Tig

Question 1

In tig what is the tungsten melting point?

Answer 1

3370 degrees

Question 2

Name the 5 types of tungsten electrodes

Answer 2

Pure tungsten - aluminium AC - ballpoint

Thorium - radio active

Ceriated - ac/dc - vertex or flat for ac

Lenthaniated - ac/dc vertex or flat for ac

Zirconiated - ac - ballpoint

Question 3

When shaping to a vertex tungsten what are the dimensions?

Answer 3

2-2.5 times diameter of tungsten electrode

Question 4

What is the effect of a steeper vertex angle?

Answer 4

Deeper penetration

Question 5

If you welding aluminium ac tig what tungsten’s and shape point?

Answer 5

Pure tungsten - ballpoint

Zirconiated - ball point

Question 6

What are useable inserts called?

Answer 6

Be boat company or csr

Question 7

What is the primary job of shielding gas?

Answer 7

Keep the air away from

Question 8

What does oxygen and nitrogen cause in tig welding?

Answer 8

Oxygen = oxidisation rust - weakening weld

Nitrogen - porosity and brittleness

Question 9

What is the main choice for gas in tig?

Answer 9

Argon and helium

Argon - heavier than air, lower ionisation so starts the arc well and stable arc

Nitrogen - high thermal conductivity = hotter arc = deeper penetration

Question 10

What is the benefit of adding hydrogen to the mix and how much? In copper and systematic allows?

Answer 10

Increased heat input - add 5%

Question 11

What is the benefit of adding nitrogen and how much?

Answer 11

Back purge only - add 5% - duplex, austentic steels and copper only

Question 12

What is a common range for gas flow?

Answer 12

10-12l per minute

Question 13

What does a gas lease do

Answer 13

Better lamiller flow control