Common Problems with Hydraulic Actuators in Heavy Duty Gas Turbines

›Hydraulic fluid viscosity dependent on ambient

temperatures – leads to slower response times in

cold temperatures – resulting in failed starts

›Fluid varnishing can lead to clogged servovalve

passages resulting in failed starts or stops

›Potential of high pressure hydraulic leaks pose safety risks

›Premature seal failure – noise on hydraulic control

circuits can lead to premature wear on hydraulic

and gas seals

›No actuator/valve data to predict failure in advance of outages

›Electric actuators are paired with a remote Digital

Valve Positioner (DVP) that controls the actuator

operation and serves as the customer interface for

power/signal wiring and digital communications.

Multiple DVP’s can be packaged within a stainless

steel cabinet and prewired from the factory to greatly

reduce commissioning time