API 653 Certification - Practice
Exam - Open Book Questions and
Answers 100% Pass
An insert plate is required for a new 4 NPS nozzle (4.5" O.D.) in the shell. What is the
minimum diameter for this insert?
A. 4.5"
B. 9"
C. 12"
D. 16.5" - ✔✔D. 16.5"
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
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,C. F, H, V
D. All fillets - ✔✔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%. - ✔✔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 - ✔✔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?
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,A. 3"
B. 6"
C. 10"
D. 12" - ✔✔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?
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, A. 12"
B. 24"
C. 25"
D. 40" - ✔✔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?
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Exam - Open Book Questions and
Answers 100% Pass
An insert plate is required for a new 4 NPS nozzle (4.5" O.D.) in the shell. What is the
minimum diameter for this insert?
A. 4.5"
B. 9"
C. 12"
D. 16.5" - ✔✔D. 16.5"
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
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,C. F, H, V
D. All fillets - ✔✔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%. - ✔✔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 - ✔✔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?
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,A. 3"
B. 6"
C. 10"
D. 12" - ✔✔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?
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, A. 12"
B. 24"
C. 25"
D. 40" - ✔✔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?
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