Hi Pals, hope you're good!

I'm facing LM 2500 power turbine inlet exceeding only at 1 radial position during starting up sequence. As we know that this type of engine dividing the thermocouple on to 8 area. It makes gas temperature spread extremely out of limit, but only 1 area. This impact is severe. After remove the fuel nozzle, found related area fuel nozzle clogged.
Prior this incident, we're fuel-switching from gas to liquid. But there alarm trip from fuel gas supply overheat.

A lot of thank for anything feedback here!

 

Hi Pal

I am doing well thank you for asking , hope all is well

Can you tell us Control system associated to this unit?

Also why Gas fuel supply overheating alarm coming if you operate unit on Liquid fuel?

Are you referring to exhaust spread Temperature?

If so some datas like trends would be welcome here

 

ControlsGuy25,

Happy to hear you're doing well.

This post is pretty muddled (confusing). Power turbine inlet refers to the gas generator section (the axial compressor, annular combustion section and HP turbine) exit temperature that enters the LP turbine section (power turbine) that drives a load (generator or centrifugal compressor or pump, for example).

So what he's probably saying is that the temperature of the hot gases exiting the gas generator (HP turbine) and entering the LP turbine (power turbine) experienced a high exhaust temperature spread of one of eight thermocouples. They removed and inspected fuel nozzles and found the fuel nozzles in the respective area clogged (choked; plugged).

And, apparently this happened during a fuel change-over from heated natural gas to liquid fuel, and because the flow of natural gas was decreasing during the transfer (or was at zero--we don't know based on the information provided) the gas fuel supply overheat alarm was annunciated.

The original poster doesn't say if they've restarted the machine and tested liquid fuel operation (or even gas fuel operation) to see if the spread problem went away.

And the original poster hasn't provided any actionable data--temperatures, including the "normal" power turbine inlet temperature readings at the time of the trip and the outlier temperature.

So, it's really not clear what he's asking us to do.... I mean, liquid fuel nozzles, especially ones in a dual fuel machine, are prone to plugging (choking; blockage). And especially if the machine doesn't run on liquid fuel very often. The liquid fuel in the nozzles can carbonize (harden) and cause plugging, choking, blockage. The original doesn't say why the unit was transferring fuels because of a gas fuel issue, or the transfer was manually initiated by an operator, or how often the fuel transfers occur or how often and for how long the machine runs on liquid fuel.

There's just a LOT the original poster didn't tell us that might have been helpful, but it really isn't clear what kind of help the original poster wants. Based on the information provided, there's not much more we can say.

 

ControlsGuy25,

Happy to hear you're doing well.

This post is pretty muddled (confusing). Power turbine inlet refers to the gas generator section (the axial compressor, annular combustion section and HP turbine) exit temperature that enters the LP turbine section (power turbine) that drives a load (generator or centrifugal compressor or pump, for example).

So what he's probably saying is that the temperature of the hot gases exiting the gas generator (HP turbine) and entering the LP turbine (power turbine) experienced a high exhaust temperature spread of one of eight thermocouples. They removed and inspected fuel nozzles and found the fuel nozzles in the respective area clogged (choked; plugged).

And, apparently this happened during a fuel change-over from heated natural gas to liquid fuel, and because the flow of natural gas was decreasing during the transfer (or was at zero--we don't know based on the information provided) the gas fuel supply overheat alarm was annunciated.

The original poster doesn't say if they've restarted the machine and tested liquid fuel operation (or even gas fuel operation) to see if the spread problem went away.

And the original poster hasn't provided any actionable data--temperatures, including the "normal" power turbine inlet temperature readings at the time of the trip and the outlier temperature.

So, it's really not clear what he's asking us to do.... I mean, liquid fuel nozzles, especially ones in a dual fuel machine, are prone to plugging (choking; blockage). And especially if the machine doesn't run on liquid fuel very often. The liquid fuel in the nozzles can carbonize (harden) and cause plugging, choking, blockage. The original doesn't say why the unit was transferring fuels because of a gas fuel issue, or the transfer was manually initiated by an operator, or how often the fuel transfers occur or how often and for how long the machine runs on liquid fuel.

There's just a LOT the original poster didn't tell us that might have been helpful, but it really isn't clear what kind of help the original poster wants. Based on the information provided, there's not much more we can say.

@WTF?

Thank you for these clarifications ....

Waiting from Original Poster @Sean to provide more details as you well mentionned ..