API 653 RECERTIFICATION STUDY GUIDE
2026 QUESTIONS WITH SOLUTIONS
GRADED A+
⩥ A welder is qualified on a plate in the 3G position. The welder is
qualified for what fillet weld position(s)?
A. None
B. F, H
C. F, H, V
D. All fillets. Answer: C. F, H, V
⩥ When must a shim be placed under an Image Quality Indicator?
A. When the area of interest is darker.
B. When the area of interest is darker by more than 15%.
C. When the area of interest is lighter
D. When the area of interest is lighter by more than 15%. Answer: D.
When the area of interest is lighter by more than 15%.
⩥ A welder passes a qualification test using a 3 NPS pipe with a groove
weld. What is the maximum pipe diameter that the welder is now
qualified to weld?
,A. 2-7/8"
B. 4"
C. 8"
D. Unlimited Answer: D. Unlimited
⩥ A portion of a 1/2" thick shell plate is replaced. What is the closest
distance allowed between this plate and the adjacent vertical weld?
A. 3"
B. 6"
C. 10"
D. 12" Answer: B. 6"
⩥ Tank Number: T-100
Diameter: 114'
Specific Gravity: 0.9
Plate Material: A-283 gr C
Shell Corrosion Rate: 0.003"/yr
Allowable Liquid Height: 40'
Construction Code: API 650 4th Edition
, A corroded area is found 3' from the bottom and 4" from the nearest
weld. The lowest reading in the locally corroded area is 0.368".
What is the critical length "L" in the corroded area?
A. 12"
B. 24"
C. 25"
D. 40" Answer: B. 24"
⩥ Tank Number: T-100
Diameter: 114'
Specific Gravity: 0.9
Plate Material: A-283 gr C
Shell Corrosion Rate: 0.003"/yr
Allowable Liquid Height: 40'
Construction Code: API 650 4th Edition
A corroded area is found 3' from the bottom and 4" from the nearest
weld. The lowest reading in the locally corroded area is 0.368".
What is the required thickness "tmin" in this corroded area?
2026 QUESTIONS WITH SOLUTIONS
GRADED A+
⩥ A welder is qualified on a plate in the 3G position. The welder is
qualified for what fillet weld position(s)?
A. None
B. F, H
C. F, H, V
D. All fillets. Answer: C. F, H, V
⩥ When must a shim be placed under an Image Quality Indicator?
A. When the area of interest is darker.
B. When the area of interest is darker by more than 15%.
C. When the area of interest is lighter
D. When the area of interest is lighter by more than 15%. Answer: D.
When the area of interest is lighter by more than 15%.
⩥ A welder passes a qualification test using a 3 NPS pipe with a groove
weld. What is the maximum pipe diameter that the welder is now
qualified to weld?
,A. 2-7/8"
B. 4"
C. 8"
D. Unlimited Answer: D. Unlimited
⩥ A portion of a 1/2" thick shell plate is replaced. What is the closest
distance allowed between this plate and the adjacent vertical weld?
A. 3"
B. 6"
C. 10"
D. 12" Answer: B. 6"
⩥ Tank Number: T-100
Diameter: 114'
Specific Gravity: 0.9
Plate Material: A-283 gr C
Shell Corrosion Rate: 0.003"/yr
Allowable Liquid Height: 40'
Construction Code: API 650 4th Edition
, A corroded area is found 3' from the bottom and 4" from the nearest
weld. The lowest reading in the locally corroded area is 0.368".
What is the critical length "L" in the corroded area?
A. 12"
B. 24"
C. 25"
D. 40" Answer: B. 24"
⩥ Tank Number: T-100
Diameter: 114'
Specific Gravity: 0.9
Plate Material: A-283 gr C
Shell Corrosion Rate: 0.003"/yr
Allowable Liquid Height: 40'
Construction Code: API 650 4th Edition
A corroded area is found 3' from the bottom and 4" from the nearest
weld. The lowest reading in the locally corroded area is 0.368".
What is the required thickness "tmin" in this corroded area?
