GE upgrades power module for higher output in oil and gas applications
New PGT25+G4 available in late 2006
GE’s oil and gas business has developed a two-stage, high-speed power turbine module to be coupled with the enhanced LM2500+G4 gas generator recently introduced by GE Energy’s aeroderivative business.
The new oil and gas product, named PGT25+G4, will be available for shipment in late 2006, GE reported at the 34th Turbomachinery Symposium. An upgrade of GE’s PGT25+ technology, it is specifically designed for applications across the oil and gas industry including large pipelines, and onshore and offshore production facilities.
The two-stage turbine module is designed to achieve efficiencies greater than 40%, the highest thermal efficiency level available in this power range. Operating at a speed of 6100 rpm, the power turbine is capable of directly driving a compressor without the need of a gear in most oil and gas applications.
At ISO conditions, the PGT25+G4 offers an output of 34 MW, a 10% increase over the existing PGT25+. It also provides a significant increase in power output at high ambient temperatures. For example, at 120° F, the power increase is 20%.
“This upgraded product offers greater availability and gas flexibility for upstream applications,” said Claudi Santiago, president of GE’s oil and gas business. “With its greater output, it provides a better dollars-to-kilowatt ratio than other machines in its class.”
The LM2500+G4 (pictured) is a fourth generation LM2500 and combines an enhanced aeroderitative gas generator with a two-stage, High Speed Power Turbine (HSPT). The first unit is scheduled for delivery in late 2006.
The primary components in the new package have been validated by the extensive experience achieved by GE’s existing products in the PGT family. The package design and footprint for the new machine is the same as the present PGT25+, with one significant change. In the dry low emissions (DLE) version, the fuel gas control features five valves instead of three, enabling more accurate combustion tuning.
Similar to the PGT25+, the new machine offers the flexibility to operate on a range of fuels including natural gas, various gas mixtures, and liquid fuel.
The PGT25+G4 program, conducted at GE’s oil and gas facilities in Florence and Massa, Italy, has included the development and validation of the gas turbine subassembly (the core plus the high-speed power turbine), inlet and exhaust systems, and engine control system.
As part of the new product offering, GE’s oil and gas business will provide a technical services package including customizations to meet specific customer requirements and installation services for difficult environments such as offshore platforms.•
The LM2500+G4 (pictured) is a fourth generation LM2500 and combines an enhanced aeroderitative gas generator with a two-stage, High Speed Power Turbine (HSPT). The first unit is scheduled for delivery in late 2006.
Key features
• +20% power @ 120°F
• IGV redesign to increase flow
• HPC/HPT and TMF life analysis
• DLE emission improvements to maintain 25 ppm
• Increased HPT flow function
• Dry Low Emission (DLE) technology
• Increased flow function
• Strengthened blade material from IN738 to GTD IIIDS
• Availability and gas flexibility in upstream applications
Design information
• 17-stage axial compressor; pressure ratio 21.5:1
• Annular combustion chamber (30 fuel nozzles)
• Two-stage gas generator turbine
• Two-stage high speed power turbine (6,100 RPM)
• Gas generator, power turbine, and auxiliary system are mounted on a single base plate
• Integrated enclosure and base plate for easy maintenance
• Standard configuration: 21 by 12 by 13 ft (6.5 by 3.6 by 3.9 m); weighs 38 tons
