Brayton-cycle machines: they compress atmospheric air, burn fuel in the combustor and expand the hot gases in the power section — for power generation and mechanical drive of large compressors (class GT of ISO 14224:2016; API 616).
Usual types
(handbooks per type in Phase 1)
- Industrial (heavy-duty) — designed for continuous stationary operation: rugged, long intervals, lower simple-cycle efficiency (recovered in combined cycle);
- Aeroderivative — an aero-engine core adapted for ground duty: light, fast start, module-swap maintenance — typical of offshore platforms and grid peaking.
Boundary note: the set's own axial compressor is an integral part of the machine (a subunit), not a process compressor.
Reliability: life is dictated by the hot section (blades and combustors — creep, thermomechanical fatigue, hot corrosion); inlet air filtration and fuel quality are the dominant process variables.