This is for all GE LM2500 Turbine users for people like in operations,
maintenance. Please share your experience,knowledge and stories about your
time around LM2500 Gas Turbines...

Sailing on the USS Donald had two LM2500s used for propulsion. It was a pain to access and calibrate the VSV, IGV, and VBVs.

Take heart, the access to the VSVs and IGVs on the industrial LM2500s is much easier. Also the marine versions have a fuel control on the aft left hand side (ALF) of the AGB. The industrial turbines have a VSV control on the fwd R/H side of the AGB that is much easier to adjust.

I dont believe that the LM2500 has VBVs. Only the LM6000 and LM5000 have this arrangement since there is a Low Pressure Compressor forward of the HPC. During startup some of this compressed air is vented to atmosphere until the engine increases in power. This LPC acts similar to a supercharger.

The marine turbine enclosure is also so compact and tight it makes maintenance tasks inside the "box" difficult.

Good luck, and when you get out of the Navy there are lots of jobs in the cogeneration industry, IPP (Independent Power Producers), utility, etc. They are screaming for GSEs and GSMs.

Jack Kelly
(former GE Field Service Rep)
(former USN MM3)

spent 4 years of 9 of my navy career at a shore facility changing out LM2500 gas turbines, the worst part of the job was when we would have to roll the compressor while in the module.and having to rebould the vsv bushings stages 1-6 all of them from the inside out.

Replacing VSV bushings is definitely a pain. Your hands look like you put them in a veg-o-matic after you get done.

Quite some time ago southern CA has a cold snap and quite a few engines had ice damage. GE did not have enough lease engines so I remember doing about 6 engines in a row replacing Stg 1 through 16 blades and vanes in the compressors. We did quite a bit of hand blending, had to do blade balance in the field on each stage of rotor blades.

The LM6000 has what is called a "high boss case" Stages 3, 4, and 5 VSVs have a square block bolted to the compressor casing that allow you to remove the boss with the vane. Then the inner and outer bushings can be replaced and the assembley put back into position. This is sweet.

Of course the VSV lever arms, actuators, rings, etc. must all be removed from the outside of the compressor casing, but it eliminates opening up the compressor. Generally on the LM5000 and LM6000 GE has had excessive wear on these later stages so that is why they developed the high boss case for the LM6000.

Not for the LM2500 and definitely not the LM5000 since it was going out of production and being replaced by the LM6000.

I take that back on removing the entire VSV actuator rings, and VSV lever arms. The majority of the VSVs on the LM6000 can be replaced without removal of the rings, however if vanes require bushing that are in the area of 3:00 and/or 9:00 where the VSV actuator ring half bridge connectors are located these will be required to be removed.