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This technical data is considered EAR controlled pursuant to 15 CFR Parts 730-774 respectively. Transfer of this data by any means to a Non-US Person, whether in the United States or abroad, without the proper U.S. Government authorization (e.g., License, exemption, NLR, etc.), is strictly prohibited.
Copyright (2014) General Electric Company, U.S.A.
TRANSMITTAL INFORMATION
REVISION 1 TO SERVICE BULLETIN 72-0136
Revision 1 is issued to update paragraphs 1., PLANNING INFORMATION
, 2., MATERIAL INFORMATION
, and 3., ACCOMPLISHMENT INSTRUCTIONS
.
The original was issued June 05, 2013. Revision bars in the left margin identify changes.
1.PLANNING INFORMATION
A.Effectivity
* * * FOR GEnx-1B54, -1B58, -1B64, -1B67, -1B70, 1B54/P1, -1B58/P1, -1B64/P1, -1B67/P1, -1B70/P1, -1B70/72/P1, -1B70/75/P1, -1B74/75/P1, 1B75/P1
This Service Bulletin has been introduced in production to these GEnx-1B engines:
•
GEnx-1B engines, serial numbers 956-291 and up.
These serial numbers are the best available data.
B.Description
 This Service Bulletin releases a new dome assembly (dome), P/N 2258M79G02 for production use. This part contains a new manufacturing procedure to attach the deflector to the dome plate, improving the resultant braze quality. The gap between the deflector and dome plate has been increased and braze alloy processing has been changed to improve braze bonding.
 This Service Bulletin directs a one time inspection of existing domes P/N 2258M79G01 when exposed per a modification procedure defined in the Repair Document (RD) 124-1247. The RD 124-1247 defines the inspection and modification of the dome P/N 2258M79G01 involving the replacement of 22 deflectors and remarking the part to P/N 2258M79G02.
C.Compliance
Category 6
 GE recommends that you do this Service Bulletin when the combustor is routed for repair.
NOTE:
This Service Bulletin can be accomplished in shop.
This Service Bulletin is offered to improve the reliability or performance of your GE product, or to help prevent the occurrence of the event or condition described in this Service Bulletin. If the operator elects not to participate in the bulletin, that decision will be taken into consideration by GE in evaluating future product performance issues that may arise in the operators fleet.
D.Concurrent Requirements
None.
E.Reason
(1)Objective:
 To introduce a new part, improve reliability, document inspection of existing domes P/N 2258M79G01, and upgrade, if necessary, using the RD 124-1247 to replace all 22 defective deflectors.
(2)Condition:
 Current domes P/N 2258M79G01 have been found to have cracks in the braze joint that attach the deflectors to the dome plate when inspected after operation. Metallurgical analysis of the domes found internal voiding and cracking in the joint.
(3)Cause:
Braze cracking with the current application method is due to insufficient braze alloy coverage and limited effectiveness of the nickel plating applied to current deflectors.
(4)Improvement:
 A new dome is herein released with an improved braze joint. The process change was found to result in a more reliable braze joint and reduced internal and external braze defects. The improvement involves optimization of the braze gap between the deflector and dome plate and the addition of sintered braze tape in place of nickel plating. Comparable changes have been incorporated into the GEnx-1B CIR for the replacement of deflectors. The replacement modification procedure converts the domes P/N 2258M79G01 to the P/N 2258M79G02 configuration.
(5)Substantiation:
Substantiation is by analysis and comparative analysis.
F.Approval
This Service Bulletin has been reviewed by the appropriate governmental authority and the repair(s) and modification(s) herein comply with the applicable Federal Aviation Regulations and are FAA APPROVED for installation in the model(s) listed in this Service Bulletin.
G.Manpower
No additional man-hours are required to comply with this Service Bulletin.
H.Weight and Balance
Weight and balance are not changed.
I.References
 GEK 9250, Commercial Engine Standard Practices Manual (SPM)
GEK 112862, GEnx-1B Cleaning, Inspection and Repair Manual (CIR)
GEK 112864, GEnx-1B Engine Illustrated Parts Catalog (EIPC)
 Repair Document (RD) 124-1247 (P1 or Higher) Combustion Chamber Dome - Alteration - Replacement of the Deflectors
NOTE:
The reference documents listed below are for the engine manufacturer's internal use only:
 
CID: 573832
 
BPP: 12-72-41-04
J.Publications Affected
GEK 112862, GEnx-1B Cleaning, Inspection and Repair Manual (CIR)
GEK 112864, GEnx-1B Engine Illustrated Parts Catalog (EIPC)
K.Interchangeability
Two-way interchangeable.
L.Software Accomplishment Summary
Not applicable.
2.MATERIAL INFORMATION
A.Material - Price and Availability
(1)Parts necessary to do this Service Bulletin:
None.
(2)Other Spare Parts:
 
Part Number
Qty/Eng
Part Name
Unit ($) Price
Pkg Qty
Lead Time Days
 
2258M79G02
(1)
Dome Assembly
282,800.00
(1)
30
NOTE:
Prices are provided for planing purposes and are subject to change.
(3)Consumables:
None.
B.Industry Support Information
None.
C.Configuration Chart
 
New Part Number
Qty/ Eng
Part Name
Old Part Number/ IPC Location
Qty/ Eng
Op Code
Chg/ Sprt Code
 
2258M80G01/G06
(X)
Combustion Chamber Assembly
2258M80G01/G06
(X)
RM
-/-
 
.2258M79G02
01-090A, 72-42-00
(1)
Dome Assembly
(SIN 12400 8)
.2258M79G01
01-090, 72-42-00
(1)
RW/RE
2/B
Operation Codes
RE=Replace
RM=Remains
RW=Rework
Change Code
2=Two-way interchangeable.
Support Code
B=Old parts will be supplied until all old parts are sold.
D.Parts Disposition
 At the combustor assembly, there is no action required. Do an inspection of the dome P/N 2258M79G01 when it is exposed (combustor at piece part level). Refer to the GEnx-1B CIR, 72-42-03, INSPECTION 001 and ultrasonic inspection defined in paragraph 3., ACCOMPLISHMENT INSTRUCTIONS. Repair or replace deflectors as necessary. If less than 22 deflectors require replacement, refer to the GEnx-1B CIR, 72-42-03, REPAIR 005. If replacement of 22 deflectors is required, refer to RD 124-1247.
E.Tooling - Price and Availability
None.
3.ACCOMPLISHMENT INSTRUCTIONS
A.Inspection
 (1)The disassembly instructions for the combustor assembly have not changed. Refer to GEnx-1B CIR, 72-00-42, REPAIR 001.
 (2)Do a visual inspection of the dome, at piece part level, for deflector braze cracks at 22 places. Refer to the GEnx-1B CIR, 72-42-03, INSPECTION 001, Subtask 72-42-03-220-050.
 (a)If cracks are identified, the part is not serviceable.
 (3)If necessary, do an ultrasonic inspection of the dome P/N 2258M79G01 deflector braze coverage at the 22 places using an approved GE procedure. Refer to the SPM, 70-32-00, INDIRECT INSPECTION METHODS and 70-32-06, ULTRASONIC INSPECTION. If defects are identified, the part is not serviceable. The limits for ultrasonic inspection defects are as follows:
 (a)Through voids are not permitted.
 (b)Single imperfections 0.040 sq in. (0.26 sq cm) or less are permitted.
 (c)A total area of void, porosity, unbonded areas, and inclusions of 20 percent or less compared to the total joint area is permitted.
 (4)Repair the dome by replacing unserviceable deflectors. Refer to RD 124-1247 and do as follows:
 (a)If less than 22 dome deflectors are replaced, the dome part number remains P/N 2258M79G01. If the 22 dome deflectors are replaced, the dome can be remarked to P/N 2258M79G02.