ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

CFM PROPRIETARY INFORMATION

The information contained in this document is CFM proprietary information and is disclosed in

confidence. It is the property of CFM and shall not be used, disclosed to others or reproduced

without the express written consent of CFM, including, but without limitation, it is not to be used in

the creation, manufacture, development, or derivation of any repairs, modifications, spare parts,

design, or configuration changes or to obtain FAA or any other government or regulatory approval

to do so. If consent is given for reproduction in whole or in part, this notice and the notice set

forth on each page of this document shall appear in any such reproduction in whole or in part.

The information contained in this document may also be controlled by U.S. export control laws.

Unauthorized export or re-export is prohibited.

All technical documentation and information contained herein, with respect to assembly and

disassembly, cleaning, inspection methods and limits, repair methods and limits, operational

limits, life limits and the like, have been developed and approved for use with engines and parts

that have been manufactured and/or approved by CFM and that have been maintained in

accordance with CFM technical documentation and recommendations. CFM has no contractual

or legal obligation for, nor knowledge of, non-CFM-approved parts and repairs. Accordingly, this

document is not intended to apply to non-CFM-approved parts and repairs.

CFM56-5B S/B 72-0850

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

1. PLANNING INFORMATION

A. Effectivity

CFM56-5B1, -5B2, -5B4, -5B5, -5B6, -5B7

CFM56-5B1/P, -5B2/P, -5B3/P, -5B4/P, -5B5/P, -5B6/P, -5B7/P, -5B8/P, -5B9/P

CFM56-5B3/P1, -5B4/P1

(1) This Service Bulletin affects all Turbine Rear Frames (TRF) P/N 338-102-907-0 and

338-102-908-0 installed on CFM56-5B engine model.

B. Description

This Service Bulletin gives instructions for on wing or in shop inspection of the TRF struts

in order to increase the life of the TRF. The three mount struts of the TRF have to be

inspected. Refer to Figure 1.

C. Compliance

Category 7

Do at customer convenience but before the TRF reaches 32,000 cycles since new for

commercial engine models and 25,000 cycles for corporate jet engine models (CFM56-5B6,

-5B7, -5B6/P, -5B7/P).

For TRF disposition/re-inspection intervals, refer to paragraphs 3.D.(2) and 3.E.(2).

NOTE: The Service Bulletin can be accomplished in shop or on wing.

D. Concurrent Requirements

None.

E. Reason

(1) Objective:

To do an inspection.

To increase the life of the TRF. Refer to Engine Shop Manual ATA 05-12-04 for life

limits and to Engine Shop Manual ATA 05-21-03 for inspections.

(2) Condition:

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

TRF may exhibit cracks, initiating at leading and trailing edge of the mount struts, in

the transition radius between the struts and in the outer ring fillet radius.

(3) Cause:

High thermal gradient between the struts and the outer ring.

(4) Improvement:

This Service Bulletin provides the procedure and equipment to inspect the TRF

mount struts.

(5) Substantiation:

Substantiation is by analysis.

F. Approval

The technical content of this document is approved by the FAA and under the authority of

DOA n°EASA.21J.086.

G. Manpower

You will need approximately 3 man-hours for each engine to do this Service Bulletin. This

estimation does not include the time needed to get access to the inspection areas.

H. Weight and Balance

Weight and Balance are not changed.

I. References

CFM56-5B Engine Shop Manual , CFMI-TP.SM.9

A318/A319/A320/A321 Aircraft Maintenance Manual

CFM56 Consumable Products Manual , CFMI-TP.CP.3

CFM56 Standard Practice Manual , CFMI-TP.SP.2

J. Publications Affected

CFM56-5B Engine Shop Manual , CFMI-TP.SM.9 ATA 05-12-04, 05-21-03 and 72-56-01.

CFM56-5B S/B 72-0850

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

K. Interchangeability

The physical and the functional interchangeabilities are not affected.

L. Software Accomplishment Summary

None.

2. MATERIAL INFORMATION

A. Material - Price and Availability

(1) Parts necessary to do this Service Bulletin:

None.

(2) Other Spare Parts:

None.

(3) Consumables:

Code Number Description

CP1040 Methyl Ethyl Ketone

CP2189 Durite G422

CP2191 Durite G421

B. Industry Support Information

None.

C. Configuration Chart

None.

D. Disposition of Parts

None

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

E. Tooling - Price and Availability

Description Supplier

Nortec Model NDT 19, 19e, 19e2, 24,

1000, 1200 or -3000.

OLYMPUS NDT

421 North Quay Street

WA 99336

KENEWICK

USA

or

ANAFAB

3 avenue Marcel Dassault

78310 Coigneres

FRANCE

Rohman Elotest family Rohmann GmbH

Rudolf-Diesel-Str.13

D-67227 Frankenthal

DEUTCHLAND

or

Intercontrole IC ESCOFFIER

Parc d'activités de la route des lacs

BP 612

27106 VAL DE REUIL

FRANCE

NOTE 1: Any equivalent equipment approved by Snecma/CFM can be used instead of

listed above.

Tool No. Description

856A2692G01 Eddy current inspection kit of rear frame

NOTE 2: The inspection kit containing all required tooling can be obtained from CFM

by contacting the following address:

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

North and South America and Asia Customers

CFM Inc. Customers

Europe, Middle East and Africa Customers

CFM SA Customers

CFM international

Quality Technology Center

One Neumann Way, MD:

QB Cincinnati, OH 45215 USA

Attention: Brenda Tenley

Phone: (513)552 4701

Fax: (513)552 4892

e-mail: brenda.tenley@ge.com

CFM international

Snecma

Manager CFM56 Tooling Programms

Site de Melun-Montereau

BP 1936

77019 Melun Cedex

FRANCE

Phone: 33 1 64 14 80 89

Fax: 33 1 64 14 87 65

e-mail: snecma.tooling@snecma.fr

3. ACCOMPLISHMENT INSTRUCTIONS

A. General

WARNING: METHYL ETHYL KETONE IS TOXIC. USE PERSONAL PROTECTION

EQUIPMENT. USE IN A WELL-VENTILATED AREA.

(1) Get access to the TRF for on wing inspection.

(a) Remove the primary nozzle assy. Refer to Aircraft Maintenance Manual

(AMM), ATA 78-11-01, TASK 78-11-01-000-801.

(b) Remove the primary plug assy. Refer to AMM, ATA 78-11-02, TASK

78-11-02-000-801.

(2) Get access to the TRF for on wing or in shop inspection.

(a) Remove the flame arrestor and the rear cover. Refer to AMM, TASK

72-56-00-000-802 or Engine Shop Manual (ESM) ATA 72-00-03 REMOVAL

001

(3) Do a visual inspection of the areas to be inspected. Mark on the part at the location

of all blends, nicks, or other anomalies which may cause an indication during the

inspection. If needed use Methyl Ethyl Ketone (CP1040) , Durite G422 (CP2189) or

Durite G421 (CP2191) to clean the part.

B. Eddy current calibration and inspection:

The four specific areas to be inspected on the three mounts struts position 1, 3 and 14 are

detailed on Figure 1. The calibration block is described on Figure 2.

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

(1) Calibrate the eddy current instrument to the initial settings as follows:

(a) Permit the eddy current instrument to warm up. Refer to the instructions

of the manufacturer.

(b) Set the eddy current instrument to the initial settings as below with the example

of Rohmann Elotest B300 instrument.

Instrument type Frequency Range Gain Filters

Elotest B300 1 to 2 MHz Preamplifier: auto LP: 100

HP: STATIC

(c) Eddy Current probe(s) from the kit, : 9970-958-574, 9970-958-575,

9970-958-576.

(d) Calibration block from the kit, : 9970-958-579. Refer to Figure 2.

(e) Apply teflon from the kit, to the probe.

(f) Put the probe of the inspection kit on the calibration standard away from the

EDM notches and null the probe.

(2) Scan across the EDM notch at a speed equal to the one that will be used during

the inspection and adjust the instrument gain, phase and dot position so that the

peak response from the EDM notch dimension 0.020 inch (0,5 mm) x 0.004 inch

(0,1 mm) has an amplitude equal to 1.5 or 2 Volts depending on the probe. Refer

to Figure 3 to Figure 5.

NOTE 1: Repeat the steps 3.B.(1)(e), 3.B.(1)(f) and 3.B.(2) for each probe

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

NOTE 2: Personnel performing these inspections must be certified to one of

the following: NAS 410 / EN4179 level 2 minimum or any equivalent

standard as recognized by the airworthiness authority of the personnel.

Personnel performing this inspections should receive practical training

in the use of this procedure and must demonstrate proficiency in the

calibration, inspection and evaluation routines before accept/reject

authority is delegated.

Training, which can be provided regarding the performance of this

inspection, does not imply that personnel who receive that training have

met the requirements of inspector certification in accordance with note 2

above.

Contact your customer team if you think you need such a training.

(3) Inspection.

(a) See locations and dimensions of the areas to be inspected:

– Location A, refer to Figure 6,

– Location B1, refer to Figure 7,

– Location B2, refer to Figure 8.

(b) Inspect 3 areas as follows:

1 Using the appropriate probe, scan in two directions of all the areas as it is

shown on each figure. Pay special attention near the variation of shapes.

– Probe 9970-958-576, Figure 6 location A.

– Probe 9970-958-574, Figure 7 location B1.

– Probe 9970-958-575, Figure 8 location B2.

(c) In case of indication over the limits of the screen (for example due to cracks

which pass through the thickness of the flange) reduce the amplitude by steps

of 6 db as much time as it is necessary to reach an interpretable signal.

NOTE: As we perform a manual inspection, the way to inspect has to be the

closest to the theoretic scanning shown on the figures (not strictly).

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

1 Evaluate the horizontal and vertical indications that are equal to or more

than half of calibration level for each probe.

9970-958-574 and 9970-958-576 : 750 millivolts or 1.5 divisions.

9970-958-575: 1,000 millivolts or 2 divisions,

2 Clean and re-inspect the area in different scanning directions to check

the indication.

3 After completion of the indication evaluation procedure, if the indication is

still equal to or more than 1,000 millivolts or 750 millivolts (depending on

the probe used), note the place of the indication on the part.

4 Scan perpendicularly to the defect to determine its length. Refer to Figure

9.

(4) Calibration check.

Do a calibration/check after each area inspection (and or each probe) as follows:

NOTE: The calibration check must be done with initial calibration settings.

(a) Do a calibration check after each inspection, when a system component or

inspector is changed, or when the inspector suspects a change may have

occurred in the inspection.

(b) If the peak notch response is within 10% more or less, the calibration is

acceptable.

(c) If the amplitude of the response from the EDM notch has decreased by more

than 10%, re-calibrate and re-inspect all areas inspected since the previous

calibration.

(d) If the amplitude of the response from the EDM notch has increased by more

than 10%, re-calibrate and re-inspect any areas which were previously found

to be rejected since the previous calibration.

C. Alternative Procedure. Fluorescent Penetrant Inspection (FPI) at piece part level.

CAUTION: PARTS MUST BE THOROUGHLY CLEANED BEFORE BEING SUBJECTED

TO THE FLUORESCENT PENETRANT INSPECTION TO ACCOMPLISH

A PROPER INSPECTION AND TO PREVENT CONTAMINATION OF THE

INSPECTION MATERIALS.

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

CAUTION: PAY PARTICULAR ATTENTION TO THE AREAS TO BE INSPECTED. IF

THERE IS ANY DOUBT, PERFORM THE EDDY CURRENT INSPECTION.

(1) Perform a FPI according to Standard Practice Manual (SPM) 70-32-14 on the

areas to be inspected:

– Location A, refer to Figure 6

– Location B1, refer to Figure 7

– Location B2, refer to Figure 8.

D. Inspection intervals for CFM56-5B commercial engine applications:

Mandatory inspection interval for TRF P/N 338-102-907/-908-0

(1) If no crack is found on any of the three mount struts, the TRF is serviceable and

must be re-inspected at 2,500 cycles repetitive intervals.

(2) If cracks are found on the mount struts, the TRF must be re-inspected according to

the following repetitive intervals:

Total cumulated crack length at each location Re-inspection interval within

L < 0.20 (5)

0.20 (5) ≤ L < 0.25 (6,5)

L ≥ 0.25 (6,5)

2,500 cycles

370 cycles

Immediately remove the turbine frame

Repetitive inspection interval of every location is driven by the minimum reduced

interval.

NOTE 1: Dimensions are in inches with millimeters in parentheses.

NOTE 2: For each mount strut:

– If one single crack, measure crack length.

– If multiple cracks, cumulate crack length.

NOTE 3: After TRF removal, cracks may be repairable using the limits provided

in Engine Shop Manual ATA 72-56-01 Inspection 001. Even after

the cracks are repaired, the TRF must still be re-inspected using the

intervals above.

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

NOTE 4: Three inspection locations on mounts struts (1, 3 and 14):

– Location A: leading edge top end strut, pressure side and suction

side.

– Location B1: the outer casing fillet radius close to rear flange at

mount area (flow path side).

– Location B2: the outer casing fillet radius close to rear flange at

mount area (opposite to the flow path).

E. Inspection intervals for CFM56-5B Corporate Jet applications:

Mandatory inspection interval for TRF P/N 338-102-907/908-0

(1) If no crack is found on any of the three mount struts, the TRF is serviceable and

must be re-inspected at next 1,670 cycles repetitive intervals.

(2) If cracks are found on the mount struts, the TRF must be re-inspected according to

the following repetitive intervals:

Total cumulated crack length at each location Re-inspection interval within

L < 0.20 (5)

0.20 (5) ≤ L < 0.25 (6,5)

L ≥ 0.25 (6,5)

1,670 cycles

280 cycles

Immediately remove the turbine frame

Repetitive inspection interval of every location is driven by the minimum reduced

interval

NOTE 1: Dimensions are in inches with millimeters in parentheses.

NOTE 2: For each mount strut:

– If one single crack, measure crack length.

– If multiple cracks, cumulate crack length.

NOTE 3: After TRF removal, cracks may be repairable using the limits provided

in Engine Shop Manual ATA 72-56-01 Inspection 001. Even after

the cracks are repaired, the TRF must still be re-inspected using the

intervals above.

CFM56-5B S/B 72-0850

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

NOTE 4: Three inspection locations on mounts struts (1, 3 and 14):

– Location A: leading edge top end strut, pressure side and suction

side.

– Location B1: the outer casing fillet radius close to rear flange at

mount area (flow path side).

– Location B2: the outer casing fillet radius close to rear flange at

mount area (opposite to the flow path).

F. Installation after the inspection, if the TRF is serviceable:

(1) Installation on wing or in shop:

(a) Install the rear cover and the flame arrestor. Refer to AMM, TASK

72-56-00-400-001 or Engine Shop Manual ATA 72-00-03 INSTALLATION 001.

(2) Installation on wing only:

(a) Install the primary plug assy. Refer to AMM, ATA 78-11-12, TASK

78-11-12-400-041.

(b) Install the primary nozzle assy. Refer to AMM, ATA 78-11-11, TASK

78-11-01-400-041.

G. Quality assurance.

(1) For Eddy Current inspection process:

(a) Record inspection results on the provided inspection sheet report and return

it to CFM field representative. Refer to Figure 10.

(b) All probes, block calibration and materials used for this inspection must be

supplied or validated by CFM.

(c) Keep all inspection records with the permanent record of the Turbine Rear

Frame.

(2) For Fluorescent Penetrant inspection process:

(a) Record inspection results on the provided inspection sheet report and return

it to CFM field representative. Refer to Figure 11.

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

(b) Keep all inspection records with the permanent record of the Turbine Rear

Frame.

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Turbine Rear Frame - Areas to be Inspected

Figure 1

CFM56-5B S/B 72-0850

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Calibration Block

Figure 2

CFM56-5B S/B 72-0850

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Probe 9970-958-574

Figure 3

CFM56-5B S/B 72-0850

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Probe 9970-958-575

Figure 4

CFM56-5B S/B 72-0850

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Probe 9970-958-576

Figure 5

CFM56-5B S/B 72-0850

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Location A

Figure 6

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Location B1

Figure 7

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Location B2

Figure 8

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Defects Length

Figure 9

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Calibration and Inspection Record Form

Figure 10

CFM56-5B S/B 72-0850

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

Fluorescent Penetrant Inspection Record Form

Figure 11

CFM56-5B S/B 72-0850

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ENGINE - LPT Frame Assembly (72-56-00) - Inspection of Turbine Rear Frame on CFM56-5B Engines

4. A - PARTS PROGRESSION CHART

None.

CFM56-5B S/B 72-0850

December 19, 2012 PAGE 25