TASK 70-31-02-310-501-010 Argonarc Welding Repairs - The Procedure To Weld Nimonic 90 Alloy

DMC:V2500-00-70-31-02-09A-627A-D|Issue No:001.00|Issue Date:2013-03-20

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 70-31-02-310-501-010 Argonarc Welding Repairs - The Procedure To Weld Nimonic 90 Alloy

General

Nimonic 90 is a nickel chromium alloy of the precipitation hardening type. It is resistant to creep and is very strong at high temperatures.

The weldability of this alloy depends on its heat treatment condition. The alloy is easily welded in the solution treated and air or water quenched condition. But Nimonic 90 is usually in the fully aged condition and not easy to weld. It also cracks easily in this condition.

Refer to the SPM TASK 70-31-02-310-501-001 for other related TASKS.

Preliminary Requirements

Pre-Conditions

NONE

Support Equipment

NONE

Consumables, Materials and Expendables

NONE

Spares

NONE

Safety Requirements

WARNING

IT IS THE RESPONSIBILITY OF THE OPERATOR TO OBTAIN AND OBSERVE THE MANUFACTURER'S MATERIAL SAFETY DATA SHEETS FOR CONSUMABLE MATERIALS. THESE CONTAIN 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 70-31-02-310-020 Preparation of the Surface

    1. Surface scale will occur if this alloy is heat treated or operated at temperatures of more than 1292 deg F (700 deg C).

    2. Remove all scale and oxidation from the surfaces before you weld. This can be done mechanically or with abrasive blasting.

    2. SUBTASK 70-31-02-310-021 The Procedure to Weld Nimonic 90

    1. Automatic current slope-out at the end of the weld run is necessary to prevent crater cracks.

    2. It is important to weld this material carefully to decrease the quantity of cracks which can occur in the heat affected zone because of different temperatures.

    3. Tungsten Inert Gas welding is recommended for this material.

    3. SUBTASK 70-31-02-370-008 The Heat Treatment of Nimonic 90

    1. For good results it is recommended to solution heat treat again before you weld. Do this only if the component is resistant to distortion.

    2. Heat treatment instructions are given in the applicable Repair. Also refer to the SPM TASK 70-31-02-310-501-001 and SPM TASK 70-31-02-310-501-004.

Requirements After Job Completion

Follow-On Conditions

NONE