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 70-31-02-310-501-016 Argonarc Welding Repairs - The Procedure To Weld Titanium Alloys
General
The primary problem when titanium alloy is fusion welded is that contamination occurs very easily. This contamination is usually because of oxygen, nitrogen and water vapor.
Sufficient argon coverage is very important and all welding fixtures and torches must permit good coverage.
To prevent air contamination to the argon supply, flexible connections in the supply hose must be kept to a minimum. They must also be kept as short as possible.
Refer to the SPM TASK 70-31-02-310-501-001 for related TASKS.
When the hot weld metal goes out of the torch protection zone, the temperature is sufficiently high for the weld metal to collect contamination from oxygen and nitrogen. Trailing shrouds, which give argon coverage some distance behind the arc, prevent this. IAE recommends to weld a test piece before you do the Repair to make sure there is sufficient argon coverage. The light surface contamination seen as a light straw color is permitted, for further details refer to TASK 70-31-02-310-501-001, SUBTASK 70-31-02-220-002.
An alternative to open shop welding is to use an argon filled cabinet or dome with rubber glove openings. Regular checks on the argon coverage can be done if you weld unwanted pieces of titanium and examine them for contamination, refer to TASK 70-31-02-310-501-001, SUBTASK 70-31-02-220-002.
Preliminary Requirements
Pre-Conditions
NONESupport Equipment
NONEConsumables, Materials and Expendables
| Name | Manufacturer | Part Number / Identification | Quantity | Remark |
|---|---|---|---|---|
| CoMat 01-031 ACETONE (CH3)2CO | LOCAL | CoMat 01-031 | ||
| CoMat 01-076 METHYL ETHYL KETONE | LOCAL | CoMat 01-076 | ||
| CoMat 01-124 ISOPROPYL ALCOHOL | LOCAL | CoMat 01-124 |
Spares
NONESafety Requirements
WARNING
Procedure
WARNING
YOU MUST NOT SMOKE WHEN YOU USE THE CLEANING FLUID TO REMOVE THE GREASE AS THE VAPOR WILL CHEMICALLY DIVIDE TO GIVE OUT A VERY POISONOUS GAS.YOU MUST HAVE ON APPROVED EYE PROTECTION, CHEMICALLY RESISTANT CLOTHING AND GLOVES WHEN YOU USE THE CLEANING FLUID TO REMOVE THE GREASE.Clean each of the surfaces to be welded with a clean lint-free cloth made moist with CoMat 01-031 ACETONE (CH3)2CO, CoMat 01-076 METHYL ETHYL KETONE, CoMat 01-124 ISOPROPYL ALCOHOL. Make sure the weld area is not subsequently touched.
SUBTASK 70-31-02-310-032 Preparation of the Surface
Welding must be done with DC equipment as specified in SPM TASK 70-31-02-310-501-001.
The color of the weld to be repaired must be within the acceptable standard. Refer to TASK 70-31-02-310-501-001, SUBTASK 70-31-02-220-002.
SUBTASK 70-31-02-310-033 The Procedure to Weld Titanium Alloy
Most titanium alloys do not have to be post weld heat treated. Heat treatment instructions will be given in the applicable Repair. Also refer to the SPM TASK 70-31-02-310-501-004.
SUBTASK 70-31-02-370-014 The Heat Treatment of Titanium Alloy