AWS Joint Design & Preparation 2

Question 1

What is the primary advantage of a double-V groove joint over a single-V groove joint for welding thick plates?

Accepted Answer

Reduces total weld metal volume and distortion by welding from both sides

Answer

A double-V groove allows deposition of approximately half the weld metal of a single-V groove for the same plate thickness, reducing filler consumption, heat input, and angular distortion by balancing shrinkage forces from both sides.

Question 2

Per AWS D1.1, what is the maximum allowable root face (land) dimension for a prequalified single-V groove weld joint?

Accepted Answer

3 mm (⅛ in.)

Answer

AWS D1.1 prequalified joint details specify a maximum root face (land) of 3 mm (⅛ in.) for single-V groove joints to ensure adequate root penetration while controlling burn-through.

Question 3

What is the function of a backing strip (backing bar) in a groove weld joint?

Accepted Answer

Support the root pass to achieve complete joint penetration without requiring a welder to weld in difficult root access positions

Answer

A backing strip supports the molten root pass, enabling full penetration to be achieved without the precise control required for open-root welding, particularly in restricted-access or single-sided weld situations.

Question 4

In joint design, what is the purpose of a weld access hole (rat hole) cut at the end of a beam web at a moment connection?

Accepted Answer

Provide access for the welder to make a complete penetration weld at the beam flange without depositing weld metal in areas of high stress triaxiality

Answer

Weld access holes remove the web material adjacent to the flange-to-column connection, eliminating the triaxial stress state at the web-flange junction that is prone to lamellar tearing and weld cracking in seismically loaded moment frames.

Question 5

What is the minimum base metal thickness for which a fillet weld is permitted as the sole means of joining two plates per AWS D1.1 prequalified requirements?

Accepted Answer

There is no minimum thickness for fillet welds, but minimum size requirements are based on the thicker member

Answer

AWS D1.1 does not prohibit fillet welds based on base metal thickness per se, but Table 5.8 specifies minimum fillet weld sizes based on the thicker part being joined to ensure adequate fusion and avoid rapid quenching of the root area.

AWS Practice Test

AWS Practice Test

AWS Joint Design & Preparation 2