SAW Transmission & Drivetrain Systems 3

Question 1

SAW is being used to hard-surface a transfer case output yoke. The ideal interpass temperature limit is set to prevent:

Accepted Answer

Excessive grain growth in the heat-affected zone

Answer

Allowing excessive interpass temperature causes grain coarsening in the HAZ, reducing toughness and fatigue life of the yoke.

Question 2

Which condition indicates that recovered SAW flux is no longer suitable for reuse on drivetrain components?

Accepted Answer

Presence of fused slag particles

Answer

Fused slag particles in recovered flux cannot melt uniformly and will create inclusions and arc instability in subsequent welds.

Question 3

A planetary gear carrier is rebuilt with multiple SAW passes. Undercut is observed at the weld toes. The primary corrective action is:

Accepted Answer

Reduce arc voltage

Answer

Reducing arc voltage decreases arc width and energy, narrowing the weld bead and eliminating the undercut at the fusion line.

Question 4

For SAW welding of carburized drivetrain components, why is the carburized case typically ground off before welding?

Accepted Answer

To prevent high-carbon weld metal dilution causing brittleness

Answer

The high-carbon carburized layer, if melted into the weld pool, elevates carbon content and promotes crack-susceptible martensite in the deposit.

Question 5

When performing SAW on a large ring gear, the use of run-off tabs at weld end locations primarily prevents:

Accepted Answer

Crater cracks and porosity at the weld termination

Answer

Run-off tabs allow the crater to form and solidify outside the structural weld, preventing the shrinkage cracking and porosity common at weld stops.

(SAW) Submerged Arc Welding Certification Practice Test