CFM56-7B WTT Meeting - September,26-27/2002 CFM / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 1 AFT Sump Inlet Cover O-Ring Turbine Rear Frame Module CFM / Boeing Proprietary Information - Unauthorized Disclosure, Use, CFM56-7B WTT Meeting - September,26-27/2002 or Export are Prohibited Oil Inlet cover O-ring Background 7 reported cases of Oil seepage from the Aft sump (as of July 2002). Affected engines range from 3400 to 9600 Hrs 2300 to 4000 Cy Problem noticed through either Oil Consumption up-shift (3 cases) OR External oil seepage / oily T/R blanket (stable Oil Consumption) AFT loooking FWD Leak path O-ring Turbine Rear Frame Module CFM56-7B WTT Meeting - September,26-27/2002 CFM / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 3 Root cause investigation • Root cause identified damaged Oil Inlet Cover O-Ring • O-ring found brittle, hardened, with compression set and missing material. • O-ring material (Viton E) properties affected due to local high temperature. O-Ring : P/N 649-393-271-0 (IPC 72-00-00-70 Item 320) Oil Inlet cover O-ring Turbine Rear Frame Module CFM56-7B WTT Meeting - September,26-27/2002 CFM / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 4 Additional Findings • Other cause identified with same symptom cracked scavenge brazed nipple (Nbr 5 Brg Support) (Qty: 3). – due to b-nut torque applied w/o counter-torque – require engine change Field containment Plan • On-Wing o-ring replacement procedure to be introduced in the AMM. • Procedure available at Boeing by End of October, 2002 • ESM procedure available. Final Fix • Potential Material change under evaluation Oil Inlet cover O-ring Turbine Rear Frame Module作者: TINA59 时间: 2011-5-16 13:56:34
