AN ENGINE REPAIR INSPECTOR REPORTS THAT DURING A ROUTINE BUILD-UP CYCLE OF A PW 2000 LPT; THE OUTSIDE VENDOR-OVERHAULED TURBINE REAR HUB WAS FOUND TO BE 0.010 OVERSIZE; EVEN THOUGH THE SERVICEABLE TAG SHOWS LESS.

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DURING NORMAL ROUTINE UP-CYCLE BUILD OF PW2000 LPT; THE OUTSIDE VENDOR-OVERHAULED TURBINE REAR HUB FAILED BUILD. THE REQUIRED FIT AND CLRNC BTWN THE 6TH STAGE TURBINE DISK/HUB AND THIS REAR HUB IS 0.000 TO 0.006T (TIGHT). THIS REAR HUB'S SNAP DIAMETER IS 0.010 OVERSIZE. THE ACR INSPECTION DOCUMENT MAX DIAMETER IS 9.600 -- THIS REAR HUB MEASURES 9.610. INSPECTION DOCUMENT SNAP SIZE OF 6TH STAGE DISK IS 9.600 TO 9.604. RECORD OF MEASUREMENT SUPPLIED WITH THE 8130-3 FOR THIS PART; RECORDS THIS SNAP DIAMETER AT 9.599. REF VENDOR COMPONENT SVCS 8130. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED THE ENTIRE LOW PRESSURE TURBINE (LPT) SECTION ATTACHES TO THE LOW PRESSURE TURBINE LONG SHAFT AT THE SPLINED REAR HUB; ALSO KNOWN AS THE 'COUPLING'; AT THE LPT SIXTH STAGE POSITION. THERE ARE FIVE STAGES OF LPT TURBINES; CALLED L-3; L-4; L-5; L-6; AND L-7 ON THE PW 2000 ENG. THERE ARE TWO HIGH PRESSURE TURBINES (HPT) KNOWN AS T-1 AND T-2. THE L-3; L-4; L-5 TURBINES ARE MOUNTED TO THE FORWARD SIDE OF THE L-6 COUPLING FLANGE AND L-7 ON THE AFT SIDE OF THIS HUB/COUPLING. REPORTER STATED HE IS AN ENGINE INSPECTOR AND THE 8130 SERVICEABLE TAG FROM THE OUTSIDE OVERHAUL VENDOR LISTED THE REAR HUB DIAMETER ON THE TAG AS LESS THAN THE ACTUAL DIAMETER HE MEASURED. THE ACTUAL REAR HUB DIAMETER WAS 0.010 OVERSIZE AND PREVENTED THE CONTINUED BUILD-UP OF THE LOW PRESSURE TURBINE SECTION.