Chapter 1
Turbine Package System Overview
1-20
P2 Blow-Off Valve Air Manifold
Instrument air is supplied to the P2 blow-off valves via the air manifold during engine start and
shutdown. The P2 blow-off valve system is protected from excessive pressure by a pressure relief
valve (PSV159).
P2 air for the P2 blow-off valves is supplied from the engine through a filter (XV187) and
pressure control valve (PCV150) during normal engine operation.
A non-return valve (XV430) prevents P2 air from entering the main instrument air system during
normal engine operation.
Engine Auxiliary Module
Instrument air is supplied via process airlines to the engine auxiliary module for pressurization of
the engine seals and to the instrument air manifold.
Combustion Air Filter System
Instrument air is supplied as required to the combustion air filter for operation of the pulse clean
system (if applicable).
