We are running GE mark vi, our gas turbine has been down for more than one year, we fixed it last week, we run the machine to full speed but the IGV did not, we try forcing the logic from mark VI but there was no respond. We have change the servo coil, still no respond. Please can somebody help me out, your contribution is highly appreciated.

 

@EBUWAODUWA,

Your post really doesn't fit in with the topic of this thread and should be its own thread.

But the fix is probably simple. Most GE-design heavy duty gas turbines use a solenoid-operated valve to allow high-pressure hydraulic oil to get to the IGV electro-hydraulic servo-valve so it can be modulated opened and closed. They are fairly simple devices, and they are prone to get stuck when the oil in the valve gets old and very thick and sticky. You didn't say what Frame size machine you are working but for the majority of non F-class machines the solenoid, device number 20TV-1, is mounted very near the Aux. Hydraulic Pump. It is fairly easy to disassemble and clean using some diesel fuel or WD-40 and make sure the spool piece moves freely before re-installing it.

Usually, when 20TV-1 is de-energized (when the machine is not starting or running or shutting down) there is a small amount of oil flowing out of the bottom of the valve--it seems to be "leaking." And when the solenoid is energized (during starting, running and shutdown) there is no flow of oil out of the bottom of the solenoid valve. You can force the 20TV-1 solenoid logic to energized and de-energize the solenoid when the Aux. L.O. and Aux. Hyd. Oil pumps are running when the machine is shut down and observe the flow of oil coming out of the bottom of the assembly (after re-installing it and before STARTing the machine).

The same thing can happen to the 20FL-1 solenoid valve and/or the 20FG-1 solenoid valve.... so that when fuel should be flowing to the machine during firing there might not be because the solenoid valves are stuck.

Please write back to let us know what you find and how you solve the problem.

In the future when you have a question unless it fits well with an existing thread please start a new thread.

 

Hello,

I have moved the posts to a new thread.

Bertus

 

We are running GE mark vi, our gas turbine has been down for more than one year, we fixed it last week, we run the machine to full speed but the IGV did not, we try forcing the logic from mark VI but there was no respond. We have change the servo coil, still no respond. Please can somebody help me out, your contribution is highly appreciated.

Are you receiving any Diagnostics alarms for the IGV's?

I'm assuming the IGV's are variable?