AWS AWS D1.1 Structural Welding Code 4 — Questions and Answers
Question 1: According to AWS D1.1, what is the minimum preheat temperature required for ASTM A36 steel with thickness over 1.5 inches when using SMAW with low-hydrogen electrodes?
- 50°F (10°C)
- 150°F (65°C) (Correct answer)
- 225°F (107°C)
- 300°F (149°C)
Correct answer: 150°F (65°C)
AWS D1.1 Table 4.2 requires a minimum preheat of 150°F (65°C) for A36 steel over 1.5 inches thick welded with low-hydrogen processes.
Question 2: Under AWS D1.1, which discontinuity type is ALWAYS rejectable regardless of size in cyclically loaded structures?
- Porosity
- Undercut
- Cracks (Correct answer)
- Overlap
Correct answer: Cracks
AWS D1.1 prohibits cracks of any size in welds for both statically and cyclically loaded structures, making them always rejectable.
Question 3: What does AWS D1.1 specify as the maximum interpass temperature for quenched-and-tempered steels such as ASTM A514?
- 250°F (121°C)
- 400°F (204°C) (Correct answer)
- 550°F (288°C)
- 700°F (371°C)
Correct answer: 400°F (204°C)
AWS D1.1 limits interpass temperature to 400°F (204°C) for quenched-and-tempered steels to avoid degrading their mechanical properties.
Question 4: In AWS D1.1, a Welding Procedure Specification (WPS) must be qualified by testing when it is classified as a:
- Prequalified WPS meeting all code conditions
- Non-prequalified WPS or one with essential variable changes (Correct answer)
- WPS used only for tack welds
- WPS for FCAW-G on carbon steel
Correct answer: Non-prequalified WPS or one with essential variable changes
WPSs that do not meet all prequalified conditions or involve changes to essential variables must be qualified by test per AWS D1.1 Clause 4.
Question 5: According to AWS D1.1, what is the minimum fillet weld size permitted for a base metal thickness of 3/4 inch (19 mm)?
- 1/8 in (3 mm)
- 3/16 in (5 mm)
- 1/4 in (6 mm) (Correct answer)
- 5/16 in (8 mm)
Correct answer: 1/4 in (6 mm)
AWS D1.1 Table 8.8 requires a minimum fillet weld size of 1/4 in (6 mm) for base metal thickness from 1/2 in to 3/4 in.
Question 6: When performing ultrasonic testing (UT) per AWS D1.1, the reference calibration block must be made from material with an acoustic velocity within what tolerance of the production weld material?
- ±1%
- ±5% (Correct answer)
- ±10%
- ±15%
Correct answer: ±5%
AWS D1.1 Annex S requires UT calibration blocks to have acoustic velocity within ±5% of the production material to ensure accurate flaw sizing.
Question 7: Under AWS D1.1, which of the following electrode classifications is considered low-hydrogen for SMAW?
- E6010
- E6013
- E7018 (Correct answer)
- E7024
Correct answer: E7018
E7018 is a low-hydrogen electrode (designated by the '8' suffix indicating low-hydrogen, iron powder covering), whereas E6010, E6013, and E7024 are not low-hydrogen.
AWS AWS D1.1 Structural Welding Code 4
According to AWS D1.1, what is the minimum preheat temperature required for ASTM A36 steel with thickness over 1.5 inches when using SMAW with low-hydrogen electrodes?