IMM Welding & Fabrication

Question 1

Which welding process uses a consumable electrode covered with a flux coating?

Accepted Answer

SMAW (Stick welding)

Answer

SMAW (Shielded Metal Arc Welding) uses a flux-coated stick electrode that melts to shield the weld pool from atmospheric contamination.

Question 2

What is the primary purpose of preheating steel before welding?

Accepted Answer

To reduce the risk of hydrogen-induced cracking

Answer

Preheating slows the cooling rate and allows hydrogen to diffuse out of the weld zone, preventing hydrogen-induced (cold) cracking.

Question 3

Which shielding gas is standard for GTAW (TIG) welding of stainless steel?

Accepted Answer

100% Argon

Answer

Pure argon is the standard shielding gas for TIG welding stainless steel because it is inert and provides excellent arc stability without oxidizing the material.

Question 4

What does 'duty cycle' mean when referring to welding equipment?

Accepted Answer

The percentage of a 10-minute period a machine can weld at a rated output without overheating

Answer

Duty cycle is the percentage of a 10-minute period that a welding machine can continuously operate at a given output level before it must cool down.

Question 5

Which weld defect is a groove melted into the base metal along the toe of the weld that is left unfilled by weld metal?

Accepted Answer

Undercut

Answer

Undercut is a groove eroded into the base metal along the weld toe, reducing the effective cross-sectional area and creating a stress concentration.

IMM - Industrial Maintenance Mechanic Certified Practice Test

IMM - Industrial Maintenance Mechanic Certified Practice Test

IMM Welding & Fabrication