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Frank Avery, President, Wood Group GTS Power Plant Services, discusses aftermarket support and OEM versus non-OEM parts

Tell us about the company

Wood Group GTS provides support for gas turbines owners including; operations & maintenance (O&M), outage management, as well as optimization and upgrade services. With over 20,000 MW under contract, Wood Group GTS has experience in gas turbine systems and the working environment for critical hot gas path and combustion components.

We have been designing and manufacturing hot gas path parts for over 20 years, using intelligence gained from service experience to implement design modifications aimed at performance enhancement and improved life cycle costs.

The company provides services across the component life cycle, including new parts, technical support, installation and commissioning, routine inspection and high technology repair services. We also offer extended warranties and reduced capital cost.

What are some best practices concerning non-OEM parts?

The best suppliers offer support service to make transition from the OEM smooth and risk free. Owners and operators of gas turbines should ask if potential suppliers can provide engineering support and experienced field technical advisors to supervise installation.


If there is an issue with capital parts, check that the supplier keeps enough inventory to ensure outage windows are met. Operators should also look for competence in systems engineering and design.

When should users stick to OEM parts?

If an owner has equipment still under OEM warranty, electing to use non-OEM parts may have a direct impact on the terms of their warranty agreement. Hence consideration needs to be given to the implications of this decision.

Most mature equipment, on the other hand, is well serviced by the independent network, with plenty of knowledge and experience to support operators moving away from the OEM. Advanced technology gas turbines often require additional support services and are best served by the more established independent providers.

Over time the third party market has developed a solution for replacement turbine components, and in many cases, with parts that last longer and offer lower maintenance costs. Not only can parts’ cost be reduced and warranty coverage increased, but operators often gain additional performance in output, heat rate, and environmental compliance without increasing operational risk.

How is the market developing for F-class parts?

As the market in the Americas turns more towards natural gas, and coal generation facilities are retired, the 7FA gas turbine market will see significantly higher run times, resulting in increased demand for gas turbine parts. This additional run time will allow owners and operators to generate incremental profits, provided that they can reduce the cost of major maintenance through efficient use of the gas turbine parts.

Following a two-major-inspection long term maintenance agreement (LTSA) on a 7FA gas turbine, the operator may be forced to purchase a substantial level of inventory to replenish the installed parts included as part of the initial capital cost.

Many OEM LTSAs are structured so that title to the remaining life of the additional parts purchased during the term of the agreement will revert to the OEM, leaving the facility with a substantial capital cost in preparation for the next two major inspection cycles for these units. Wood Group GTS has developed a solution to address current costs as well as the cost of capital in today’s difficult credit markets.

What is your customer strategy?

This market demands more service beyond parts provision including plant operations and maintenance, term maintenance agreements, as well as optimization and upgrade services. Wood Group GTS elected to partner with Pratt & Whitney Power Systems to service the 7FA market.

This alignment brings together two service and technology companies with complementary capabilities, delivering a maintenance solution focused on lifecycle cost reduction.

A notable win in this market is a multi-million-dollar operations & maintenance and term service agreement with Associated Electric Cooperative (Dell Power). We support other F-class machines, offering a combination of maintenance, repair, optimization and upgrade services, and is well positioned to take advantage of further opportunities as this market develops.