TASK 72-50-21-300-031 LPT Case - Weld Repair Cracks At The Outer Duct Support Hook By Stop Drill And Plug, Repair-031 (VRS4343)

DMC:V2500-A0-72-50-2101-02A-627A-C|Issue No:002.00|Issue Date:2013-11-01

Export Control

EAR Export Classification: Not subject to the EAR per 15 C.F.R. Chapter 1, Part 734.3(b)(3), except for the following Service Bulletins which are currently published as EAR Export Classification 9E991: SBE70-0992, SBE72-0483, SBE72-0580, SBE72-0588, SBE72-0640, SBE73-0209, SBE80-0024 and SBE80-0025.

Copyright

© IAE International Aero Engines AG (2001, 2014 - 2021) The information contained in this document is the property of © IAE International Aero Engines AG and may not be copied or used for any purpose other than that for which it is supplied without the express written authority of © IAE International Aero Engines AG. (This does not preclude use by engine and aircraft operators for normal instructional, maintenance or overhaul purposes.).

Applicability

All

Common Information

TASK 72-50-21-300-031 LPT Case - Weld Repair Cracks At The Outer Duct Support Hook By Stop Drill And Plug, Repair-031 (VRS4343)

Effectivity

FIG/ITEM

PART NO.

01-010

3A0807

01-010

3A0990

01-010

3A0991

01-010

3A1908

01-010

3A2183

01-010

3A2265

01-010

3A2447

01-010

3A2533

Material of component

DESCRIPTION

SYMBOL

MATERIAL

LP turbine case

MTS1101D/Inconel 718

General

Price and availability - none

The practices and processes referred to in the procedure by the TASK numbers are in the SPM.

This repair can be done at module level and at piece part level.

NOTE

For equipment and materials necessary to do this repair, refer to the SPM TASK 70-23-05-230-501 and SPM TASK 70-31-13-310-501.

NOTE

To identify the consumable materials, refer to the PCI.

Preliminary Requirements

Pre-Conditions

NONE

Support Equipment

NameManufacturerPart Number / IdentificationQuantityRemark
Electric hand drillLOCALElectric hand drill
Hand held grinderLOCALHand held grinder

Consumables, Materials and Expendables

NameManufacturerPart Number / IdentificationQuantityRemark
CoMat 03-284 WELDING FILLER WIRE, NiBASELOCALCoMat 03-284

Spares

NONE

Safety Requirements

NONE

Procedure

    1. SUBTASK 72-50-21-230-054 Examine the Area A1, A2 and A3 of the LP Turbine Case for Cracks

    1. Refer to: Figure

      2. Do the test for cracks.

      1. Refer to the SPM TASK 70-23-05-230-501.

        Use Medium sensitivity level.

        Repair the cracks if they go across in area A1.

        Cracks in area A2 must not be repaired.

        Cracks in area A3 cannot be repaired by this procedure.

    2. SUBTASK 72-50-21-350-067 Machine the Cracks at the LP Turbine Case

      CAUTION

      IF THE MODULE IS NOT DISASSEMBLED, DRILL THE HOLE IN SOME STEPS. BEFORE THE DRILL FINALLY BREAKS THROUGH, CLEAN OUT THE HOLE REGULARLY WITH A COMPRESSED AIR GUN. THIS WILL KEEP SWARF PRODUCTION IN THE BACK END OF THE HOLE TO A MINIMUM.

      NOTE

      All stop holes are to be at the same radial location as the cooling air holes.

      NOTE

      If the module is not disassembled, you must not deburr the stop holes on the rear side.

      1. Drill stop holes.

      1. For dimensions refer to Figure.

        Every stop hole have to be radially in line with the crack.

        Maintain minimum distance between the holes.

        If projected radial growth of a crack does not align to an existing air hole but is within permitted minimum distance of two holes, the stop hole must be as near as possible to existing cooling air hole.

        Use electric hand drill with a drill.

        For drill diameter refer to stop bore diameter tolerance in Figure.

    3. SUBTASK 72-50-21-220-067 Examine the Repaired Areas for Cracks

      1. Do the test for cracks at the stop holes.

      1. Refer to the SPM TASK 70-23-05-230-501.

        Use medium sensitivity level.

        Cracks ending in a stop hole are permitted.

        Cracks starting in a stop hole radially outside of the stop hole centerline are not permitted.

    4. SUBTASK 72-50-21-310-059 Prepare the Plug-Pin

      1. Prepare the plug-pin.

      1. Cut a pin with applicable diameter 0.062 to 0.094 in. (1.60 to 2.40 mm) to a length of 0.220 to 0.230 in. (5.60 to 6.80 mm).

        Make sure that the pin diameter is smaller than the stop hole diameter.

        Refer to Figure.

        Lightly peen or melt one end of the pin to make it oval shaped.

      2. CAUTION

        PLUG ALL STOP HOLES. DO NOT PLUG THE AIR COOLING HOLES.

        NOTE

        This gives an interference fit between the plug and the stop hole to be plugged.

        NOTE

        After plugging, a total of 10 air cooling holes that are 0.114 - 0.125 in. (2.90 - 3.20 mm) diameter must be open.

        Install the plug in the stop hole.

      1. Install the end of the plug that is not deformed into the stop hole from the side of the outer duct support hook to be welded.

        Use a drift or punch to make the plug flush with the weld surface.

        Refer to Figure.

    5. SUBTASK 72-50-21-310-060 Tack Weld the Plug

      1. Tack weld the plug.

      1. Refer to the SPM TASK 70-31-13-310-501.

        Use gas tungsten arc weld technique and CoMat 03-284 WELDING FILLER WIRE, NiBASE.

        Keep heat input to a minimum.

        Refer to Figure.

        Stress relief after welding is not necessary.

    6. SUBTASK 72-50-21-320-069 Machine the Welded Areas

      1. If necessary, grind the welds.

      1. Grind the head of the plug or the tack weld until it is flush with the adjacent surface.

        Use hand held grinder.

    7. SUBTASK 72-50-21-220-175 Examine the Welded Areas

      1. Examine the plug or the tack weld.

      1. Make sure that the plug is correctly installed.

        Welded areas must be equal to the original contours and must be flush with the adjacent surfaces.

    8. Figure: Stop drilling of cracks at the outer duct support of the LP turbine case

    Sheet 1

    Legend
    Stop drilling of cracks at the outer duct support of the LP turbine case

    Sheet 1

    Close

    Figure: Stop drilling of cracks at the outer duct support of the LP turbine case

    Sheet 2

    Legend
    Stop drilling of cracks at the outer duct support of the LP turbine case

    Sheet 2

    Close

    Figure: Tack weld the plug at the outer duct support of the LP turbine case

    Tack weld the plug at the outer duct support of the LP turbine case

Requirements After Job Completion

Follow-On Conditions

NONE
Change Type:

Editorial correction due to conversion

Manufacturer Code:LOCAL
Enterprise Name:LOCALLY SUPPLIED
Manufacturer Code:LOCAL
Supply Number:CoMat 03-284
Type:sp01
Supply Short Name:CoMat 03-284 WELDING FILLER WIRE, Ni BASE
Supply Name:CoMat 03-284 WELDING FILLER WIRE, NiBASE
Specification Groups:
Doc NumberType
INCONEL 718 AMS 5832 AWS 5.14 MSRR9500/220
INCONEL 718 AMS 5832 AWS 5.14CLASS ER NI FE Cr-2 OMAT:3/206
INCONEL 718 AMS 5832 AWS 5.14CLASS ER NI FE Cr-2
Suppliers:
ManufacturerRemarks
LOCAL
28553
IE137
08489
IE508
0ZDB5
2R602
55596
58401
80357
K6835
Manufacturer Code:LOCAL
Tool Number:Electric hand drill
Tool Name:Electric hand drill
Manufacturer Code:LOCAL
Tool Number:Hand held grinder
Tool Name:Hand held grinder