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API 510 Sample Questions | Free Practice Test

API 510 exam questions

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Question 1 of 80

1. Which of the following types of discontinuities is NOT normally detected by radiography?

Question 1 of 80

Question 2 of 80

2. API 510 __________ be used as a substitute for the original construction of pressure vessels before it is placed in-service.

Question 2 of 80

Question 3 of 80

3. A pressure vessel has an actual average thickness of 12.5mm (1/2") and a corrosion allowance of 2.5 mm. The vessel is placed in a corrosion free environment and not thickness reduction was observed. What thickness is used when calculating MAWP?

Question 3 of 80

Question 4 of 80

4. Who establishes inspection interval for thickness measurements and external visual inspections.

Question 4 of 80

Question 5 of 80

5. ASME Sec. VIII Div. 1 is based on factor of safety equal to

Question 5 of 80

Question 6 of 80

6. Identify incorrect statement from following, if any.

Question 6 of 80

Question 7 of 80

7. In plate specification A 516 Gr 70, the letter A indicates:

Question 7 of 80

Question 8 of 80

8. The symbol which indicates ASME code stamping for vessels manufactured to ASME Section VIII Div. 1 is

Question 8 of 80

Question 9 of 80

9. What will be the applicable mandatory Edition and addenda for ASME Sec. VIII, Div. 1 to be used if contract for manufacturing a new vessel was signed on 14 December 2011?

Question 9 of 80

Question 10 of 80

10. Term "E" used in shell thickness formula  in ASME Sec. VIII Div.1, represents weld joint efficiency, whose value is equal to "1", if:

Question 10 of 80

Question 11 of 80

11. A restoration work by weld-overlay was carried out on corroded wall of vessel and it can now be used as per the design conditions of the vessel. This activity will be termed as:

Question 11 of 80

Question 12 of 80

12. In certain MT Check of pressure Vessel, The size of "indication" for a certain discontinuity was seen as 4 mm but after the MP Check and using magnifying glass it was seen having actual size as 2.5mm only. If stipulated acceptance criterion for that type of discontinuity was 3 mm, your decision is:

Question 12 of 80

Question 13 of 80

13. ASME Code requires averaging of impact test values of how many specimens for the relevant acceptance criteria.

Question 13 of 80

Question 14 of 80

14. A stainless steel weld has a crack open to the surface. Which NDT method will reveal it most effectively?

Question 14 of 80

Question 15 of 80

15. PQR document normally may be revised and re submitted for acceptance.

Question 15 of 80

Question 16 of 80

16. Hot tapping is best described by statement:

Question 16 of 80

Question 17 of 80

17. Which of the following represent grouping of weldment in ASME IX?

Question 17 of 80

Question 18 of 80

18. An inspector should be stricter while carrying out inspection on:

Question 18 of 80

Question 19 of 80

19. PT examination is used to detect the surface cracks in welds as well as in base metal plates. For proper detection,

Question 19 of 80

Question 20 of 80

20. As per ASME Sec. VIII Div. 1, “Weld joint category” means:

Question 20 of 80

Question 21 of 80

21. When reviewing a group of radiographs all of the following information shall be documented except.

Question 21 of 80

Question 22 of 80

22. During a repair of a pressure component a section is to be replaced due to corrosion.

A rectangular butt weld insert plate measuring 18 in width by 24 in length by 2 in thick will be used in the repair.

According to ASME PCC-2,what is the minimum corner radius of the insert plate allowed?

Question 22 of 80

Question 23 of 80

23. For hot tapping and in service welding repairs an extra low hydrogen filler material should be used for welding carbon steel materials with a carbon equivalent greater than 0.42% to limit the potential for

Question 23 of 80

Question 24 of 80

24. weld overlay is used to repair an area of localized metal loss.

The original metal thickness is 0.75 in. (19.05 mm) including 0.125 in (3.18 mm) corrosion allowance.

The depth of metal lost by corrosion and weld preparation is 0.25 in (6.35 mm).

The filler metal tensile strength is 60 ksi (413.7 MPa), while the base metal sile strength is 70 ksi (482.6 MPa).

What is the thickness of repair weld metal required?

Question 24 of 80

Question 25 of 80

25. Calibration and verification of positive material identification testing equipment to determine the equipment performance should be done

Question 25 of 80

Question 26 of 80

26. Which of the following is an API 510code requirement when performing control deposition welding during a vessel repair?

Question 26 of 80

Question 27 of 80

27. In magnetic particle examination the direction of magnetization shall be determined by particle indications obtained using an indicator or shims the magnetizing technique
shall be changed when aclearly defined line of particles is not performed in

Question 27 of 80

Question 28 of 80

28. A 96 in.- (2.438 mm) diameter vessel has been in operation for 10 years.

The original thickness of the top head was 0438 in. (11.15 mm.)

The current thickness of the top head is 0.293 in. (7.44 mm).

The minimum allowable working pressure of the vessel is being lowered to 80 psig (0.55 MPa) in a rerate.

The minimum thickness of the head based on the new maximum allowable working pressure is 0.250 in. (16.35mm).

What is the maximum interval for internal inspection of the head?

Question 28 of 80

Question 29 of 80

29. The type of corrosion caused by sulfidation is most often associated is

Question 29 of 80

Question 30 of 80

30. Which of the following materials is most susceptible to high-temperature hydrogen attack (HTHA)?

Question 30 of 80

Question 31 of 80

31. An “A” number on a welding procedure corresponds to which of the following.

Question 31 of 80

Question 32 of 80

32. During the inspection of a horizaontal pressure vessel an ellipsoidal head has the following Dimensions:
Thickness = 1.25 in.
Inside diameter of the skirt = 48 in
Inside radius of the dish = 48 in
S=15000 PSI
E=1

What is the MAWP for this head without corrosion allowance?

Question 32 of 80

Question 33 of 80

33. In a sour crude refinery, a carbon steel tray is removed from a fractionation lower section that operate above 500 F (260 C).

The tray is thin throughout, and its type 410 stainless steel tray valves relatively uncorroded.

Which of the following is most likely to responsible to the damage?

Question 33 of 80

Question 34 of 80

34. In process equipment, caustic injection points are designed to allow proper mixing and dilution of caustic to avoid:

Question 34 of 80

Question 35 of 80

35. A carbon-steel pressure vessel is to be put into a caustic service (solution of 30% by weight) at a temperature of 140 °F (60°C) and a pressure of 176 psig (1.21 MPa). Considering caustic stress corrosion cracking (caustic embrittlement), which of the following is the most appropriate statement?

Question 35 of 80

Question 36 of 80

36. A Stainless steelweld overlay is repaired on a vessel fabricated from P-5 material.

The next day the base metal in the repair area should be examined for cracking by which type of examination.

Question 36 of 80

Question 37 of 80

37. Calibration of magnetizing equipment for magnetic particle examination shall occur

Question 37 of 80

Question 38 of 80

38. A vessel made of P-3 Group 1 material with notch toughness testing not required was found to have a crack and the excavation depth after removal was measured to be 0.875 in deep.

Which of the following can be used in lieu of postweld heat treated?

Question 38 of 80

Question 39 of 80

39. In accordance with ASME BPVC SECTION V RETENTION Of examination records and related documents shall be specified by the

Question 39 of 80

Question 40 of 80

40. Before internal inspection of a pressure vessel starts, it is recommended that

Question 40 of 80

Question 41 of 80

41. A hot spot that has been dentified on a carbon steel vessel that had operated above 750 Psi extended amount of time.

Which of the following actions should not be taken?

Question 41 of 80

Question 42 of 80

42. Gamma-ray radiography is used to perform inspection on a repair weld of a vessel that is 1.250 inches (31.8 mm) thick.

The radiographer has access to both sides of the weld.

The hole-type IQI (Penetrameter) is:

Question 42 of 80

Question 43 of 80

43. Which of the following essential variables addressed by WPS in GTAW welding process? Choose incorrect answer.

Question 43 of 80

Question 44 of 80

44. Which of the following criteria must be met in order to use thickness averaging? Choose incorrect answer.

Question 44 of 80

Question 45 of 80

45. A radiographer contractor is using iridium-192 as the source for radiation energy.

What is the lower threshold of the thickness range for which this method is normally used.

Question 45 of 80

Question 46 of 80

46. Which of the following methods results in a highly discrete stream of drops that accelerates by ARC forces?

Question 46 of 80

Question 47 of 80

47. Supplemental Essential variables must be addressed on the WPS when:

Question 47 of 80

Question 48 of 80

48. Although fatigue cracking is generally considered to be a design related mechanism, once a crack is initiated, the rate of crack growth:

Question 48 of 80

Question 49 of 80

49. Which of the following welds are usually highly resistant to chloride stress corrosion cracking?

Question 49 of 80

Question 50 of 80

50. CUI is a concern for duplex stainless steel operating in the temperature range of 280°F (140°C) to 350°F (175°C) when what damage mechanism is a concern?

Question 50 of 80

Question 51 of 80

51. For valves in acidic or caustic service, after pre-pop testing, the pressure relief valves should be:

Question 51 of 80

Question 52 of 80

52. A signal of discontinuity in the material under nondestructive examination is considered:

Question 52 of 80

Question 53 of 80

53. Under what circumstances, CMLs may be reduced or eliminated?

Question 53 of 80

Question 54 of 80

54. Any welding repair should be performed according to the procedure accepted by the:

Question 54 of 80

Question 55 of 80

55. What is the first thing that should an inspector do after a rejectable defect identified?

Question 55 of 80

Question 56 of 80

56. which type of ultrasonic display shows the amplitude of the signal coming from a discontinuity coming as a function of time?

Question 56 of 80

Question 57 of 80

57. process parameters exceedances can be held in check by:

Question 57 of 80

Question 58 of 80

58. Under what circumstances, CMLs may be reduced or eliminated?

Question 58 of 80

Question 59 of 80

59. Pressure-relief valves in fouling service that have lifted while in service:

Question 59 of 80

Question 60 of 80

60. Corrosion and other damage identified during inspections and examinations must be characterized, sized, and evaluated per Section 7 (Inspection Data Evaluation, Analysis, and Recording) with deviations from the inspection plan being approved by whom?

Question 60 of 80

Question 61 of 80

61. When using PT for weld inspection, the length of time the penetrant remains on the surface is known as:

Question 61 of 80

Question 62 of 80

62. Question: The welding performance qualification is only limited by:

Question 62 of 80

Question 63 of 80

63. Which of the following is the acceptable method to address in-process PMI during the welding?

Question 63 of 80

Question 64 of 80

64. Which of the following increases the likelihood and severity of amine stress corrosion cracking?

Question 64 of 80

Question 65 of 80

65. Question: When calibrated for metal analysis, which device can provide qualitative and quantitative information to determine which elements are present and in what quantity?

Question 65 of 80

Question 66 of 80

66. Pressure test pressure, duration and procedures used should be in accordance with the applicable construction code requirements and applicable procedures of the:

Question 66 of 80

Question 67 of 80

67. Reverse acting scored rupture disks provide satisfactory service life when operating pressure at what percent of the marked burst pressure?

Question 67 of 80

Question 68 of 80

68. Pressure test pressure, duration and procedure used should be in accordance with the applicable construction code requirements and applicable procedure of the:

Question 68 of 80

Question 69 of 80

69. What material is generally resistant to caustic corrosion until the passivity is damaged?

Question 69 of 80

Question 70 of 80

70. Low-alloy steel piping and equipment susceptible to atmospheric corrosion when operating: OA. below 250°F (120°C).

Question 70 of 80

Question 71 of 80

71. Are non-integrally bonded metallic liners counted as a part of the pressure boundary of a pressure vessel?

Question 71 of 80

Question 72 of 80

72. The next planned inspection of a pressure vessel shall include all CMLS that have which of the following corrosion rate and remaining life descriptions?

Question 72 of 80

Question 73 of 80

73. A competent person who has met the knowledge, skill requirements and expectations of the owner/user is defined as:

Question 73 of 80

Question 74 of 80

74. Where does crevice corrosion occur?

Question 74 of 80

Question 75 of 80

75. Question: When inspecting a pressure vessel with riveted seams, examination should include: OA. UT of the rivet to look for a gap between the shank and the hole.

Question 75 of 80

Question 76 of 80

76. The intent of API 510 is to:

Question 76 of 80

Question 77 of 80

77. External inspection intervals for vessels in non-continuous service are the same as continuous same service vessels because:

Question 77 of 80

Question 78 of 80

78. An assembly installed in the space between a rupture disk and another relief device to detect or prevent the accumulation of pressure between the rupture disk and the other
device is a:

Question 78 of 80

Question 79 of 80

79. An assembly installed in the space between a rupture disk and another relief device to detect or prevent the accumulation of pressure between the rupture disk and the other
device is a:

Question 79 of 80

Question 80 of 80

80. When rupture disks are removed from the rupture disk hole, they:

Question 80 of 80


 

 

 

How the exam questions developed? 

Periodically a question writing session is conducted.  Subject Matter Experts (SME’s), or individuals who specialize in pressure vessels, write questions from specific sections of the Code.  Each question is then checked by three other SME’s.

 

This validation exercise answers two questions.

  1. Is the question written clearly?
  2. Does the question cover knowledge that is important to a vessel inspector?

These questions then go into a question databank as non-scored exam question.

 

Presently there are over 1000 questions in the databank and are grouped by topics.  For each examination, there are 170 questions on the exam pulled in specified proportion from various categories. Only 140 Questions are scored. The remaining 30 are pre-test questions and not marked towards your score, meaning these pre-test questions do not affect your score whether you have answered them correctly or incorrectly. API does not tell you which ones these questions are.

API needs to ensure that these questions are not significantly challenged by the candidates and also has been answered by a reasonable number of people before adding them to their question bank as scored questions.

 

Publications Effectivity Sheet & Body of knowledge

Publications effectivity sheet is the list of applicable reference documents that you need to study for the exam. It also tells you which sections of each document are applicable. It can be revised from time to time when the codes and recommended practices or their addendum are revised and becomes applicable. Red texts indicate a revision or a change from the previous API Effectivity Sheet.

 

Body of knowledge also list the reference codes and recommended practices (without revision number) and elaborates on topics that a pressure vessel inspector needs to know giving examples. It shows what you are expected to know.

 

From time to time, API conducts a Job Analysis to re-evaluate the API 510 exam to ensure that it remains relevant and continues to focus on the inspectors’ core competencies. As a part of this process, the publication effectivity sheet and body of knowledge is revised. For example, API 510 Publications Effectivity Sheet applicable for exams held between September 2022, January 2023, and May 2023.

 

Number of Exam Questions per Code and RP

As per Effectivity Sheet for API-510 exam, there are 4 codes (API 510 code & ASME Codes V, VIII & IX) and 4 Recommended Practices (RP) prescribed for examination.

However, all of them are not equally important and therefore, do not require equal emphasis.

 

About 40% of questions are asked from API 510 code which is some 60 pages long, while the rest contribute to remaining 60% which are 2000 pages long.

 

Code Approximate Percentage of Questions
API 510 Code & API 572 50 – 51
ASME Sec. Vlll Div.1 8 – 10
ASME Sec. IX & API 577 8 – 10
ASME Sec. V 8 – 10
API RP 571 5 – 6
API RP 576 & 578 5 – 6
PCC-2 5- 6
Gen. Knowledge 3-4

 

Below table shows area of examination versus maximum number of exam questions and should give you a fair idea of how important each part of Body of Knowledge is.

 

Area of Examination                     Maximum No. of Questions

Scope and General Application of 510                            5

Damage Mechanisms                                                     15

Repairs                                                                             15

NDE                                                                                 15

(Procedures, limitations, advantages, techniques, responsibilities, applications)

Welding                                                                               15

Design                                                                                 10

Planning                                                                              20

Inspection and Testing Practices                                       15

Pressure Relief Devices                                                        4

Data Evaluation                                                                    20

Roles and Responsibilities                                                    6

Total Score                                                                            140

Add another 30 non scored questions that are distributed across the topics.

 

No Negative Marking

The pass mark is roughly 70% for all the API examinations. No negative marking is applied. Therefore, make sure that you have answered all the questions. At the end, click the ‘’review all’’ button and peruse through the list to ensure that you have not skipped any question. You can also check ‘’review incomplete questions’’ to ensure there is nothing on the list, that is, no question left unanswered.

 

 

 

 

Click below Study our free lessons and quiz:

 

 

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