Open Book API 510 Practice Exam A – Questions And
Answers
A vessel is to undergo a hydrostatic test after a repair. The vessel's stress
allowable at the test temperature is 15,000 psi and its stress allowable at its
operating temperature is 13,800 psi. The vessel's MAWP at its design
temperature is 125 psi. What will be the required test pressure at the top of
the vessel? Right Ans - 176.6 psi
A cylindrical shell contains a welded long joint that is made using a backing
strip that remains in place. All of the radiography requirements of UW 12 (a)
have been met. For purposes of calculating circumferential stress on the
cylinder, what will be the value of the joint E used in the calculation? Right
Ans - .90
A small exchanger has experienced internal corrosion of its tubes. The tubes
are required to withstand an external pressure of 350 psi. The tubes have and
O. D. of 2.0 inch and are 60 inches in length with a wall thickness of .025 inch.
What would be the approximate Factor A value for this combination of length
diameter and thickness of tube is? Right Ans - .00055
An additional 4 inch nozzle was added to a pressure vessel and is similar to
the one in Fig UW-l6.1(i). The minimum thickness of the nozzle is .377 inch
and the shell minimum thickness is .750 inch. What is the decimal value of the
minimum throat required for each of two equal leg size fillet welds on this
attachment? Right Ans - .250'
A cylindrical shell has a seamless hemispherical head on one end and a
seamless ellipsoidal head on the other end. The elliptical head is attached by a
type 2 weld meeting the spot radiography requirements of UW-11(a)(5)(b).
The shell has a single longitudinal joint. All category A butt welds are type 1
with full radiography applied. The vessel will require an MAWP of 50 psi . The
material of the shell and head is SA-515-Gr. 60. The allowable stress at the
operating temperature is 15,000 psi. The heads inside diameter is 10'-0".
What is the required thickness of the 2 to 1 ellipsoidal head? Right Ans
- .200
, You have received the following tension test results for a welding procedure,
what is the ultimate unit stress for these two specimens?
Specimen | Width | Thickness
1 | .750 | .410
2 | .748 | .409
Area | Ultimate Total Load lb | Ultimate Unit Stress
.308 | 22,600 | ?
.306 | 25,800 | ? Right Ans - 1 = 73,377 2 = 84,314
An engineer is evaluating a pressure vessel's head for impact testing
requirements based on an MDMT to be marked on the vessel of 40°F. As part
of the calculations required it has been determined that this head will have a
coincident ratio of 0.60, this will allow a further reduction of the MDMT
exemption given by figure UCS-66 of___°F. Right Ans - 40
(WPS) In the JOINTS (QW-402) section, the following statement is true;
Right Ans - The box is properly addressed and contains no mistakes.
(WPS) In the BASE METAL (QW-403) there is a mistake because the; Right
Ans - There is no mistake; none of the above is true, 1 & 3 are for information
only, number 2 is not needed for this procedure because no impact tests are
required of the weldment.
(WPS) In the TECHNIQUE (QW-410) should have addressed the following;
Right Ans - Method of back gouging.
Which types of butt-welded joints are allowed to be used to construct vessels
in lethal service? Right Ans - 1 and 2 dependent upon Category.
After rolling a plate into a cylinder designed for internal pressure it is
measured for out of roundness; Right Ans - It is acceptable if it is no more
than 1% out of roundness.
During the internal inspection of a vertical vessel a minimum thickness
reading of 1.270" was found on a shell course. The Data Report reflects an
original thickness of 1.50", and allowable stress at 600 degrees of 14,500 psi,
full RT, and a MAWP of 650 psi. The MAWP was based on retirement diameter
Answers
A vessel is to undergo a hydrostatic test after a repair. The vessel's stress
allowable at the test temperature is 15,000 psi and its stress allowable at its
operating temperature is 13,800 psi. The vessel's MAWP at its design
temperature is 125 psi. What will be the required test pressure at the top of
the vessel? Right Ans - 176.6 psi
A cylindrical shell contains a welded long joint that is made using a backing
strip that remains in place. All of the radiography requirements of UW 12 (a)
have been met. For purposes of calculating circumferential stress on the
cylinder, what will be the value of the joint E used in the calculation? Right
Ans - .90
A small exchanger has experienced internal corrosion of its tubes. The tubes
are required to withstand an external pressure of 350 psi. The tubes have and
O. D. of 2.0 inch and are 60 inches in length with a wall thickness of .025 inch.
What would be the approximate Factor A value for this combination of length
diameter and thickness of tube is? Right Ans - .00055
An additional 4 inch nozzle was added to a pressure vessel and is similar to
the one in Fig UW-l6.1(i). The minimum thickness of the nozzle is .377 inch
and the shell minimum thickness is .750 inch. What is the decimal value of the
minimum throat required for each of two equal leg size fillet welds on this
attachment? Right Ans - .250'
A cylindrical shell has a seamless hemispherical head on one end and a
seamless ellipsoidal head on the other end. The elliptical head is attached by a
type 2 weld meeting the spot radiography requirements of UW-11(a)(5)(b).
The shell has a single longitudinal joint. All category A butt welds are type 1
with full radiography applied. The vessel will require an MAWP of 50 psi . The
material of the shell and head is SA-515-Gr. 60. The allowable stress at the
operating temperature is 15,000 psi. The heads inside diameter is 10'-0".
What is the required thickness of the 2 to 1 ellipsoidal head? Right Ans
- .200
, You have received the following tension test results for a welding procedure,
what is the ultimate unit stress for these two specimens?
Specimen | Width | Thickness
1 | .750 | .410
2 | .748 | .409
Area | Ultimate Total Load lb | Ultimate Unit Stress
.308 | 22,600 | ?
.306 | 25,800 | ? Right Ans - 1 = 73,377 2 = 84,314
An engineer is evaluating a pressure vessel's head for impact testing
requirements based on an MDMT to be marked on the vessel of 40°F. As part
of the calculations required it has been determined that this head will have a
coincident ratio of 0.60, this will allow a further reduction of the MDMT
exemption given by figure UCS-66 of___°F. Right Ans - 40
(WPS) In the JOINTS (QW-402) section, the following statement is true;
Right Ans - The box is properly addressed and contains no mistakes.
(WPS) In the BASE METAL (QW-403) there is a mistake because the; Right
Ans - There is no mistake; none of the above is true, 1 & 3 are for information
only, number 2 is not needed for this procedure because no impact tests are
required of the weldment.
(WPS) In the TECHNIQUE (QW-410) should have addressed the following;
Right Ans - Method of back gouging.
Which types of butt-welded joints are allowed to be used to construct vessels
in lethal service? Right Ans - 1 and 2 dependent upon Category.
After rolling a plate into a cylinder designed for internal pressure it is
measured for out of roundness; Right Ans - It is acceptable if it is no more
than 1% out of roundness.
During the internal inspection of a vertical vessel a minimum thickness
reading of 1.270" was found on a shell course. The Data Report reflects an
original thickness of 1.50", and allowable stress at 600 degrees of 14,500 psi,
full RT, and a MAWP of 650 psi. The MAWP was based on retirement diameter
