Document XRD9XqKzRw2a8JV9bJY6QMNqx

RED DENOTES HUBS THAT SPUN TK71 West M25 10.000 hp K71C Elliott 3BM K71B Elliott 60M K71A Elliott BGM GEARBOX GT71 W352 Gas turbine 50,000 hp AKERIFLEX #12-12 10000 hp 680,000 in lbs 4" bore K71C 4.5" bore TK71 o a-O2Th1 OD I> -2i WOO' 'IH* C^O ~o AK6HGEAR Marine type 5B18 hp 165, 409 in lbs 3.5" bore K71C 3.5" bore K71B APL 15 DBG COUPLING FAILURE ZURN MARINE TYPE CLASS I GEAR COUPLING SPACER DROPPED STRAIGHT DOWN ALL COUPLING BOLTS FAILED IN SHEAR (24 TOTAL, 3/8" DIAMETER, PLATED) BOLTS HAD IDENTICAL HARDNESS NUMBERS NO DAMAGE TO COUPLING COVER MINOR DAMAGE TO C CASE END OF GEARS ON SPACER ARL 14 DEC 89 DO A 0 3 6 1 3 1 C O N F ID E N T IA L KEY FAILURES KEY UNDER C CASE THRUST COLLAR SHEARED IN DIRECTION OF ROTATION SHAFT STOPPED. THRUST COLLAR CONTINUED TO ROTATE KEY IS MILD STEEL THRUST COLLAR FIT IS 0.001" LOOSE THRUST PADS ON C CASE IN GOOD SHAPE THEREFORE NO LOCKUP ACTIVE THRUST PADS ON B CASE VARNISHED AND CRACKED. NO BABBITT MOVEMENT BABBITT CAVED IN OVER THERMOCOUPLES IN INSTRUMENTED PADS ON B CASE ARL 14 DEC ae OONFTOFNTTAl ROTOR INFORMATION RESIDUE ON INTERSTAGE SUCTION (STAGE 4) OF THE 60M (B CASE) OTHER ROTORS APPEARED TO BE "CLEAN" ACTIVE THRUST BEARINGS ON B CASE WERE DAMAGED / ** KEY FAILURES C CASE WEST END ROTATING SEAL FACE KEY FAILED IN SHEAR AGAINST ROTATION SHAFT ACCELERATED AND SEAL FACE REMAINED STATIONARY KEY IS IN A Z SHAPE KEY FIT WAS LOOSE IN SEAL FACE CONFTDFNT o o o is. ARL 14 DEC S *T i^ S U ddO dHUdIHdHUci *iU t T<JS H380f 3fiU3lfl3HUS qu D -r- 2 n 1 ! GT120 SCENARIO FOR COMPRESSOR WRECK On 24 Deo there was a drop In performance of GT120 of approx 4* The Inlet temp was 5 degC. Sufficient to form loe on IGV's (consider pressure drop on IGV's) Ice broke free and damaged blade tips on row 1A Damage exolted natural frequencies of two row 1A blades OD 3 zT| o o~i > ti 3 HZ 3Cf\ orl 23 fab BO GT120 SCENARIO FOR COMPRESSOR WRECK At 2:30 am on 20 Dao on* of tha axoltad bladaa fallad Vibration dropped from 5.5 mils to 1.5 mile No drop In performanoe At 5:30 am on 29 Deo the aeoond exolted blade failed Maohlne tripped on low control oil pressure rt 23 fab BO DO A 0 3 6 1 4 0 OONFTDFNTTAl GT120 SCENARIO FOR COMPRESSOR WRECK The blades failed Independently Both blades failed from the leading edge to the trailing edge Leading edge mode of failure was fatigue Trailing edge mode of failure was duotlle (le. torn off) Will not be able to atlok Westlnghouse with the bill D0O)' art 23 fob M GT71 PT BLADE FAILURE JUNE 1990 NO WARNING PRIOR TO FAILURE PT BLADES HAD 29161 FIRED HOURS, 77 ATTEMPTED STARTS AND 24 SS NOT ENOUGH EVIDENCE TO DETERMINE INITIAL FAILED BLADE STRESS RUPTURE DATA ON WRECKED BLADES WAS WITHIN SPECIFICATION #3 BEARING WAS DESTROYED. POSSIBLY IT FAILED FIRST (NOT LIKELY). BLADE PARTS ARE AT WECAN. WAITING ON FEEDBACK FROM THEM. oo O Zo v- V* orl 2 Jan 9t O i. "''f)) n / im i /r CRACKED CT ROTOR HISTORY ORIGINALLY SHIPPED WITH THE SPARE ENGINE IN 1070 SPARE FOR 3 YEARS ON SITE. INSTALLED IN GT71 IN JULY 1002 REMOVED FROM SERVICE DURING LATE 1080 TURNAROUND RETURNED TO WECAN IN JANUARY 1067 FOR MODIFICATION ori a Jon tl DO A 0 3 6 1 4 4 OONFTDFNTTAl CRACKED CT ROTOR HISTORY page 2 ENCOUNTERED PROBLEMS REMOVING THE COMPRESSOR BLADES FROM THE SPINDLE. MACHINED THE BLADES OUT AND PURCHASED ROWS 4-13 NEW FOR INSTALLATION. IN TALLED THE ROTOR IN QT120 DURING THE MAY 1009 TURNAROUND. REMOVED THE ROTOR AFTER THE ROW 1A COMPRESSOR BLADE FAILURE DEC art S Jot 1 DO A 0 3 6 1 4 5 C O N F T O F N T IA l CRACKED CT ROTOR HISTORY page 3 HIPPED ROTOR TO WECAN FEBRUARY 1900 FOR REPAIR NOVEMBER 1990 WECAN INFORMED U8 OF THE CRACK8 IN THE BIRD BATH PORTION OF THE ROTOR AND RECOMMENDED THAT THE 8ECTION OF ROTOR BE DESTRUCTIVELY TESTED TO DETERMINE THE CRACK INITIATION. art a Jan 1 DO A 0 3 6 1 ,4 6 O O N F T O F N T IA l.