gas turbine GT 6F.03

How long can a gas turbine run without electrical load? (without generator synchronization system)
Well I would say that its up to you man!

The question I return to you is :
How long would you want to spend/waste money by operating GT without synchronized to a grid (whatever it is small or infinite)....

We do not know about your plant configuration ( Steam process .., auxiliary steam for any process purposes...or not)

I would say that runing a GT without any purposes is not recommeded at all.


James
 
Merabiko8,

Actually, the answer depends on a lot of issues--the biggest of which is the type of combustion system. If the unit has conventional combustors (diffusion flame combustors)--which includes MNQC combustors (Multi-Nozzle Quiet Combustors) it can probably run for a couple of hours without any problems, maybe more. However, if the unit has DLN combustors, particularly DLN-I combustors, then it probably would NOT be a good idea to run it for more than an hour or so (because of the heat of the diffusion flame, the low IGV angle).

If the gas turbine exhausts into an HRSG (Heat Recovery Steam Generator), that may have an effect on the total running time. If the HRSG has auxiliary duct burners (auxiliary firing) it would probably NOT be advisable to try to run them without load, and with the IGVs not fully open. (That doesn't mean you can "force" the IGVs open to bypass that--that is NOT acceptable, ever.)

You might find some OEM (Original Equipment Manufacturer) information in a GE publication, GER-3620 (I believe that's the publication number). It's kind of difficult to read because it tries to cover every possibility for just about every frame size machine is as few words as possible. But, it's probably the best document for this kind of information (and any other operating information, as well). I don't have a copy to send to anyone; use your preferred World Wide Web search engine to find a copy. (I think Revision R is the latest, but I'm not even sure about that anymore.)

If you absolutely have to run the unit without any load, please watch the wheelspace temperatures closely, and if they start rising, and rising quickly, that's not a good sign. And, also depending on the combustion system and the programming in the Mark*, the compressor bleed valves might not be closed at FSNL with no load. So, that means the unit is going to be very inefficient (burn more fuel than even at very light load with the compressor bleed valves closed), and the internal cooling might also be adversely affected. AND, pay attention to vibration! If it starts to increase on either bearing, and starts to increase quickly, it would be best to shut the unit down.

Hope this helps! Best of luck!
 
Merabiko8,

Actually, the answer depends on a lot of issues--the biggest of which is the type of combustion system. If the unit has conventional combustors (diffusion flame combustors)--which includes MNQC combustors (Multi-Nozzle Quiet Combustors) it can probably run for a couple of hours without any problems, maybe more. However, if the unit has DLN combustors, particularly DLN-I combustors, then it probably would NOT be a good idea to run it for more than an hour or so (because of the heat of the diffusion flame, the low IGV angle).

If the gas turbine exhausts into an HRSG (Heat Recovery Steam Generator), that may have an effect on the total running time. If the HRSG has auxiliary duct burners (auxiliary firing) it would probably NOT be advisable to try to run them without load, and with the IGVs not fully open. (That doesn't mean you can "force" the IGVs open to bypass that--that is NOT acceptable, ever.)

You might find some OEM (Original Equipment Manufacturer) information in a GE publication, GER-3620 (I believe that's the publication number). It's kind of difficult to read because it tries to cover every possibility for just about every frame size machine is as few words as possible. But, it's probably the best document for this kind of information (and any other operating information, as well). I don't have a copy to send to anyone; use your preferred World Wide Web search engine to find a copy. (I think Revision R is the latest, but I'm not even sure about that anymore.)

If you absolutely have to run the unit without any load, please watch the wheelspace temperatures closely, and if they start rising, and rising quickly, that's not a good sign. And, also depending on the combustion system and the programming in the Mark*, the compressor bleed valves might not be closed at FSNL with no load. So, that means the unit is going to be very inefficient (burn more fuel than even at very light load with the compressor bleed valves closed), and the internal cooling might also be adversely affected. AND, pay attention to vibration! If it starts to increase on either bearing, and starts to increase quickly, it would be best to shut the unit down.

Hope this helps! Best of luck!
 
However, if the unit has DLN combustors, particularly DLN-I combustors, then it probably would NOT be a good idea to run it for more than an hour or so (because of the heat of the diffusion flame, the low IGV angle).
GT 6FA.03 Dokument-
Combustion system
1.5.1. General
The dry low NOx 2.6 (DLN 2.6) control system regulates the distribution of fuel delivered to a multi-nozzle, total premix combustor arrangement. The fuel flow distribution to each combustion chamber fuel nozzle assembly is calculated to maintain unit load and fuel split for optimal turbine emissions. The combustion system is of the reverse-flow type with the 6 combustion chambers arranged around the periphery of the compressor discharge casing. Combustion chambers are numbered counterclockwise when viewed looking downstream and starting from the top of the machine. This system also includes the fuel nozzles, a spark plug ignition system, flame detectors, and crossfire tubes. Hot gases, generated from burning fuel in the combustion chambers, flow through the impingement cooled transition pieces to the turbine. High pressure air from the compressor discharge is directed around the transition pieces. Some of the air enters the holes in the impingement sleeve to cool the transition pieces and flows into the flow sleeve. The rest enters the annulus between the flow sleeve and the combustion liner through holes in the downstream end of the flow sleeve. This air enters the combustion zone through metering holes for proper fuel combustion and through slots to cool the combustion liner. Fuel is supplied to each combustion chamber through six nozzles designed to disperse and mix the fuel with the proper amount of combustion air.
I wonder your answer, is it recommended to work with this system for an hour or more?
Thank you very much for answering and helping me.
 
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