API 653 Certification Open Book Practice
Exam Questions and Verified Answers
Question 1
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
Correct Answer
D. Unlimited
Question 2
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
Correct Answer
C. F, H, V
Page 1 of 199
,Question 3
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".
API 653 sets a limit on the thickness of "t2". In order to provide a 10 year run, what is
the minimum thickness that "t2" can be during this inspection?
A. 0.211"
B. 0.251"
C. 0.281"
D. 0.301"
E. 0.309"
Correct Answer
C. 0.281"
Question 4
WPS (#237) & PQR (#333)
The WPS is not qualified because the:
A. preheat temperature is not supported by the PQR.
B. amp ranges on the WPS are incorrect.
C. rod size is missing on the PQR.
D. root spacing is missing on the PQR.
Correct Answer
A. preheat temperature is not supported by the PQR.
Page 2 of 199
,Question 5
An 8 NPS nozzle will be hot tapped onto a 140' diameter tank. The hot tap is in the
shell two feet above the tank bottom. The tank's 1st course has a nominal thickness of
0.750" and minimum required thickness of 0.642". What is the minimum spacing
between this new nozzle and any existing nozzle?
A. 17.7"
B. 23.2"
C. 25.1"
D. 40"
Correct Answer
C. 25.1"
Question 6
ASME Section VIII had few limitations concerning Brittle Fracture prior to:
A. 1955
B. 1962
C. 1973
D. 1987
Correct Answer
D. 1987
Question 7
A groove weld has an orientation that is 45° inclined from horizontal. The weld cap is
facing straight up. What weld position is this?
A. Flat
B. Horizontal
C. Vertical
D. Overhead
Correct Answer
C. Veritcal
Page 3 of 199
, Question 8
A carbon steel caustic tank has a caustic strength of 30% by weight. Stress relieving of
welds is recommended if:
A. the temperature exceeds 140 °F.
B. the temperature is lower than 32 °F.
C. the material toughness is below 15 ft-lbs.
D. low strength steels are used.
Correct Answer
A. the temperature exceeds 140 °F.
Question 9
Determine the maximum edge settlement allowed in a 120' tank. The settlement is
perpendicular to the bottom plate welds and "breaks" 4' from the shell.
A. 1.5"
B. 4.5"
C. 5.5"
D. 18"
Correct Answer
C. 5.5"
Question 10
A replacement tank bottom uses 3/8" plates that will be fillet-welded. What is the
minimum size of fillet weld allowed for these tank bottom welds?
A. 3/16"
B. 1/4"
C. 3/8"
D. 1/2"
Correct Answer
C. 3/8"
Page 4 of 199
Exam Questions and Verified Answers
Question 1
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
Correct Answer
D. Unlimited
Question 2
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
Correct Answer
C. F, H, V
Page 1 of 199
,Question 3
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".
API 653 sets a limit on the thickness of "t2". In order to provide a 10 year run, what is
the minimum thickness that "t2" can be during this inspection?
A. 0.211"
B. 0.251"
C. 0.281"
D. 0.301"
E. 0.309"
Correct Answer
C. 0.281"
Question 4
WPS (#237) & PQR (#333)
The WPS is not qualified because the:
A. preheat temperature is not supported by the PQR.
B. amp ranges on the WPS are incorrect.
C. rod size is missing on the PQR.
D. root spacing is missing on the PQR.
Correct Answer
A. preheat temperature is not supported by the PQR.
Page 2 of 199
,Question 5
An 8 NPS nozzle will be hot tapped onto a 140' diameter tank. The hot tap is in the
shell two feet above the tank bottom. The tank's 1st course has a nominal thickness of
0.750" and minimum required thickness of 0.642". What is the minimum spacing
between this new nozzle and any existing nozzle?
A. 17.7"
B. 23.2"
C. 25.1"
D. 40"
Correct Answer
C. 25.1"
Question 6
ASME Section VIII had few limitations concerning Brittle Fracture prior to:
A. 1955
B. 1962
C. 1973
D. 1987
Correct Answer
D. 1987
Question 7
A groove weld has an orientation that is 45° inclined from horizontal. The weld cap is
facing straight up. What weld position is this?
A. Flat
B. Horizontal
C. Vertical
D. Overhead
Correct Answer
C. Veritcal
Page 3 of 199
, Question 8
A carbon steel caustic tank has a caustic strength of 30% by weight. Stress relieving of
welds is recommended if:
A. the temperature exceeds 140 °F.
B. the temperature is lower than 32 °F.
C. the material toughness is below 15 ft-lbs.
D. low strength steels are used.
Correct Answer
A. the temperature exceeds 140 °F.
Question 9
Determine the maximum edge settlement allowed in a 120' tank. The settlement is
perpendicular to the bottom plate welds and "breaks" 4' from the shell.
A. 1.5"
B. 4.5"
C. 5.5"
D. 18"
Correct Answer
C. 5.5"
Question 10
A replacement tank bottom uses 3/8" plates that will be fillet-welded. What is the
minimum size of fillet weld allowed for these tank bottom welds?
A. 3/16"
B. 1/4"
C. 3/8"
D. 1/2"
Correct Answer
C. 3/8"
Page 4 of 199
