标题: CFM High Temperature Oil Issues [打印本页] 作者: 航空 时间: 2011-4-15 19:24:13 标题: CFM High Temperature Oil Issues
作者: 航空 时间: 2011-4-15 19:24:25
February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 1 High Temperature Oil Issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 2 SFH Gasket Seal High Temperature Oil Issues CFM 56 OIL EXPERIENCE (MOBIL JET OIL 291 ISSUE) - Main O/F heat exchanger gasket seal - Other issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 3 Experience with Standard (STD) Grade oils (MJO 2, EXXON 2380…) : Engine sump always remains free of oil coking Coke build up reported inside the aft sump oil supply and scavenge lines – WPG recommendation in place to clean the affected lines at each shop visit opportunity AFT Sump Oil Lines Must Be Cleaned at Each Shop Visit Exposure Oil Experience High Temperature Oil Issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 4 Experience with High Thermal Stability (HTS) Oils (MJO 254, MJO 291, BPTO 2197) : Mobil MJO 254 has been in service for years now with no problem reported Mobil MJO 291 was approved for CFM 56 in Oct. 2000 after service evaluation was conducted on two CFM56 -5B4/2P engines: – These engines had accumulated 3000 H / 2250 C with MJO 291 – All oil wetted parts were found very clean – Aft sump oil supply and scavenge lines found with a thin coke deposit (no significant coke build-up) – All inspected elastomeric and carbon seals were found in good condition – Oil analysis monitoring performed: no change in viscosity and TAN Oil Experience HTS Oils Have Been Developed to Reduce Coking in Engine Oil Systems High Temperature Oil Issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 5 Experience with High Thermal Stability (HTS) Oils (MJO 254, MJO 291, BPTO 2197): Air BPTO 2197 (former EXXON 2197) was approved for CFM 56 in Oct 2000 after service evaluation was conducted : – Two CFM 56 -3 engines were disassembled and inspected All oil wetted parts were found very clean Aft sump oil supply and scavenge lines found with a light varnish of coke deposit (no significant coke build-up) All inspected elastomeric and carbon seals were found in good condition Oil analysis monitoring performed : no change in viscosity and TAN Oil Experience HTS Oils Have Been Developed to Reduce Coking in Engine Oil Systems High Temperature Oil Issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 6 Background • Since early 2001, a total of 25 cases of oil leaks have been reported on CFM 56-5A and CFM 56-5B engines operating with MJO 291 Oil leaks leading to D&Cs 11 cases on CFM56-5B (affected engines had accumulated approximately 3000 H with MJO 291 when the leaks occurred) 14 cases on CFM56-5A (leaks occurred from 1400 H since using MJO 291) • Subsequent inspection revealed seals severely damaged with missing material • Affected seals are made of “fluorosilicone” material • Same design since day 1 on all CFM 56 models (170 million hours of experience) No leaks reported in CFM56-7B fleet SFH Gasket Seal - Oil leaks with MJO 291 High Temperature Oil Issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 7 Gasket between SFH and MHE SFH Gasket Seal - Oil leaks with MJO 291 High Temperature Oil Issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 8 Investigation Results • Gasket seal were returned to CFMI for extensive investigation to assess seal damage mechanism • Specific laboratory testing conducted to evaluate swelling and aging behavior of the fluorosilicone seal with MJO 291 versus other major oil brands (including other HTS oils) At different temperatures up to 160°C On oil types : MJO 291, MJO 291+MJO 254, MJO254, JT2, EXXON 2380 Results have shown that MJO 291 is more aggressive than other oil types SFH Gasket Seal - Oil leaks with MJO 291 Root Cause Identified to Be MJO 291 Associated With Temperature High Temperature Oil Issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 9 Investigation Results (cont’d) • Laboratory testing also conducted to evaluate swelling and aging behavior of the fluorocarbon seal with MJO 291 versus other major oil brands At different temperatures up to 160°C On oil types : MJO 291, MJO 291+MJO 254, MJO254, JT2, EXXON 2380 Thermal cycling, and endurance tests have demonstrated a very good behavior of this material versus MJO 291 characteristics and more generally versus oil types (including HTS oils) SFH Gasket Seal - Oil leaks with MJO 291 STATUS New problem only experienced on engines operating with MJO 291 oil CFMI & EXXON MOBIL are working the cause of the problem and define corrective actions High Temperature Oil Issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 10 Corrective Actions • Containment Plan CFMI recommends that CFM 56 operators (all CFM 56 engines models) using MJO 291 either consider a replacement of the gasket seal every 2,500 hours or discontinue the use of MJO 291 until the new gasket seal is available – FHL article issued in Aug 2001 – AOW issued 12 Dec 2001 • Final Fix Introduction of a new gasket seal design made of fluorocarbon material on CFM 56 models has been validated – In production, and field for CFM56-7B ===> Apr 2002 – New design fully interchangeable with current seal design SFH Gasket Seal - Oil leaks with MJO 291 High Temperature Oil Issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 11 Summary • HTS oils developed to reduce coking in the engine oil system MJO 291 validated on CFM 56 models in Oct 2000 after S.E completed • Since early 2001 cases of Oil leaks on CFM56-5A /-5B Engines operated with MJO 291 SFH/MHE gasket seal (fluorosilicon) found damaged with missing material Extensive lab analysis confirmed MJO 291 as the root cause of the problem • Containment plan and corrective actions defined FHL article (08/01) and AOW (Dec 12, 2001) issued recommending for operators using MJO 291 either to replace SFH/MHE gasket seal every 2500 H or discontinue use of MJO 291 pending new seal availability New gasket seal design (fluorocarbon material) in process to be introduced – In production and field on CFM56-7B by Apr 2002 SFH Gasket Seal - Oil leaks with MJO 291 High Temperature Oil Issues February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 12 Other areas with risks of leaks • CFMI has launched studies to list materials in contact with oil and assess sensitivity with new oils C&A list parts with fluorosilicon material (seals, sealants) ==> Completed Engine list parts with other non metallic materials in contact or susceptible to be spilled by the oil ===> Mar 2002 Action plan to be defined following studies – Technical risk of leak and subsequent corrective actions For fluorosilicon ===> Mid Feb 2002 Other non-metallic parts ===> Jun 2002 Oil leaks with MJO 291: Other Issues CFMI Still Working to Address the Problem and Define Corrective Actions Depending on Technical Risk Analysis High Temperature Oil Issues作者: 979199501 时间: 2011-4-15 23:55:02 标题: 回复 1# 航空 的帖子
Arm
Proposed Switch Configuration
Current Double Throw
Proposed Single Throw
Run contact eliminated
Introduction Logistics
• CFMI/Boeing/Honeywell laun作者: kinran 时间: 2011-6-4 23:19:56
