Method of welding in deep joints

Patent metadata

Field	Value
Publication number	US-2016114433-A1
Application number	US-201514886164-A
Country	US
Kind code	A1
Filing date	Oct 19, 2015
Priority date	Oct 24, 2014
Publication date	Apr 28, 2016
Grant date	—

Abstract

The present relates to a method of welding in deep joints in narrow-gap geometry. The two metallic components are arranged next to each other such that there is nearly a zero gap between the two components. The step of joining two metallic components is performed in two stages, the first stage being a root weld and the second stage being a fill up weld. The root weld is completed at the joining of the two discs starting from a middle portion to a point up to which there is still a zero gap between the two discs. From the point there exists a non-zero gap between the two discs up to an outer portion. The filler gap is filled by fill up welding. During fill up welding, a filler wire is melted along with the two discs by using the first source of energy, and to fill the filler gap along with molten material of the two discs.

First claim

1 . A method of welding for joining two metallic components; the method comprising:
melting the metallic components in a weld region into a molten state to form a weld pool through an energy input by directing at least one first source of energy on the metallic components to join the metallic components, and focusing at least one second source of energy to heat a heating region surrounding the complete weld pool from all sides to reduce cooling rate and extend solidification time of the weld pool.

2 . The method as claimed in claim 1 , wherein the joining two metallic components is performed in two stages, the first stage being a root weld and the second stage being a fill-up weld.

3 . The method as claimed in claim 1 , wherein the metallic components are high-or-low-alloy heat-resistant steel and Nickel-based material.

4 . The method as claimed in claim 1 , wherein the at least one first source of energy and the at least one second source of energy are single or multiple heat source.

5 . The method as claimed in claim 4 , wherein the at least one first source of energy and the at least one second source of energy are beams of energy sources such as, electric arc sources, laser sources, electron beam sources, plasma sources, ultrasonic beams or combination of those.

6 . The method as claimed in claim 5 , wherein the at least one first source of energy is an arc based TIG torch.

7 . The method as claimed in claim 5 , wherein the at least one second source of energy is a moving beam.

8 . The method as claimed in claim 7 , wherein the at least one second source of energy is an oscillating laser beam

9 . The method as claimed in claim 7 , wherein the at least one second source of energy is a weaving laser beam.

10 . The method as claimed in claim 7 , wherein the moving beam is adapted to be focused via multiple heat sources located at multiple locations above the weld pool on at least one position of heating region, surrounding the complete weld-pool.

11 . The method as claimed in claim 10 , wherein the moving beam is adapted to be focused via multiple heat sources located at multiple locations on at least one leading pre-heating position in front of the weld pool and on at least one trailing post-heating position behind the weld pool in the fill-up weld.

12 . The method as claimed in claim 10 , wherein the moving beam is adapted to be focused via multiple heat sources located at multiple locations on heating position towards disc and heating position towards disc besides the weld pool along with the leading pre-heating position in front of the weld pool and the trailing post-heating position behind the weld pool in the root weld.

13 . The method as claimed in claim 12 , wherein heating at heating positions and induce a compressive stress, pulling and keeping both the disc with nearly zero gap pressed to each other towards the weld pool thereby reducing the tolerance limit for zero gap in the root weld.

14 . The method as claimed in claim 7 , wherein the moving beam is power modulated.

15 . The method as claimed in claim 7 , wherein the moving beam is a focused low power laser beam or a defocused high power laser beam to heat the heating region surrounding the complete weld pool from all sides in a narrow gap geometry for all joint depths.

16 . The method as claimed in claim 14 , wherein more power is applied for heating a region of the heating positions, and less power is applied for heating a region of the heating positions.

17 . The method as claimed in claim 1 , wherein the metallic components are in vertical position and the at least one first source of energy is in horizontal position during welding.

18 . The method as claimed in claim 1 , wherein the metallic components are in horizontal position and the at least one first source of energy is in vertical position during welding.

Assignees

• Alstom Technology Ltd

Inventors

• Jaekel Dirk
• Horvath Balint
• Keller Sorin
• Ambrosy Guenter

Classifications

• B23K26/123

  in an atmosphere of particular gases · CPC title

• B23K26/067

  Dividing the beam into multiple beams, e.g. multi-focusing · CPC title

• B23K9/0213

  Narrow gap welding · CPC title

• B23K26/348 Primary

  in combination with arc heating, e.g. tungsten inert gas [TIG], metal inert gas [MIG] or plasma welding · CPC title

• B23K9/16

  making use of shielding gas · CPC title