LM2500 Aeroderivative Gas Turbines and its features
Ideal for Marine Applications
Based on the very successful heritage of the LM2500 gas turbine, the 28.6 MWe/40,200 shp LM2500+ has a revised and upgraded compressor section with an added zero stage for increased flow and pressure ratio and revised materials and design in the high-pressure and power turbines
Features & Benefits
The gas generator operates at a compression ratio of 22 to 1. The inlet end of the LM2500+ design is approximately 13 inches (330 mm) longer than the current LM2500, allowing for retrofit with only slight inlet plenum modifications. In addition to the hanging support found on the LM2500, the front frame of the LM2500+ has been modified to provide additional mount link pads on the side. This allows engine mounting on supports in the base skid.
The LM2500+ is offered with two types of power turbines: a six-stage, low speed model, with a nominal speed of 3600 rpm; or a two-stage high speed power turbine (HSPT). The six-stage power turbine displays several subtle improvements over the L2500 model from which it was derived:
- Flow function was increased by nine percent to match that of the high-pressure compressor.
- Stage 1, 5, and 6 blades as well as the stage 1 nozzle were redesigned.
- Disc sizing was increased for all of the stages.
- Spline/shaft torque capability was increased.
- Casing isolation from flow path gases by use of liners stages 1 through 3
The LM2500+ two-stage HSPT has a design speed of 6,100 rpm, with an operating speed range of 3,050 to 6,400 rpm. It is sold for mechanical drive and other applications where continuous shaft output speeds of 6,400 rpm are desirable. When the HSPT is used at 6,100 rpm to drive an electric generator through a speed reduction gear, it provides one of the best options available for power generation applications at 50 Hz.
Both the six-stage and two-stage power turbine options can be operated over a cubic load curve for mechanical drive applications.
Features of the LM2500+ include:
- Direct drive for power generation
- Variable speed for mechanical drive
- Full power in ten minutes
- High thermal efficiency
- Compact, modular design
- 25 percent more power than LM2500
- Easy onsite maintenance
- Dual-fuel capability (distillate or gas)
- Marine Drive Package
In 1998, a version of LM2500+ was introduced to commercial marine application. The only differences between the marine and industrial versions to address the harsher environment are as follows:
- Stage 1 HPT nozzle coating
- Stage1 HPT shroud material and coating
The aeroderivative LM gas turbine packages are particularly well-suited for marine applications due to their compact size, light weight, low SOx and NOx emissions, high power density and lack of sludge and particulates. The LM2500+ has been proven in more than nine million operating hours of marine application. The LM2500+ marine drive package is rated at 26.6 MWe with SFC 207 gram/kWh (liquid fuel, 100/250 mm inlet/exhaust losses, 15 °C, 60 percent relative humidity).
The LM2500+ is also available as a Combined Gas Turbine Steam and Electric System (COGES). High-pressure, superheated steam is produced from exhaust gas, which is used to power the steam turbine generator set. This arrangement increases system thermal efficiency by 10 to 20 percent.