program to facilitate submittal of GADS reports.

Recall that the North American Electric Reliability Corp (NERC) collects event and performance data on gas turbines for its Generating Availability Data System—the same data SPS collects for ORAP. But because the formats for the two databases are different, NERC and SPS created a software program which both companies can use.

There were several presentations by owner/operators during the user-only sessions for the LM6000 track that generated considerable discussion. Two that stand out:

Experiences from first-time engine removals. Half of the attendees had not participated in an engine removal. Think of the insights gained by these users from attending this session: certainly worth the meeting registration fee by itself.

About 10% of those with applicable experience said they had issues removing their engines the first time. Outage preparedness was stressed as critical to success. One user discussed crane issues. His plant required a new crane and had to rent pins and pulleys from the OEM. Cranes are oft forgotten during outage preparation. Chalk that up to a lack of attention to detail in most cases. Remember that cranes, like elevators, must be checked by certified inspectors regularly. Forget this and your outage critical path can be adversely impacted before you get started.

Another participant recommended using dolly skates under the engine container and making sure the concrete padding is sufficient to handle the weight. Get experienced people involved in your first engine removal or be prepared for surprises that inexperience will bring. One incident reported during the session was related to bearing scratches. Owner didn’t think much about them; the depot insisted on replacement, adding to outage duration.

Wiring issues, which contributed to phantom trips of several new units being installed at one site, were traced to poor subcontractor performance. Lessons learned: Contractors have the same difficulties as power producers when it comes to hiring capable people, and owner/operators are responsible for following and checking all work prior to sign-off.

Here are several things that were overlooked on this project: (1) terminal boxes located below the evap cooler were not water-tight and condensation caused shorts; (2) termination boxes were not properly connected (poor wiring practice); (3) some boards were not grounded; (4) wiring in confined spaces was poorly executed. Impact of the poor workmanship was considerable. For example, the evap cooler had to be shut down because plant personnel could not access the board to fix it. Result was each unit being derated by 6 MW.

LMS100. The LMS 100 is quickly gaining in popularity. There are now 26 engines in operation and the fleet has amassed 110,000 operating hours and 17,500 starts; the high-time engine is at 22,000 hours. Only one engine was reported as operating in base-load service; the others are used either for peaking or cycling. Six more engines are in commissioning, three of those in California and the remainder outside the US. Expectation is that fleet size could double in a year.

The session was jump-started with a presentation on Black Hills Corp’s Pueblo Airport Generation Station, equipped with two LM6000PF-powered 2 x 1 combined cycles and two LMS100 peakers, which began service on Jan 1, 2012 (Article 3 at the end of this roundup).

One attendee told the editors he believed the relationship between the OEM and the owner/operators had improved over the last few years and that there was a feeling of cooperation permeating the meeting room. It was not a complaint-driven discussion, he said. The GE portion of the program was particularly informative, the engineer continued, discussing more than a dozen programs aimed at addressing fleet issues. In at least several cases, the OEM and owner/operators were collaborating to develop solutions. CCJ