API 653 EXAM 1 QUESTIONS AND ANSWERS
2024
Who Determines to use RBI methodologies? - ANSWERS Owner/Operator
RBI Document - API Code? - ANSWERS API 580
What are the two factors of Risk? - ANSWERS Consequence of failure and Likelihood
of Failure
RBI Assessments must be thoroughly___________? - ANSWERS Documented
Who conducts an RBI Assessment? - ANSWERS Team of Knowledgeable of RBI
Principles
RBI Assessments shall be repeated at least every ______ Years? - ANSWERS 10
years
Two Primary Factors of Consequence of Failure are? - ANSWERS Product Type and
Volume
Minimum thickness of a NEW tank bottom plate? - ANSWERS 0.250"
Minimum thickness of an existing tank bottom plate without coating or
detection/contain leak? - ANSWERS 0.100"
Minimum thickness of an existing tank bottom plate with a thick reinforced coating (>50
mils) - ANSWERS 0.050"
Minimum thickness of an existing tank bottom plate with detection and contain a leak?
- ANSWERS 0.050"
Typical Shell Floor plates are welded how? - ANSWERS Lap Welded
Annular Shell floor plates are welded how? - ANSWERS Butt Welded
Minimum size of a new bottom fillet weld? - ANSWERS Full fillet
Three-plate Laps must be ______ inches from everything else? - ANSWERS 12"
What is the minimum radial width of an annular plate? (Shell to nearest Lap Weld) -
ANSWERS 24"
, What is the minimum width of a bottom plate extension on outside of shell? (Answer
for both New & Existing) - ANSWERS New - 2", Existing - 3/8"
What is the minimum thickness allowed of an existing bottom plate extension at the
shell-bottom weld? - ANSWERS 0.100"
Most existing tank bottoms are inspected with _________. Areas of concern found are
normally checked with ____________. - ANSWERS MFL, UT
What is the width of the Critical Zone on existing tank bottoms? - ANSWERS 3"
What is the minimum thickness of an existing tank bottom in a Critical Zone? -
ANSWERS Less of 1/2 of original floor or. 1/2 T-min of 1st Shell Course, Typically it is
0.125"
What is the required length of RT on a Vert or Horizontal Tank Weld? - ANSWERS 6"
What is the required length of RT at Tank Intersections at:
Vertical? Horizontal? - ANSWERS 3" on Verts weld seam and 2" on each side of verts
If there is a weld defect in a spot RT, how many RTs are required? - ANSWERS 2
unless there is 3" of good weld beyond the defect.
Method for RT: RT is shot to____________? - ANSWERS ASME Section V
What requirements are needed for Personnel to shoot an RT on a Tank? - ANSWERS
ASNT SNT-TC-1A
Acceptance Criteria for RT on a tank is? - ANSWERS ASME Section VIII
A rounded indication is one that's length is less than or equal to ___________ times its
width - ANSWERS 3 times
100% of new vertical welds should be RT'd if the shell thickness is greater than
_______________? - ANSWERS 1"
How many RT's are needed when a rectangular insert plate is installed in the shell? -
ANSWERS 6 RTs
Which RT exposure technique is preferred? - ANSWERS Single Wall
What is the minimum # of RTs required for a nozzle/pipe butt weld being completed
using a double-wall technique with a single view? - ANSWERS 3 - 120 degrees apart
, What is the minimum # of RTs required for a nozzle/pipe butt weld being RT'd using a
double wall technique with a double-wall view? - ANSWERS 2- 0 degree and 90
degree
The maximum pipe size when RT'ing a pipe using docuble-wall technique with a
double-wall view is _________? - ANSWERS NPS 3 or 3.5" OD.
Wire IQI's are placed on the weld with the wires ____________ to the weld? -
ANSWERS Perpendicular
Hole Type IQI's are normally placed ___________ to the weld. - ANSWERS Adjacent
If a hole-type IQI is used; the ________ hole must be seen in the RT. - ANSWERS 2T
hole
The preferred location for the IQI is on the ________ side? - ANSWERS Source Side
If an IQI is placed on the film side, a lead letter __________ should be placed near the
IQI. - ANSWERS F
If a shim is used under a hole-type IQI, then ________ side of the IQI should be
distinctly visible in the RT? - ANSWERS 3 side
When using a gamma radiation source, the film density limits are_________ for the IQI
and weld? - ANSWERS 2.0 to 4.0
Densitometers should be calibrated how often? - ANSWERS 90 days
What is an indication of unacceptable backscatter when taking an RT? - ANSWERS
Faint light B
Iridium 192 is used on wall thicknesses of ____________? - ANSWERS O.25" to 3.0"
Cobalt 60 is used on wall thicknesses of ______________? - ANSWERS 1.5" to 7"
When qualifying a welder with RT, what 3 indications are always unacceptable? -
ANSWERS Cracks, Lack of Fusion and Lack of Penatration
When can RT not be used to qualify a welder? What Process? - ANSWERS GMAW -
SC
How much RT is required to qualify a welder on a coupon? 1st Production weld? -
ANSWERS 6", 6"
How much RT is required to qualify a welding operator on a coupon? 1st production
Weld? - ANSWERS 6", 36"
2024
Who Determines to use RBI methodologies? - ANSWERS Owner/Operator
RBI Document - API Code? - ANSWERS API 580
What are the two factors of Risk? - ANSWERS Consequence of failure and Likelihood
of Failure
RBI Assessments must be thoroughly___________? - ANSWERS Documented
Who conducts an RBI Assessment? - ANSWERS Team of Knowledgeable of RBI
Principles
RBI Assessments shall be repeated at least every ______ Years? - ANSWERS 10
years
Two Primary Factors of Consequence of Failure are? - ANSWERS Product Type and
Volume
Minimum thickness of a NEW tank bottom plate? - ANSWERS 0.250"
Minimum thickness of an existing tank bottom plate without coating or
detection/contain leak? - ANSWERS 0.100"
Minimum thickness of an existing tank bottom plate with a thick reinforced coating (>50
mils) - ANSWERS 0.050"
Minimum thickness of an existing tank bottom plate with detection and contain a leak?
- ANSWERS 0.050"
Typical Shell Floor plates are welded how? - ANSWERS Lap Welded
Annular Shell floor plates are welded how? - ANSWERS Butt Welded
Minimum size of a new bottom fillet weld? - ANSWERS Full fillet
Three-plate Laps must be ______ inches from everything else? - ANSWERS 12"
What is the minimum radial width of an annular plate? (Shell to nearest Lap Weld) -
ANSWERS 24"
, What is the minimum width of a bottom plate extension on outside of shell? (Answer
for both New & Existing) - ANSWERS New - 2", Existing - 3/8"
What is the minimum thickness allowed of an existing bottom plate extension at the
shell-bottom weld? - ANSWERS 0.100"
Most existing tank bottoms are inspected with _________. Areas of concern found are
normally checked with ____________. - ANSWERS MFL, UT
What is the width of the Critical Zone on existing tank bottoms? - ANSWERS 3"
What is the minimum thickness of an existing tank bottom in a Critical Zone? -
ANSWERS Less of 1/2 of original floor or. 1/2 T-min of 1st Shell Course, Typically it is
0.125"
What is the required length of RT on a Vert or Horizontal Tank Weld? - ANSWERS 6"
What is the required length of RT at Tank Intersections at:
Vertical? Horizontal? - ANSWERS 3" on Verts weld seam and 2" on each side of verts
If there is a weld defect in a spot RT, how many RTs are required? - ANSWERS 2
unless there is 3" of good weld beyond the defect.
Method for RT: RT is shot to____________? - ANSWERS ASME Section V
What requirements are needed for Personnel to shoot an RT on a Tank? - ANSWERS
ASNT SNT-TC-1A
Acceptance Criteria for RT on a tank is? - ANSWERS ASME Section VIII
A rounded indication is one that's length is less than or equal to ___________ times its
width - ANSWERS 3 times
100% of new vertical welds should be RT'd if the shell thickness is greater than
_______________? - ANSWERS 1"
How many RT's are needed when a rectangular insert plate is installed in the shell? -
ANSWERS 6 RTs
Which RT exposure technique is preferred? - ANSWERS Single Wall
What is the minimum # of RTs required for a nozzle/pipe butt weld being completed
using a double-wall technique with a single view? - ANSWERS 3 - 120 degrees apart
, What is the minimum # of RTs required for a nozzle/pipe butt weld being RT'd using a
double wall technique with a double-wall view? - ANSWERS 2- 0 degree and 90
degree
The maximum pipe size when RT'ing a pipe using docuble-wall technique with a
double-wall view is _________? - ANSWERS NPS 3 or 3.5" OD.
Wire IQI's are placed on the weld with the wires ____________ to the weld? -
ANSWERS Perpendicular
Hole Type IQI's are normally placed ___________ to the weld. - ANSWERS Adjacent
If a hole-type IQI is used; the ________ hole must be seen in the RT. - ANSWERS 2T
hole
The preferred location for the IQI is on the ________ side? - ANSWERS Source Side
If an IQI is placed on the film side, a lead letter __________ should be placed near the
IQI. - ANSWERS F
If a shim is used under a hole-type IQI, then ________ side of the IQI should be
distinctly visible in the RT? - ANSWERS 3 side
When using a gamma radiation source, the film density limits are_________ for the IQI
and weld? - ANSWERS 2.0 to 4.0
Densitometers should be calibrated how often? - ANSWERS 90 days
What is an indication of unacceptable backscatter when taking an RT? - ANSWERS
Faint light B
Iridium 192 is used on wall thicknesses of ____________? - ANSWERS O.25" to 3.0"
Cobalt 60 is used on wall thicknesses of ______________? - ANSWERS 1.5" to 7"
When qualifying a welder with RT, what 3 indications are always unacceptable? -
ANSWERS Cracks, Lack of Fusion and Lack of Penatration
When can RT not be used to qualify a welder? What Process? - ANSWERS GMAW -
SC
How much RT is required to qualify a welder on a coupon? 1st Production weld? -
ANSWERS 6", 6"
How much RT is required to qualify a welding operator on a coupon? 1st production
Weld? - ANSWERS 6", 36"
