Frame 6, Mark V Failed to Start Up on Distillate

R

Thread Starter

Reoji

Hello all,

We tried to start our gas turbine on distillate today but failed. For info it is not known when the last time the unit operated on distillate. We had a lot of problem, some signal was not getting through and liquid fuel stop valve was not opening. After few replacement of parts with no success we tried to change over to distillate from gas since start up showed no progress. We manage to get the Liquid fuel stop valve (HMI shown as SV after FSR1) to open but the FSR1 % won't increase and ended up tripping the unit on combustion trouble.

Change over was done at FSNL. FSR2 was at 26.47% with FSCR at 25% and FSC at 27% while P2 at 14.27 bar.

we did bleed the fuel for at least 10 minutes and check all liquid pressure to be normal or above 3 bar.

any help would be greatly appreciated,
 
You say it was a long time ago since this machine ran on distillate and you've had a failure of 20FL. Firstly I reckon that your Liquid Fuel system needs a complete check over, probably at stand still if possible (Fuel control valve, Flow Divider & Speed Pickups, LP & HP filters, check valves), but mainly you need to have a look at the logic and see why Liquid FSR is not increasing. Run some plots of what you see after that when trying to run and get back to us.
 
Hi, We can't help you unless you provide <b>ALL</b> the Process- and Diagnostic Alarms that are present before the START or fuel transfer AND during the transfer before and after the trip.

The most likely cause are failed/faulty check valves--both liquid fuel and purge air check valves. (Some newer machines use special three-way valves in place of the two check valves--but the function is the same.

You also need to monitor fuel pressures at the discharge of the liquid fuel flow divider, and monitor the Tell-Tale Leak-off for evidence of leakage.

If you've purged the air (and it sounds like you have) that shouldn't be the problem. But there should be alarms to alert the operators to some issue which might be helpful in resolving the issue..

Lastly, the OEM (Original Equipment Manufacturer) has recommendations for weekly fuel transfers to ensure proper operation of the system and components. If that's not adhered to, then the systems can't be expected to operate as required when required. No exercise; no work. It's as simple as that. Periodic operation is essential to proper operation.

Please write back to let us know what you discover.
 
Dear Reoji

I hope those information helpful for you. 1st thing to do is investigate and check the functionality of stop valve (VS1) by energize the following motors on (88QA, 88HQ) and do forcing to the next signals (L4_xtp >0, L20fl1x >1, L20tv1x >1). Be sure the signal L33fl1c swap to 0. If not, then you should check the fuses of these solenoids in MKV. Also check the resistant of them. It should be about 100-200 ohm. Another things that need to be check are the jumpers of those solenoid at the terminal board.

please feedback me and don't be hesitate.

regards
IGVMAN
 
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