This article is about interview preparation question and answers of piping and mechanical engineers related to API 574 international code and standard.
API 574 is a recommended practice published by the American Petroleum Institute (API) titled “Inspection Practices for Piping System Components.” It provides guidelines for inspection, repair, alteration, and rerating activities for in-service piping systems and their components in the petroleum, petrochemical, and chemical process industries.
Question and Answers for Piping & Mechanical Engineers.
1. The recommended practice API 574 covers the inspection of;
A. piping only
B. tubing piping
C. control valves
D. Piping, tubing, valves and fittings.
2. A loss of ductility and notch toughness in susceptible law-alloy steels, such as 1-1/4 Cr and 2-1/4 Cr, due to prolonged exposure to high-temperature service [700°F – 1070° F (370°C – 575 ° C)]. Is defined as_______ ?
A. Creep
B. Intergranular corrosion
C. 885 °F embrittlement
D. temper embrittlement.
3 . The refining industry most commonly uses ____ seamless piping.
A. A-317
B. A-106
C. A-53
D. A-516 Gr.70.
4. Steel and alloy piping are manufactured to standard dimensions in nominal” pipe sizes up to;
A. 24 inches.
B. 48 inches.
C. 52 inches.
D. 36 inches.
5. Above what diameter is piping also constructed by the rolling and welding of plate?
A. 12″
B. 16″
C. 24″
D. 36″
6. The traditional thickness designations-standard weight, extra strong, and double extra strong-differ from schedules for nominal pipe sizes up to;
A. 24 inches.
B. 48 inches.
C. 36 inches.
D. 12 inches.
7. The actual thickness of wrought piping may vary from its nominal thickness by a manufacturing under tolerance of as much as;
A. + or – 12.5%
B. 12.5%
C. 12.5% or 0.01″ whichever is greater.
D. 10%
8. What method (s) are not used to fabricate valve bodies used in piping systems?
A. Casting and forging
B. Machined from bar stock
C. Building up by welding
D. Inverse casting using the Robertson method of lost wax.
9. Reduced port valves are one type of;
A. globe valve
B. plug valve
C. Control valve
D. gate valve
10. Which of the following describes a globe valve?
A. Consists of a tapered or cylindrical plug fitted snugly into a correspondingly shaped seat in the valve body.
B. This type of valve is normally used in a fully open or fully closed position.
C. Consists of a valve body that contains a disk which moves axially to the disk centerline against a seat.
D. They are well suited for conditions that require quick on off or bubble tight service.
11. A. ____ valve consists of a tapered or cylindrical plug fitted snugly into a correspondingly shaped seat in the valve body.
A. Ball
B. Taper
C. Plug
D. Merrick Plug.
12. A pack less valve that contains an element made of a flexible material is called;
A. A check valve
B. A diaphragm valve
C. A ball valve
D. A jameson diaphragm valve
13. A butterfly valve is described as;
A. a valve that is used to automatically prevent backflow
B. It basically consists of a flat plate that slides against a seat.
C. a valve in which a one quarter turn of the stem changes the valve from closed to completely open.
D. a specialized gate valve generally used in erosive or high-temperature.
14. Which of the following describes a check valve ‘s principle of operation?
A. Hydraulic up-lift
B. Ball retained captive
C. Spring-loaded vanilla wafer
D. Swing or lift-piston.
15. ASME BI 6.5 covers flanges of various materials through a nominal pipe size of 24 inch which of the following covers larger flanges?
A. API standard 605 and MSS SP-44
B. API standard 605
C. MSS SP-44
D. ASME B16.47.
16. Threaded joints are generally limited to piping in non-critical service that has a nominal size of;
A. 2 inches or smaller.
B. 3 inches or smaller.
C. 24 inches or smaller.
D. I inches or smaller.
17. Name a cautionary technique required during assembly of socket-welded pipe fittings?
A. Space must be provided between the end of the pipe and the bottom of the socket to allow for pipe expansion and weld shrinkage.
B. A bevel at the end of the pipe to allow for pipe expansion and weld shrinkage.
C. Expansion and weld shrinkage should be measured and recorded.
D. Space must be provided between the end of the pipe and the root opening of any butt joints.
18. ____ Welded joints are made by inserting the end of the pipe into a recess in a fitting or valve and then fillet welding the joint?
A. Friction
B. Butt
C. Electric Resistance
D. Socket
19. A large number of piping failures occur at;
A. small radii elbows
B. Large radii elbow
C. flanges
D. pipe-to-pipe welded branch joints.
20. ____ Pipe joints can be of the flanged, packed, sleeve, hub-and-spigot-end or hub-and-plain-end or bell-and-spigot-end or bell-and -plain-end type.
A. Cast Iron
B. Proprietary
C. Socket
D. Forged
21. Tubing cannot be joined by;
A. Welding
B. soldering
C. brazing
D. Smithson bonding system in critical service.
22. The advantage (s) of special joints described as proprietary is (are)?
A. They can tolerate significant axial or lateral movement
B. They are normally fit for use at higher pressures and temperatures
C. The bolting arrangements are not unique and easily assembled
D. They are usually less expensive than standard fittings
23. Of the following which is not considered to be the primary purpose of piping inspections?
A. quality assurance
B. plant safety
C. reliability
D. employment of inspection personnel
24. Possibly leaks at flanged joints are may occur;
A. during startup and sometimes after reaching operational temperature
B. during shutdowns and sometimes after reaching operational temperature
C. during startup or shutdowns and sometimes after reaching operational temperature
D. When proper bolting is used with a proven bolting procedure.
25. Before any method of inspection is adopted for piping what should be checked?
A. NBIC
B. ASME B31 .3
C. API 570
D. Regulatory requirements
26. Regulatory requirements normally cover which of the following concerns with piping;
A. maximum diameters limits of piping for a given lethal service.
B. the length between inspections of piping systems
C. safety
D. Safety and reliability
27 . An example of where creep cracking has been experienced in the industry is in;
A. 2- l/4 Cr steels above 800 °F
B. l – l/4 Cr steels above 900 °F
C. 2-1/4 Cr steels above 900 °F
D. Chrome Vanadium steels above I 000 °F
28 . Which of the following describes where erosion can normally found in piping systems?
A. Upstream of valves
B. Upstream and downstream of valves
C. Downstream of valves
D. At the first change of direction upstream of valves
29 . Thicker material sections have a lower resistance to brittle fracture due to higher constraint which increases coaxial stresses at the crack tip. What document has more information on brittle fracture of metals?
A. API 510
B. API 6531
C. API RP 571
D. API RP 57 7
30 . Which of the following is not an example of environmental cracking?
A. Chloride SCC of austenitic stainless steels
B. polyphonic acid SCC of sensitized austenitic alloy steels
C. Carbonate SCC
D. Low Temperature SCC
31. What should all linings piping surface; it is particularly important to determine whether such deposits have;
A. separations
B. breaks
C. holes and blisters
D. separations, breaks, holes and blisters
32. Where operating deposits, such as coke, are present on a pipe surface, it is particularly important to determine whether such deposits have;
A. eroded the refractory lining
B. active corrosion beneath them
C. bonded to the pipe
D. the opportunity to dislodge and flow downstream in a circuit fouling machinery and instrumentation.
33. If excessive temperatures are encountered in piping;
A. the piping system must be discontinued from service
B. a sufficient nwnber of measurements shall be taken to determine accurately the remaining thickness of the piping.
C. mechanical properties and micro-structural changes may take place.
D. mechanical properties and micro-structural changes may take place.
34. What type of cracking in a piping system can occur at normal operating at design conditions?
A. Creep
B. Linear
C. Stress corrosion
D. Thermal expansion cracks.
3 5. Which method of inspection will not find creep cracking?
A. PT.
A. b. UT.
B. ET
C. VT.
36. Brittle fracture in piping is usually not a concern for;
A. Thick walled piping at ambient temperatures
B. Thick walled piping at elevated temperatures
C. Relatively thin wall piping
D. Relatively thjck wall piping
37. As concerns brittle fracture of a piping material during testing, special attention should be given to lowalloy steels ( especially 2 ¼ Cr- l Mo material), because they may be prone to;
A. intergranular corrosion
B. stress corrosion cracking
C. temper embrittlement
D. 885°F embrittlement
38. Erosion in piping is not characterizes by;
A. grooves
B. rounded holes
C. waves and valleys
D. general corrosion over a large area.
39. An effective corrosion inspection program includes which of the following elements;
A. An inspector with knowledge of the service and where corrosion is likely to occur
B. Non-occasional use of nondestructive examination (NDE)
C. Non-extensive use of nondestructive examination (NDE)
D. An operator with knowledge of the service and where corrosion is likely to occur.
40. When determining the frequency of inspection for piping in general which of the following must be considered?
A. The year of service
B. The operating temperature if it is below freezing
C. The lack of inspection tools
D. The degree of risk, and remaining corrosion allowance
41. The frequency and thoroughness of piping inspections will range from often and complete where deterioration is extreme, to seldom and cursory in no-corrosive services, which of the following would not cause a more frequent inspection cycle.
A. The amount of corrosion allowance remaining
B. The historical data available
C. Regulatory requirements
D. A survey by the EPA.
42. The frequency of piping inspections should not be determined by which of the following conditions?
A. The amount of corrosion allowance remaining
B. The degree of risk
C. The severity of service
D. Operational schedules
43. Which of the following is not a benefit of performing on-stream inspections?
A. Extending process runs and preventing some unscheduled shutdowns
B. Permitting fabrication of replacement piping before a shutdown
C. Eliminating work and reducing personnel requirements for a shutdown
D. Pipe corrosion rate is reduced.
44. On stream inspection will not reduce downtime by the following means;
A. leaks in piping systems can be most easily detected while the equipment is operating.
B. Pipe supports can be inspected for distortion and damage
C. Pipe anchors may be inspected to determine their condition
D. temperature reading taken with infra-red equipment
45. If piping is found to be swaying what should be examined?
A. Welds should be checked for cracks particularly at points of restraint.
B. Points of restraint
C. Weld should be checked for cracks in socket welds
D. All insulation and coatings for damage
46. What areas are not required to be inspected when vibration is observed in piping during visual
inspections?
A. At the small connections which have a heavy valve attached
B. At small lines that are tied down to larger lines
C. Areas where piping is attached to equipment and in the vicinity of anchors
D. Long straight well supported runs of small bore piping.
47. Defects in protective coatings and the waterproof coating of insulation should be removed from;
A. Vertical piping runs
B. small diameter vertical runs
C. small connections, such as bleed lines and gauge connections
D. Insulation around major valves and fittings.
48. What is a clear indication of a possible hot spot in a piping system?
A. Constants lifting of over pressure protection
B. Erratic gage readings upstream
C. A decrease in downstream pressure accompanied by a decrease in flow.
D. A red glow found after dark.
49. Which of the following is not an advantage of radiography over other inspection methods?
A. Pipe insulation can remain intact
B. The metal temperature of the line has little bearing on the quality of the radiograph
C. The position of internal parts of valves (dropped gates) can be observed.
D. Radiography can find cracks in all orientations much better than other techniques
50. Concerning radiography of the following which is not an advantage?
A. Pipe insulation can remain intact
B. The metal temperature of the line has little bearing on the quality of the radiograph
C. Radiography equipment is easily maneuverable in the refinery
D. It is excellent at finding flaws in plastic piping welds
51 . When sever fouling is found in a piping system, what should be done prior to cleaning the lines?
A. Samples should be taken and analyzed
B. A section of piping should be removed and split to determine if there is corrosion underneath the fouling deposits
C. extensive thickness reading should be taken.
D. Consult with the chief inspector or Engineer.
52. Flanged joints that have been opened should be visually inspected for;
A. Overheating
B. Any enlargement of bolting holes
C. Caustic attack
D. Corrosion and defects such as scratches. Cuts. And gouges in gasket seating faces
53. What type of liquid penetrant should be used on austenitic materials?
A. Visible dye.
B. Fluorescent dye
C. Penetrant that are low in sulfides
D. Penetrants that are low in or contain no chlorides.
54. Gate valves should be measured for thickness between the;
A. inlet and outlet connections
B. the seats
C. the stem area and the bonnet
D. the bonnet and packing gland area
55. What is the recommended minimum to be done during inspection of valves in severe service?
A. Valves should tagged per B31.3
B. Valves should be dismantled to inspect internal parts
C. All valves should be thickness measured between their seats
D. Valves shall be inspected with remote visual camera as a minimum.
56. When a valve body and/or closure pressure tests are performed after servicing, they should be conducted in accordance with;
A. API standard 498
B. B American valve institute standard 51 3.
C. API standard 598
D. OSHA regulations
57. When inspecting quarter turn valves, what should they always be inspected for?
A. Micro fissures in the valve body
B. Valve should be inspected for ease of operation and the ability to open
C. All seating surfaces should be inspected for large tools left behind.
D. All seating surfaces should be inspected and they should be checked for the ability to open and close completely.
58. Which of the following does not describe a common type of flange used in piping?
A. Welding neck
B. Slip-on
C. Lap joint
D. threaded socket
59. Of the following items which is a not a possible cause of a clamped joint leak?
A. Because of dirt or corrosion
B. Because of mechanical damage
C. Because of failure of the clamp to provide sufficient force
D. Because of failure of the clamp to provide excessive force
60. If misalignment of piping was noted during operation. The cause should be determined and corrected. Misalignment is usually caused by the following condition(s);
A. Adequate provision for expansion
B. Delaminated anchors or guides
C. Properly adjusted hangers of the wrong diameter
D. Inadequate provision for expansion, broken hangers, and defective anchors.
61. One advantage of steam pressure testing piping after a welded repair is;
A. that it heats the piping, thereby stressing weld in piping that could have passed a water test.
B. that it heats the piping, thereby popping flux from welds in piping that could have passed a water test.
C. that it hearts the piping thereby preventing any possibility of brittle fracture during the test.
D. steam is easily obtained and does not leave permanent residues.
62. The hammer test is _________ _
A. used on all piping
B. used on stress relieved lines in caustic and corrosive service
C. an outdated method of inspection
D. used primarily on high alloy piping with chrome content of about 2-1/4%
63. Underground piping is usually given Above-Grade Visual Surveillance by;
A. a series of measurements of the electrical resistance of the surrounding soil
B. excavating and uncovering the piping for several feet at practical intervals
C. isolating and draining and using internal radiographic techniques
D. an inspection at and just below the point where it enters the earth, asphalt, or concrete.
64. What indications of leakage should be inspected for above ground, when examining buried piping?
A. Moist ground or seepage above the buried piping
B. Sunken ground above the buried piping
C. Cracking of the ground above the buried piping
D. Black deposits indicating a change in the soil makeup
65. In general how is the extent of inspection for new piping construction determined?
A. All piping weld shall be l 00% inspected
B. The extent of inspection during fabrication and installation depends largely on the severity of the service and the quality of the workmanship
C. All piping welds shall be randomly inspected
D. All piping is inspected based on the type of weld made during the fabrication in field.
66. How does API 574 address the inspection of materials used in piping systems?
A. All materials must conform to ASME section 2 part A or B
B. Both materials and fabrication should be checked for conformance with the codes and specifications that are appropriate for the plant
C. All Materials must be listed in ASME B3 I .3
D. All Materials shall be the highest commercial quality easily obtainable.
67. Deviations from specifications or standards for material tolerances, or workmanship are usually evaluated on the basis of;
A. Their effects on such factors as safety. strength ,corrosion resistance, and serviceability.
B. Jurisdictional requirements.
C. Economic impact.
D. Ease of construction.
68. ASME 831 .3 requires that the following be taken into account when pipe thickness is determined;
A. Consultation with the jurisdiction.
B. Time required to repair, and personnel safety.
C. Suitability for a given fluid service.
D. Corrosion allowance.
69. Which of the following is the simplest of the formulas used for the determination of thickness required for in service piping?
A. Lame’ equation.
B. Barlow formula.
C. tm = t+c.
D. Hoop stress formula.
70. When establishing the minimum thickness of a valve body, the proper calculation would be;
A. 1.5 times (1.25 times for class 2500) the thickness of a simple cylinder designed for a stress of 6000 pounds per square inch.
B. 1.5 times (1 .35 times for class 4500) the thickness of a simple cylinder designed for a stress of 7000 pounds per square inch
C. 1.5 times (1.35 times for class 4500) the truckness of a simple cylinder designed for a stress of 8000 pounds per square inch.
D. 1.5 times (1.25 times for class 4500) the thickness of a simple cylinder designed for a stress of 6000 pounds per square inch.
71. The thickness of valves and flanged fittings is substantially greater that of a simple cylinder because;
A. Of required fabrication method.
B. They are made of cast materials which are inherently weaker than piping materials.
C. Valves are subject to closing stress ·concentrations because of their shape.
D. They are made of forged materials.
72. As regards the calculation of the thickness required for a valve made of an unknown material;
A. It shall be calculated to be I .5 times a simple cylinder of the same diameter as the valve opening using a stress value of 12,500 psi.
B. it shall be calculated to be 1.5 times a simple cylinder of the same diameter as the valve opening using a stress value of 7,000 psi .
C. it shall be calculated to be 1.5 times a simple cylinder of the same diameter as the valve opening using a stress value of I 0,500 psi .
D. it is impossible to calculate without the original design information.
73. What should all piping inspection records not necessary contain?
A. specification and strength levels of materials used.
B. original thickness measurements.
C. original data of installation.
D. The name of all welders who fabricated the piping.
74. What important aspects of a piping system can sketches not address?
A. The assist at future inspections in determining location that urgently require examination.
B .They identify points to be opened for visual inspection and parts that require replacement or repair.
C .They identify piping systems in terms of location size and material speciation .Also general process flow, and service conditions.
D. The competency of inspects
75. Prior to a scheduled piping inspection previous inspection records should be reviewed. The reason for the review is so;
A you can assign to the work to contactors.
B. A list can be made of all predictable repairs and replacement.
C. Areas that are not approaching retirement thickness can be determined.
D. A Schedule can be made to determine the inspection force requirements to locate areas reaching retirement thickness, and predict repairs or repairs or replacements.
76. For the purpose of planning repairs and other needs how can inspection record be used?
A Determine the type of NDE required
B. A list can be made of all predictable repairs and replacements
C. In assisting process personnel in determining the number of personnel required during the shutdown period.
D. To determine the names of all welders who performed a repair in the past.
77. Historical records of piping should be studied to determine;
A when the last inspection was made and who performed it.
B. determine which sections will be approaching retirement thickness at the next planned shutdown.
C. who performed the last inspection.
D. determine if any welded repairs are present.
API 574 Question Answers {Answer Key}
SL. ANSWER REFERENCE
1. D
2. D
3. B
4. B
5. B
6. B
7. B
8. D
9. D
10.C
11.C
12.B
13. C
14.D
15. D
16.A
17. A
18. D
19.D
20.A
21.D
22.A
23.D
24.C
25. D
26. C
27. B
28.D
29.C
30.D
31.D
32.B
33.C
34.A
35.D
36.C
37. C
38. 0
39.A
40. D
41. D
42.D
43.D
44. D
45.A
46.D
47.C
48.D
49. D
50.D
51.A
52.D
53.D
54.B
55. B
56.C
57.D
58.D
59.D
60.D
61. A
62.C
63.D
64.A
65.B
66.B
67.A
68. D
69. B
70. B
71.C
72.B
73.D
74.D
75.D
76. B
77.B