TASK 70-31-08-310-501 The Procedure To Weld Hardface Material

DMC:V2500-00-70-31-08-00A-627A-D|Issue No:002.00|Issue Date:2018-02-01

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 70-31-08-310-501 The Procedure To Weld Hardface Material

General

This TASK gives the procedure for the argonarc build-up weld of a hardface of cobolt alloy to turbine blades; made of IN100, B1900 and Inconel 713C. This TASK also includes the procedure for the repair of the build-up weld. For related data refer to the SPM TASK 70-31-02-310-501-001.

Argonarc welding equipment such as Millar Syncrowave 300 is to be used. This equipment can be used for DC or AC welding. It includes a contactless starter and a foot-operated remote control adjustment of the weld current. The arc stays stable as low as five amperes. When you weld with AC, the width of the positive or negative half-wave can be changed by 'AC Balance'. This controls the energy transfer to the work through the arc. Use a type HW20 torch with a gas screen.

Preliminary Requirements

Pre-Conditions

NONE

Support Equipment

NameManufacturerPart Number / IdentificationQuantityRemark
Miller Syncrowave 300LOCALMiller Syncrowave 300
TorchLOCALTorch

HW20

Consumables, Materials and Expendables

NameManufacturerPart Number / IdentificationQuantityRemark
CoMat 01-031 ACETONE (CH3)2COLOCALCoMat 01-031
CoMat 03-228 WELDING FILLER WIRED3309CoMat 03-228

Spares

NONE

Safety Requirements

WARNING

IT IS THE RESPONSIBILITY OF THE OPERATOR TO OBTAIN AND OBSERVE THE MANFACTURERS MATERIAL SAFETY DATA SHEETS FOR CONSUMABLE MATERIALS INFORMATION SUCH AS, HAZARDOUS INGREDIENTS, PHYSICAL/CHEMICAL CHARACTERISTICS, FIRE, EXPLOSION, REACTIVITY, HEALTH HAZARD DATA, PRECAUTIONS FOR SAFE HANDLING, USE AND CONTROL MEASURES AND ALSO TO TAKE LOCAL REGULATIONS INTO CONSIDERATION.

Procedure

    1. SUBTASK 70-31-08-110-001 Clean the Surfaces to be Welded

    1. The surfaces to be welded and the adjacent area, must be free of oxides, casting skin, grease, oil and other unwanted material. Clean the surfaces and the filler wire with CoMat 01-031 ACETONE (CH3)2CO before you weld.

    2. SUBTASK 70-31-08-310-001 The Procedure to Weld the Turbine Blades

      1. The inert gas.

      1. A mixture of up to 6.5 percent hydrogen and argon (remainder of the mixture) with a purity of 99.996 percent is to be used as the torch inert gas. The weld area must have a good cover of inert gas. It is recommended that the turbine blades be put in to inert gas boxes flushed with argon.

      2. Set the welding equipment.

      1. The welding is to be done with AC.

      2. Set the current range switch to 'low' and set the current to 30 amperes.

      3. Set the 'AC Balance' switch to between 7 and 8.

      4. Set the gas flow at the torch to approximately 12 l/min. The gas post-flow time is to be approximately ten seconds.

      5. Use a pure tungsten electrode of 0.04in. (1.0 mm) diameter.

      3. CAUTION

        YOU MUST KEEP THE HEAT APPLIED TO A MINIMUM. THIS IS TO PREVENT UNSATISFACTORY DIMENSIONAL CHANGES CAUSED BY SHRINKAGE AND DISTORTION. IF NECESSARY, MORE THAN ONE PASS IS TO BE APPLIED TO GET THE CORRECT BUILD-UP THICKNESS.

        Weld the turbine blades.

        1. When you weld make sure that:

        1. Fusion of the build-up material with the blade is kept to a minimum.

        2. Each layer is immediately cleaned with a stainless steel brush.

        3. Defects you can see must be removed by machining before each pass.

        4. Let the blades become cool before each subsequent pass.

      2. The thickness of the build-up is to be approximately 0.04 to 0.06in. (1.0 to 1.5 mm) more than the necessary dimension.

      3. The build-up material must be fused quickly and flow easily without bubbles.

      4. The beads must be free of gas pores, shrinkage cavities and slag inclusions. The surface must be of sufficient strength and quality to permit more layers to be applied satisfactorily.

      5. To prevent defects or see them sufficiently early carefully monitor the weld pool.

      6. NOTE

        The hardness of the build-up decreases if you do not have the necessary thickness. A thickness of the build-up after finish-machining of at least 0.04in. (1.0mm) is necessary.

        The thickness of the build-up after finish-machining is specified in the applicable repair TASK in the Engine Manual.

      7. Heat treatment of the turbine blades after build-up welding is not necessary.

    3. SUBTASK 70-31-08-320-001 The Procedure to Repair Build-up Welds

      1. If defects occur in the build-up during welding or are found during inspection remove them as follows:

      1. Pores, cavities, inclusions, lack of fusion, notches and cracks are to be mechanically removed and welded again. Refer to Step.

    4. SUBTASK 70-31-08-210-001 Do an Inspection of the Turbine Blades

    1. Do an inspection of the turbine blades. Refer to the applicable inspection TASK in the Engine Manual.

Requirements After Job Completion

Follow-On Conditions

NONE
Change Type:

Update inert gas mixture composition per REA17VC344

Manufacturer Code:D3309
Enterprise Name:MTU MOTOREN-UND-TURBINE UNION MUNCHEN GMBH
BU Name:MTU MOTOREN-UND-TURBINE UNION MUNCHEN GMBH
Street:DACHAUERSTRASSE 665
P.O. Box:80995
City:MUNCHEN 50
Country:GERMANY
Phone Number:49-89-14890
Fax Number:49-89-1502621
Internet:www.mtu.de
Manufacturer Code:LOCAL
Enterprise Name:LOCALLY SUPPLIED
Manufacturer Code:LOCAL
Supply Number:CoMat 01-031
Type:sp01
Supply Short Name:CoMat 01-031 ACETONE (CH3)2CO
Supply Name:CoMat 01-031 ACETONE (CH3)2CO
Specification Groups:
Doc NumberType
OMAT: 150 (RR REF)COMMERCIAL GRADE O-A-51
PMC 9008 (PW REF)COMMERCIAL GRADE O-A-51
JCR-041 (JAEC REF)COMMERCIAL GRADE O-A-51
MTH 169 (98%) (MTU REF)COMMERCIAL GRADE O-A-51
Suppliers:
ManufacturerRemarks
LOCAL
K6835
81348
K3504
U1185
24853
70657
Manufacturer Code:D3309
Supply Number:CoMat 03-228
Type:sp01
Supply Short Name:CoMat 03-228 WELDING FILLER WIRE
Supply Name:CoMat 03-228 WELDING FILLER WIRE
Specification Groups:
Doc NumberType
MTS 1087 PART 1WELDING FILLER WIRE
Suppliers:
ManufacturerRemarks
D3309
Manufacturer Code:LOCAL
Tool Number:Miller Syncrowave 300
Tool Name:Miller Syncrowave 300
Manufacturer Code:LOCAL
Tool Number:Torch
Tool Name:Torch