TASK 72-41-34-200-007-C00 HPC Stage 4 Unison Rings - Examine, Inspection-007

DMC:V2500-A0-72-41-3424-00C-300A-C|Issue No:004.00|Issue Date:2019-08-01

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 72-41-34-200-007-C00 HPC Stage 4 Unison Rings - Examine, Inspection-007

Effectivity

FIG/ITEM

PART NO.

04-440

6A7888

04-440

6A8121

04-540

6A7890

General

This TASK gives the procedure for the inspection of the stage 4 upper and lower unison rings.

Fig/item numbers in parentheses in the procedure agree with those used in the EIPC. Only the primary Fig/item numbers are used. For the service bulletin alpha variants refer to the EIPC.

The policy that is necessary for inspection is given in SPM TASK 70-20-01-200-501.

All the parts must be cleaned before any part is examined.

All the parts must be visually examined for damage, corrosion and wear. Any defects that are not identified in the procedure must be referred to IAE.

The procedure for those parts which must have a crack test is given in Step. Do the crack test before the part is visually examined.

Do not discard any part until you are sure there are no repairs available. Refer to the instructions in Repair before a discarded part is used again or oversize parts are installed.

Parts which should be discarded can be held although no repair is available. The repair of a discarded part could be shown to be necessary at a subsequent date.

All the parts must be examined to make sure that all the repairs have been completed satisfactorily.

The practices and processes referred to in the procedure by the TASK/SUBTASK number are in SPM.

References

Refer to SPM for data on these items:

Definition of Damages, SPM TASK 70-02-02-350-501,

Record and Control of the Lives of Parts, SPM TASK 70-05-00-220-501,

Inspection of Parts, SPM TASK 70-20-01-200-501.

Some data on these items is contained in this TASK. For more data on these item refer to SPM:

Method of Testing for Crack Indications,

Chemical Processes,

Surface Protection.

Preliminary Requirements

Pre-Conditions

NONE

Support Equipment

NONE

Consumables, Materials and Expendables

NONE

Spares

NONE

Safety Requirements

NONE

Procedure

    1. SUBTASK 72-41-34-230-128 Examine the Stage 4 Upper and Lower Unison Rings for Cracks

    1. Clean the parts. Refer to TASK 72-41-34-100-000 (CLEANING-000).

    2. Do the test for cracks on the parts that is given below.

      PART IDENT

      TASK/SUBTASK

      Stage 4 upper and lower unison rings for cracks

      3. Cracked.

      1. Reject.

    2. SUBTASK 72-41-34-220-390 Examine the Stage 4 Upper and Lower Unison Rings Bodies at Locations 1 and 2

    1. Refer to Figure.

      2. Nicked.

        1. Up to 0.005 in. (0.13 mm) in depth.

        1. Accept.

        2. More than in Step.

        1. Repair, VRS6186 TASK 72-41-34-300-048 (REPAIR-048).

      3. Scored.

        1. Up to 0.005 in. (0.13 mm) in depth.

        1. Accept.

        2. More than in Step.

        1. Repair, VRS6186 TASK 72-41-34-300-048 (REPAIR-048).

      4. Scratched.

        1. Up to 0.005 in. (0.13 mm) in depth.

        1. Accept.

        2. More than in Step.

        1. Repair, VRS6186 TASK 72-41-34-300-048 (REPAIR-048).

    3. SUBTASK 72-41-34-220-427 Examine the Stage 4 Upper and Lower Unison Stop Rivets at Locations 3

    1. Refer to Figure.

      2. Stop Rivets.

        1. Loose.

        1. Reject.

        2. Missing.

        1. Reject.

        3. Weld cracked.

        1. Repair, VRS6544 TASK 72-41-34-300-064 (REPAIR-064).

    4. SUBTASK 72-41-34-220-391 Examine the Stage 4 Upper and Lower Unison Rings Brackets at Locations 4 and 5

    1. Refer to Figure.

      2. Screw thread nuts at locations 4 and 5.

        1. Broken.

        1. Repair, VRS6155 TASK 72-41-34-300-013 (REPAIR-013).

        2. Crossed threads.

        1. Repair, VRS6155 TASK 72-41-34-300-013 (REPAIR-013).

        3. Threads that are not there.

        1. Repair, VRS6155 TASK 72-41-34-300-013 (REPAIR-013).

    5. SUBTASK 72-41-34-220-392 Examine the Stage 4 Upper and Lower Unison Rings Dowels at Locations 6

    1. Refer to Figure.

      2. Missing.

      1. Reject.

      3. Worn diameter.

        1. More than 0.4340 in. (11.016 mm).

        1. Accept.

        2. Less than Step.

        1. Reject.

      4. Screw thread inserts.

        1. Broken.

        1. Repair, VRS6156 TASK 72-41-34-300-014 (REPAIR-014).

        2. Crossed Threads.

        1. Repair, VRS6156 TASK 72-41-34-300-014 (REPAIR-014).

        3. Threads that are not there.

        1. Repair, VRS6156 TASK 72-41-34-300-014 (REPAIR-014).

    6. SUBTASK 72-41-34-220-393 Examine the Stage 4 Upper and Lower Unison Rings Bushes at Locations 7

    1. Refer to Figure.

      2. Inner bore.

        1. Scored.

        1. Repair, VRS6247 TASK 72-41-34-300-049 (REPAIR-049).

        2. Scratched.

        1. Repair, VRS6247 TASK 72-41-34-300-049 (REPAIR-049).

        3. Worn.

          1. Less than 0.201 in. (5.112 mm) in diameter.

          1. Accept.

          2. More than in Step.

          1. Repair, VRS6247 TASK 72-41-34-300-049 (REPAIR-049).

      3. Bushes that are not there.

      1. Repair, VRS6247 TASK 72-41-34-300-049 (REPAIR-049).

      4. Excessive bush movement (side to side).

      1. Repair, VRS6247 TASK 72-41-34-300-049 (REPAIR-049).

    7. Figure: Stage 4 Upper And Lower Unison Rings - Inspection Locations

    Stage 4 Upper And Lower Unison Rings - Inspection Locations

Requirements After Job Completion

Follow-On Conditions

NONE
Change Type:

Revised the procedure to add repair reference. (19VG015)