Alternative welding

Question 1

Resistance welding

Answer 1

A group of fusion welding, high temperature is generated by electrical resistance to current flow at the junction being welded

Question 2

Resistance Spot Welding

Answer 2

Typically sheet metal, two opposing electrodes, apply pressure to squeeze parts between copper electrode, up to 3 mm thick sheet

Question 3

Resistance Seam Welding

Answer 3

Uses rotating copper wheel electrodes to make a series of overlapping spot welds, produce liquid/air tight joints, fast

Question 4

Plasma Arc Welding

Answer 4

Tungsten electrode contained in a nozzle, focuses high velocity stream of inert gas (argon) into arc region to form high velocity, super hot plasma arc stream, typically CNC controlled

Question 5

Benefits of Resistance welding

Answer 5

Advantages:
- No filler material needed
- High production rates
- Can be used by automations (robots)
Disadvantages:
-Moderate to high equipment cost
-Limited to lap or butt joints

Question 6

Benefits of Plasma Arc Welding (Advantages and Disadvantages)

Answer 6

Advantages:
Excellent weld quality, better penetration that other arc welding, high travel speeds, can be used to weld almost any metal
Disadvantages:
High cost, water cooled handpick, large torch size restricts access to some welds.

Question 7

Oxyacetylene welding consumables

Answer 7

Steel wire - For thin steel parts (fusion)
Brazing rod - For Steel, cast iron (Diffusion)
Easyflow/Silver - Silver/Copper alloy for brazing copper, brass, steel, stainless steel (Diffusion)
Silfos/Silvaloy - Copper(Plumbing), Brass(Diffusion)
Aluminium rod - Aluminium (not common). Prefer mig and tig

Question 8

Laser Beam welding

Answer 8

Penetration up to 19 mm in steel, no filler required, low heat input and low distortion, doesn’t require a vacuum

Question 9

Limitation of laser beam welding

Answer 9

Joint tracking is critical, not portable, copper and aluminium are reflective and hard to laser weld

Question 10

Electron Beam Welding