Front Frame Assembly

The front frame of the LM6000 gas turbine is a major structure that provides support for the low pressure compressor rotor and the forward end of the high pressure compressor rotor through No 1B, No 2R, and No 3R bearings. The frame also form an airflow path between the low pressure compressor and the high pressure compressor inlet. Front engine mount provisions are located on the front frame 3 o’clock and 9 o’clock positions. One pad is included on the frame outer case for mounting high pressure compressor inlet temperature sensors T2.5 and high pressure compressor pressure sensor P2.5. Sensors provide control information to the fuel management system.

Front frame is made from a high-strength stainless steel casting. Twelve equally spaced radial struts are used between the hub and outer case to provide support for the inner hub. Twelve variable-position bypass valve doors are located on the outer wall for the low pressure compressor discharge bleed.

The front frame contains the engine A-sump, which includes a thrust bearing (1B) and roller bearing (2R) that support the low pressure compressor rotor, and a roller bearing (3R) that support the forward end of the high pressure compressor rotor. Lubrication oil supply and scavenge lines for the A-sump are routed inside the frame struts. The inlet gear box is located in the A-sump with the radial drive shaft extending outward through the strut located at the 6 o’clock position.