标题: CFM 737 N1/N2 Vibration Team Report [打印本页] 作者: 航空 时间: 2011-4-15 08:59:01 标题: CFM 737 N1/N2 Vibration Team Report
作者: 航空 时间: 2011-4-15 08:59:13
1 Boeing and CFMI February 5, 2002 Proprietary Information 737 N1/N2 Vibration Team Report 2 Boeing and CFMI February 5, 2002 Proprietary Information 737 / CFM56-7B N1 Vibration / N2 Tone • The current aircraft / engine vibration related noise / vibration levels do not consistently meet customer expectations without significant flight line disruptions • Define / implement solutions with goal of B1/C1 • No quality impact Problem Statement Boeing / CFMI Team Charter N1/N2 – 3P Team Status 3 Boeing and CFMI February 5, 2002 Proprietary Information N2 Tone - 2001 • Ground Tone • Not a major flight line cause disruption • Can result in engine removals • In-Flight Tone • Not a problem since 10/99 S/W mod • Slight increase squawk activity in summer 2001 0 10 20 30 40 50 60 70 80 J a n M a r M a y J u l S e p N o v J a n M a r M a y J u l S e p N o v Month E n g in e S q u a w k R a t e - % RTV Buttons Squawk Rate Repeat Squawk Rate Flight Line N1 Vibe - 2001 Flight Line N1 Vibe Squawk Rates •Major flight line disruption cause • Low N1 vibe levels required to support delivery • Challenging VENOS (interior noise/vibe) delivery criteria • RTV/ Buttons have improved situation • Squawk / repeat squawk rates still unacceptable • AVM Solution / Fan Trim typically resolves squawks • Repeat squawks result in retrim, fan blade relube or engine removal Engine Vibe Related Squawk Distribution June to Sept 2001 7% 13% 77% 3% N1 AVM> 1.0 N1 AVM > 1.0 & A&T N1 A&T N2 N1 A&T Major Cause of Squawks 2000 2001 N1/N2 – 3P Team Status 4 Boeing and CFMI February 5, 2002 Proprietary Information Purpose: • -599 /Airplane Inst’l Effects • Optimized Balance Process • Determine Aircraft/Engine sensitivity to unbalance • Airplane Loading Impact / Flight maneuver effects Key Findings: • LPT unbalance verified / correct w/ 2-Plane trim • Quantified sensitivity to Fan/LPT unbalance • TRF sensor is better indicator of LPT unbalance than FFCC • Impact of fuel and airplane loading measured Production A/P Flt Test Eng -599 on YA106 Strut Shake Test YA106 ‘GVT’ Purpose: • Data to Develop Math Model for Airplane A&T prediction • Use to identify and evaluate fixes Key Findings: • Strut structure resonances found in N1and N2 ranges Eng -599 Investigation at CFMI Test Cell Purpose: • Compare Fan/LPT unbalance vs On-wing • Investigate LPT unbalance source • Quantify improvement to #5 ODB mod Key Findings: • Balance solution test cell vs. on-wing similar • High LPT unbalance confirmed • Not typical of current manufacturing process • Process change implemented to prevent reoccurrence • #5ODB testing scheduled Feb-Mar 20002 Solution Development Test YA106 (phase 2) Purpose: • FCSB / Fairing / Strut Transmissibility Test • Local N1 Treatment and Passenger Load Testing Key Findings: • Fuel loading has significant impact • N1 Tone reduction FCSB possible – testing TBD • Proposed N1 treatment not effective • Investigating new configuration N1/N2 – 3P Team Status 5 Boeing and CFMI February 5, 2002 Proprietary Information 3D MWFan Blades • Proceeding with immediate implementation of the following three solutions • 2 Plane Trim Balance (CFMI test cell) • 3D MW Fan Blades (CFMI new production) • Improved AVM Balance Algorithm (New A/Ps) • Assess flight line benefit for • N1 AVM, N1 Audible, N1 Tactile 2 Plane Trim Balance (LPT Balance) Improved AVM Balance Algorithm • Currently fan blades mapped for radial moment weight (MW) only • New procedure allows blades to be mapped for radial, tangential, and axial fan blade MW at new engine delivery • Results in fan blade sets with lower fan unbalance - Expect improvement in ability to trim balance engine to achieve lower vibe levels consistently - Minor improvements in N1 AVM and A&T • Intro at CFMI test cell Jan 2002 • No field impact regarding fan blades & procedures • Fan trim balance performed to reduce N1 engine vibe levels and N1 A&T • Currently assessing benefit of 2 plane trim balance for N1 A&T levels and flight line disruption rate • 2 plane trimmed (as req’d) at CFMI starting 888-769 • Flight line evaluation in progress • Go-Forward plans - April, 2002 • CFMI All OPS Wire issued Dec 2001 • S/B 72-0347R1 introduced LPT Stage 4 clips • Procedure not intended for in-service use • Improve quality of data collected for fan trim solutions • Speed ranges • Stability requirements • Coefficients • Reduce A/P noise and vibration and AVM levels •Improved ability to resolve squawks at >95% N1 • Available on production AVM units Q2 2002 • Retrofit not required, but available Category 1 Solutions N1/N2 – 3P Team Status 6 Boeing and CFMI February 5, 2002 Proprietary Information Other Solutions Being Considered • #5R Oil Damped Bearing Optimization • Local Airplane Treatment for N1 • Fan Blade Break-in • Optimized Fan Cowl Support Beam • #3R Bearing Clearance • Optimized Interior Modification for N2 tone • AVM and VENOS Measurement and Criteria • Active Vibration Control N1/N2 – 3P Team Status 7 Boeing and CFMI February 5, 2002 Proprietary Information Summary • Engine related N1 / N2 vibes are major flight line disruption cause • Boeing / CFMI team charted to implement solutions to achieve B1 / C1 goal • No quality impact • Category 1 solutions being implemented / evaluated - 1Q2002 • No in-service impact • Other potential solutions being considered - 4Q2002 N1/N2 – 3P Team Status作者: kinran 时间: 2011-6-4 23:24:38
作者: bocome 时间: 2011-7-31 04:45:43
CFM 737 N1/N2 Vibration Team Report作者: bei1999 时间: 2016-5-3 06:09:48
