Friction stir welding: method and device for filling a hole at the end of welding or for repairing a welding defect

Patent metadata

Field	Value
Publication number	US-9815152-B2
Application number	US-201615051374-A
Country	US
Kind code	B2
Filing date	Feb 23, 2016
Priority date	Feb 26, 2015
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

A method for repairing a defect affecting a weld. A sheet of filler metal is placed on the surface of the welded part, next to the region of the defect. The sheet is locally welded to the welded part in the region of the defect using a friction stir welding tool having a retractable welding pin. The welded part and the sheet are separated such that the filler metal amalgamated with the metal of the welded part remains in position. The local welding operation includes successively performing the following: setting the welding tool into rotation and putting it under pressure; inserting the pin to a small distance from the anvil while maintaining or increasing the pressure on the shoulder of the welding tool; progressively retracting the pin while maintaining or increasing the pressure on the shoulder; and stopping the pressure on the shoulder when the retractable pin has been retracted.

First claim

The invention claimed is:

1. A method for reworking a defect affecting a weld, comprising the steps of:
placing a sheet of a filler metal in a region of the defect, the sheet of the filler metal being placed on a surface of a welded part next to the region of the defect;
locally welding the sheet of the filler metal to the welded part, the welding being carried out in the region of the defect with the aid of a friction stir welding tool comprising a retractable welding pin; and
separating the welded part and the sheet of the filler metal to leave the filler metal in place in a manner amalgamated by welding with a metal of the welded part;
wherein the step of separating is performed at the end of the locally welding step, by imparting a movement on the sheet of the filler metal in a plane of the welded part before a rotation of the friction stir welding tool stops.

2. The method according to claim 1 , wherein the step of locally welding comprises the following successive steps of:
setting the friction stir welding tool into rotation and putting the friction stir welding tool under a pressure;
inserting the retractable welding pin progressively into the welded part while maintaining or increasing the pressure on a shoulder of the friction stir welding tool;
progressively retracting the retractable welding pin while maintaining or increasing the pressure on the shoulder of the friction stir welding tool;
stopping the pressure on the shoulder of the friction stir welding tool upon withdrawal of the retractable welding pin from a top of the welded part.

3. The method according to claim 2 , wherein the step of inserting the retractable welding pin is accompanied by the step of inserting the shoulder of the friction stir welding tool at a movement rate slower than that of the retractable welding pin.

4. The method according to claim 2 , wherein the step of inserting the retractable welding pin is accompanied by a continuous orbital movement of the retractable welding pin.

5. The method according to claim 1 , further comprising the step of renewing a surface state of the welded part in the region of the defect.

Assignees

• Airbus Group Sas
• Airbus

Inventors

• Foucher Gilles
• Marie François
• Aliaga Daniel

Classifications

• B23K20/1265

  Non-butt welded joints, e.g. overlap-joints, T-joints or spot welds · CPC title

• B23P6/00 Primary

  Restoring or reconditioning objects (straightening or restoring form of sheet metal, metal rods, metal tubes, metal profiles, or specific articles made therefrom B21D1/00, B21D3/00; repairing defective or damaged objects by casting techniques B22D19/10) · CPC title

• B23K20/124

  at the beginning or at the end of a weld · CPC title

• B23K20/122 Primary

  using a non-consumable tool, e.g. friction stir welding · CPC title

• B23K20/128

  making use of additional material · CPC title