By Brian K. Schimmoller,
Between 1999 and 2004, hundreds of gas turbines will have entered commercial service in the power generation market. Most of these will be advanced combustion turbines – with high firing temperatures, complex combustion systems, intricate cooling mechanisms, advanced coatings, and expensive hot gas path turbine components. For the turbine owners to realize the short-term and long-term economic paybacks promised in the pro forma documents, maintaining these units at optimal performance levels will be essential. The combustion turbine OEMs represent one certain source for qualified aftermarket service and maintenance, but third-party organizations are emerging as well to capitalize on this growing market.
Power Engineering recently had the opportunity to meet with the principals involved in one such company, Turbine Fleet Management, an alliance between Duke/Fluor Daniel and Liburdi Engineering that will leverage Strategic Power Systems’ ORAP monitoring and reporting capabilities and Fluor Global Services’ staffing and crafts management expertise. The new organization’s goal is to integrate information, engineering, maintenance, repairs and operations across fleets of combustion turbines. Similar collaborative ventures are likely to emerge to vie with the OEMs; Sermatech and Wood Group, for example, are reportedly expanding their capabilities to service advanced gas turbine models.
“The energy market is pushing turbine owners to look for ways to drive down costs and increase the profitability of their CTs,” said Ted Rosiak, president and CEO of Turbine Fleet Management (TFM). “By focusing on our clients’ business drivers, not our own, we can tailor a program that maximizes the value of the client’s assets.”
A number of plant developers are assembling turbine fleets that are, for the most part, homogeneous, based on the same model of gas turbine, whether it’s the GE 7FA, the Siemens 501F, the Mitsubishi M501F/701F, or the Alstom GT24/26. “When you look at how you need to maintain these fleets, it only makes sense to maintain them as a fleet instead of as separate generating units,” said Ray Olson, chief operating officer of TFM. “Our definition of turbine fleet management is maximizing the performance and output of one or more generating plants while optimizing the service life of the generating equipment.” Olson identifies more than 440 GW of gas-fired generation in areas around the world that would benefit from TFM’s ability to offer a full-scope of LTSA-like services. That translates into about $1 billion annually. The market will be fiercely competitive, and although the OEMs will likely retain a large share of the business, opportunities will emerge for third parties as competitive pressures force plant owners to achieve additional cost savings.
The high-tech nature of the newer combustion turbines complicates the picture for owners considering various service options. For example, many people in the industry believe there are very few service options for the advanced F-class turbines. “There are two philosophical extremes,” said Joe Liburdi, president of Liburdi Engineering. “One extreme is that only the OEMs can provide this type of service. The other extreme is that groups that have been doing gas turbine repairs will be able to simply transition to tackling the more advanced work. Neither position is correct.” Whether it’s an OEM or a third party, the service provider must offer an experienced combination of metallurgical and mechanical engineering skills.
The long-term service agreements, or contractual service agreements, offered by combustion turbine OEMs are designed to deal with some of these technology issues by providing access to parts, access to the expertise of the OEM, and access to extensive operating and maintenance histories. LTSAs are effective risk mitigation tools in certain instances, but some believe that they sell the owner short. “The reality is that the LTSA or CSA is put in place to mitigate the uncertainty for the uninformed client or operator,” said Sal DellaVilla, president of Strategic Power Systems. “Advanced technology has created some issues with respect to parts life and life limitations in terms of repair capabilities. The bottom line, in our view, is to build an informed client so that they understand parts life, empirically, as well as theoretically.”
Data is essential to developing the framework that can provide an integrated analysis of a given turbine fleet. The TFM approach is built around Strategic Power Systems’ family of ORAP (Operational Reliability Analysis Program) products, which will collect and integrate all operating and engineering data, interface with unit-level controls and plant DCS systems, and track parts condition information recorded by field personnel during maintenance events. Extensive data is also obtained from Liburdi Engineering’s WinGTAP program, which provides detailed performance analysis of the gas turbine, and from metallurgical data Liburdi collects to assess parts life.
Downstream data integration and analysis then permits decisions to be made regarding inventory management, parts repair/replacement, unit upgrades, annual maintenance planning, operational changes, etc. “The technologies and capabilities that we’re bringing to the table are not earth shaking,” said Olson. “Everyone in the industry is doing this to some degree. The differentiator is the integrated approach and doing your homework. There’s no reason to collect data for data’s sake. Our intent is to collect operational data and generate additional engineering data and metallurgical data and use that data to drive all of our downstream activities, including maintenance, warehousing and marketing. What we’re advocating is not simply doing major maintenance activities by the book, but customizing those maintenance activities to suit the operating environment and the operating cycles of that particular plant.”
Watson Cogen, a 420 MW facility in Los Angeles that relies on four 7EA turbines, provides an example of the benefits that can be realized by integrating operating, mechanical and metallurgical data with engineering analysis. “Metallurgical analysis showed that there was capability to extend the life of the first-stage buckets and rejuvenate them using full-life repairs,” said Liburdi. “This involved stripping the buckets completely, applying a better coating, both internally and externally, and conducting complete HIP rejuvenation processes that restored the component to a like-new condition. When we put these parts back in service, we monitored them every 24,000 hours. Those same buckets have now completed 100,000 hours and are still operating reliably. Most of the rest of the fleet has retired their first-stage buckets long before 50,000 hours. The technology and quality control has saved the operator millions of dollars.”
As CTs have become the engine of choice for new generation, the resources required for manufacturing, construction, installation, testing, and maintenance has created a big drain on the labor pool. “This drain has been particularly acute for what is called centerline work” said Tommy Thompson, senior director with Fluor Global Services. “This is the nuts and bolts work on the turbine itself – installing the turbine, taking it apart, putting it back together. As a response to this craft issue, we have had to take existing training programs and upgrade them. We’re taking people who have basic millwright skills and some turbine skills, adding to those skills, and certifying the capability of the individual to deliver those skills as part of the overall program. Training is both internet-based and hands-on.”
The gas turbine service market is poised for tremendous growth, lagging by a few years the construction and commissioning boom of the huge CT fleet. Various options are available – and still emerging – for turbine owners to manage their maintenance and service needs. No one solution will meet every fleet owner’s preferred mix of price, risk mitigation, and technical expertise, which only means that the service options will continue to evolve in response to changing market conditions.