Starting means turbine shaft fail to break turbine away

Very interesting topic..

I have got many points from experience you shared. We do have suffered that problem twice on our machine.and alarm turbine shaft failed to break away was also received. Controlman and Salman points are exactly that were faced

Once it was due to Generator lift oil discharge pressure low, and second time it was due to Lube oil console level low switch in actuated state. in both cases Machine will not come on Turning Gear.

Thanks
 
Dear all

We have experienced the same problem with G.E ms9001 E (frame 9) turbine where the problem once was due to the starting means filter restricting pressure build up for the torque converter. the other was the generator jacking oil filters found dirty. again restricting sufficient pressure for jacking the the generator bearing 1 and 2.

It is also advised to test the lube oil for its viscosity.

we once tried to increase the angle of torque converter motor to 75% just to provide initial torque manually as the turbine turned bought the control of 88 tm back to auto position.

Best Regards
suhail
 
I am currently experiencing this in my plant. it is a GE Frame 9E turbine. The unit was on grid and there was system disturbance which made it to trip. It was unable to attain the cooldown mode. Efforts to put it on cooldown proved abortive as the alarm; starting means device failed to breakaway L45CR_Alm. At first, we thought it was the jacking oil pump 88QB but it wasn't. Meanwhile the wheelspace temperature is about 55deg.
Right now, we are suspecting the torque converter,which is at 67.9deg opening.

What must have been the cause of this failure to breakaway that is inhibiting the cooldown mode operation please?
 
Based on the (minimal) information provided, it's impossible to make even an educated guess about what the cause might have need. The previous replies to this thread and many other similar threads on control.com contain a lot of possible causes, but because you have chosen not to share any specific information about the turbine (type of cooldown mechanism (slowroll; turning gear; ratchet; etc.)) or tell us how long the unit was at zero speed before you could try to put it on cooldown there's really no way to answer your question.

Lastly, contrary to wildly popular and false belief every GE-design Frame 9E heavy duty gas turbine is not identical to every other GE-design Frame 9E heavy duty gas turbine. Many different packages, auxiliaries and combustion systems have been supplied over the decades the machines have been produced.
 
We are using 6 Units Frame 9E gas turbines and we often have the problem with failure to break away.

Up to now, most of the time, we have experienced problem with starting means filter blockage. Now we started to replace the filter after each outage as a preventive measure, the problem rarely happens.
Other than the starting means filter, we experienced the problem with Torque converter, which is not giving sufficient torque to break away with the reference angle from the controller. The main MCC of the torque converter have option to raise the angle manually, we could solve the problem adjusting manually to get rid of shaft failure to break way issue.

There were some coinsurance, we have changed total torque converter, due to malfunctioning of the equipment.

Only one or two times in the entire history, we had problem with 20TU solenoid, which dumps the oil from torque converter. The solenoid is provided with a limit switch also.

As you mentioned, you have pressure measurement on the torque converter inlet, it will definitely help you to find out where the problem lies. If everything in torque converter is clear, then we need to suspect the jacking oil pressure. I believe, there is are pressure switches installed to tell the system if jacking oil pressure is low for both the generator bearings. (L63QBL in our case) Or, as by measuring the lift by Bentley probe or by fixing a dial gauge. If the lift is less, the relief valve in the system can be adjusted to make it okay. However, this will be done with help of mechanical, who tells you how much lift is required on each bearings.
Hi boos
we have 2 like this turbine model and the we are facing like this problem .my question is if the pressure inside the torque converter is 17 bar is that possibles we check or replace the filter?
 
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