AWS Joint Design & Preparation Flashcards

Which surface condition is MOST likely to cause porosity in a weld if not removed before welding?

Answer: Moisture, oil, rust, or paint on the base metal

Moisture, oil, rust, and paint introduce hydrogen, hydrocarbons, or other gases into the weld pool, causing porosity.

When performing back gouging before welding the second side of a joint, the welder should verify:

Answer: The back gouge has produced a clean, smooth groove that reaches sound weld metal

Back gouging must remove all defects and produce a clean groove extending into sound weld metal before depositing the second-side weld.

Which joint preparation method removes material by using heat and oxygen to produce a narrow, clean cut?

Answer: Oxyfuel cutting

Oxyfuel (oxy-acetylene) cutting uses a preheat flame and an oxygen jet to oxidize and blow away steel, creating the bevel or cut.

For a fillet weld, what does 'leg size' mean?

Answer: The distance from the weld root to the weld toe along one member

The leg size is the distance from the root of the fillet to the toe on each member, and equal-leg fillets have the same leg size on both.

An 'intermittent fillet weld' is used primarily to:

Answer: Reduce the total amount of weld metal deposited while maintaining adequate strength

Intermittent fillet welds reduce the volume of weld metal needed, lowering heat input and cost where continuous welds aren't required.

What is the function of a 'runoff tab' at the end of a weld?

Answer: To allow the welder to terminate the arc beyond the joint, preventing end craters in the weld

Runoff tabs allow the weld to be started and terminated beyond the actual joint, which are later removed to eliminate potential defects from arc craters.