EXPLOTION OF TORQUE CONVERTER

What could be reason for a torque converter of frame 9 machine on baesload suddenly explode and burst in flame. There was an alarm of 0 Q 1087 ALM LUBE OIL TANK HIGH LEVEL when oil was not added to the machine and the oil level was normal. then 1 L33TC SOE Starting Means Torque Converter Unloading Valve. Then, it alarms came several times before the explosion.
 
Well first question is why you did not take action (preventive actions) when that L33TC Alarm /trip came..
( I don have check yet the file that i got on such unit...but I will check on what i got to add comment)

Any work /modification have been done recently on this unit ? if so can you tell us what kind of work..
 
Well first question is why you did not take action (preventive actions) when that L33TC Alarm /trip came..
( I don have check yet the file that i got on such unit...but I will check on what i got to add comment)

Any work /modification have been done recently on this unit ? if so can you tell us what kind of work..
There was no work or modification on the unit and the L33TC came as an SOE and it appeared several times in few seconds.
 
I do not see The L33TC on the Mark 6e app code & Alarm/trip troublesshooting file that I got ..( it in fact a Frame 9FA )
What type of frame unit is ? Frame 9E/FA/FB...
 
Looks like you will need to investigate on what can be source of the SOE during this last Event/operation ...

I would be glad to advise /support BUT I dont have that SOE shown /described on the documents that i got ..

What did the staff do when that SOE came out? Any investigation on kind of limit switch of the Torque converter ....I know that sometimes it can be source of trouble...
 
A slight guess here, but L33TC is probably a limit switch sensing the status of 20TU-1, which is usually a solenoid-operated valve on a Voith-made torque converter which is usually what's used on GE Frame 9E turbines. On this type of torque converter the output shaft is usually always spinning (because it's directly coupled to the input shaft of the Accessory Gear Box--no "clucth"), so it's spinning all the time whenever the turbine shaft is spinning. So, Lube Oil (for cooling and lubrication) is required at all times when the turbine shaft is spinning. The P&ID should show that oil from the L.O. system (Aux. L.O. Pump and/or Main L.O. Pump) is being supplied to the torque converter for lubrication.

20TU-1 is usually energized to "pressurize" the torque converter so that it will transmit torque from the cranking motor to the turbine shaft during starting and up to about 60% speed (usually), when 20TU-1 is de-energized to "de-pressurize" the torque converter to stop the transmission of torque from the cranking motor to the turbine shaft. And, 20TU-1 should remain de-energized until the next time the turbine is started--and it should be de-energized when the unit is at Base Load. BUT, Lube Oil is still required for cooling and lubrication of the torque converter even when the cranking motor is not running--any time the turbine shaft is turning.

The question which hasn't been asked (or answered) is: Why was L33TC changing state when the unit was at Base Load? L33TC is not a Process Alarm; it is a SOE (Sequence of Events) event that is set using ToolboxST to indicate a change of state of the input from the limit switch 33TC. We don't know how the 33TC input was configured or wired, so we can't say if it should be a logic "1" when 20TU-1 is energized or de-energized (in other words, when the torque converter should be transmitting torque or not). In any case, it's pretty clear that L33TC should not be changing state when the unit is at Base Load. If the Mark VIe was toggling the output to 20TU-1 when the unit was a Base Load, well then there was probably Diagnostic Alarm(s) to warn about that, and if the output was being forced when the unit was at Base Load, well, that's probably a big no-no.

What's clear here is that to do a proper analysis of the situation it would be necessary to have the Alarm List (Process Alarms; Diagnostic Alarms; SOEs; EVENTs) for some time prior to the explotion and fire and for some time after the explotion and fire. If there were logic signals which were forced prior to the explotion and fire then that would need to be known also. And if 20TU-1 was being forced prior to the explotion and fire that would need to be explained.

But, the explotion and fire was likely caused by lack of L.O. (for cooling and lubrication purposes) to the torque converter. We can't say too much more than that. There is usually a large strainer on the L.O. supply to the torque converter and if it were really dirty, that might cause a reduction in flow to the torque converter--but without being able to see the app code running in the Mark VIe it's not possible to say what might have caused L33TC to toggle, though it's unlikely it was the Mark VIe causing the toggling unless someone was forcing the logic signal for 20TU-1, or there were serious issues with the Mark VIe--which would be accompanied with Diagnostic Alarms. And, since most sites generally ignore Diagonostic Alarms (at their own peril) and even prevent them from being displayed on the Alarm Window, Diagnostic Alarm information will probably be difficult or impossible to obtain, unfortunately.

Again, lack of L.O. for cooling and lubrication probably caused the explotion and fire. And without more information--lots more--that's about all that can be said about this sad, unfortunate incident. Find out why Lube Oil flow to the torque converter was interrupted while the unit was operating at Base Load and you will have your answer. (What you will probably learn in the root cause analysis of this sad, unfortunate event is that if 20TU-1 were energized while the cranking motor was not running but the turbine shaft was at approximately 3000 RPM that bad things are likely to happen inside the torque converter, causing it to overheat and maybe even explode (that's kind of really hard to imagine, because that torque converter casing has to be VERY strong to transmit torque from the torque converter to the turbine shaft during starting). Anyway, details would be great to know when the root cause is identified.
 
What could be reason for a torque converter of frame 9 machine on baesload suddenly explode and burst in flame. There was an alarm of 0 Q 1087 ALM LUBE OIL TANK HIGH LEVEL when oil was not added to the machine and the oil level was normal. then 1 L33TC SOE Starting Means Torque Converter Unloading Valve. Then, it alarms came several times before the explosion.
Any update on the issue that you described here ....
 
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