AWS Joint Design & Preparation 5 — Questions and Answers
Question 1: Which AWS joint type is formed when two members are joined at an angle other than 90°?
- T-joint
- Corner joint
- Oblique joint (Correct answer)
- Edge joint
Correct answer: Oblique joint
An oblique joint is formed when two members meet at an angle other than a right angle, requiring special consideration in groove design.
Question 2: What is the recommended maximum root face dimension for a SMAW groove weld to ensure complete root fusion?
- 3/4 inch
- 1/2 inch
- 1/8 inch (Correct answer)
- 1/4 inch
Correct answer: 1/8 inch
AWS recommends a root face of approximately 1/8 inch (3 mm) for SMAW to ensure the electrode arc can fuse through to the back of the joint.
Question 3: When preparing a J-groove joint, what is the main advantage over a V-groove joint for thick plate?
- J-groove requires a larger groove angle for access
- J-groove requires less weld metal due to its curved groove face profile (Correct answer)
- J-groove eliminates the need for any root opening
- J-groove can only be used with GMAW processes
Correct answer: J-groove requires less weld metal due to its curved groove face profile
The curved radius at the bottom of a J-groove reduces the cross-sectional area of the weld groove, requiring significantly less filler metal than a V-groove in thick plate.
Question 4: In AWS D1.1 Structural Welding Code, what is the minimum preheat temperature required before making joint preparations on hardenable alloy steels?
- No preheat is required for joint preparation
- It depends on the carbon equivalent and material thickness (Correct answer)
- Always 400°F regardless of thickness
- Always 200°F for all alloy steels
Correct answer: It depends on the carbon equivalent and material thickness
AWS D1.1 preheat requirements for hardenable steels depend on carbon equivalent (CE) and material thickness, not a single fixed temperature.
Question 5: What is the purpose of a 'runoff tab' used during joint preparation and welding of butt joints?
- To preheat the joint ends before welding
- To extend the weld beyond the base metal ends to ensure full-size weld at the joint ends (Correct answer)
- To measure the groove angle during fit-up
- To act as a heat sink preventing distortion at joint ends
Correct answer: To extend the weld beyond the base metal ends to ensure full-size weld at the joint ends
Runoff tabs are temporary extensions welded at the ends of a joint so the weld can start and terminate at full cross-section, avoiding craters and incomplete fusion at the edges.
Question 6: Which of the following groove weld joint preparations provides the best accessibility for the welding electrode in a narrow deep groove?
- Square groove
- V-groove
- U-groove (Correct answer)
- Bevel groove
Correct answer: U-groove
A U-groove's curved profile provides better electrode accessibility in deep, narrow joints compared to V or bevel grooves, which become very narrow at depth.
Question 7: When fitting up a corner joint for full-penetration welding, what preparation is typically required on the inner member?
- No preparation needed; fillet weld is sufficient
- A bevel or groove preparation to allow access to the root (Correct answer)
- A square cut with maximum root opening of 1 inch
- Grinding the corner to a radius before welding
Correct answer: A bevel or groove preparation to allow access to the root
For full-penetration corner joints, the inner member requires a bevel or groove preparation to allow the weld to penetrate to the full thickness of the joint.
AWS Joint Design & Preparation 5
Which AWS joint type is formed when two members are joined at an angle other than 90°?