I85PREP
⌘ K
NBBI Authorized Inspector (AI) study materials
NBBI Authorized Inspector (AI) study resources

NBBI Authorized Inspector (AI) practice questions

One question at a time. Build your NBBI Authorized Inspector (AI) understanding.

First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

Continue in the practice tool above to load more questions, 50 at a time.

Question 1ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A power boiler is constructed to ASME Section I and is stamped by the Manufacturer before shipment. Which symbol stamp must appear on the boiler?

  1. S Correct answer.
  2. U
  3. M
  4. H

Explanation

Section I power boilers carry the "S" symbol stamp applied under the Manufacturer's quality control program and are documented on the Section I data report. The other stamps identify equipment built to different code sections: "H" for Section IV heating boilers, "U" for Section VIII Division 1 vessels, and "M" for miniature boilers.

Question 2ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A steam heating boiler is to be built under ASME Section IV. What is the maximum allowable working pressure permitted for a steam heating boiler within the scope of that Section?

  1. 250 psig
  2. 300 psig
  3. 15 psig Correct answer.
  4. 160 psig

Explanation

Section IV covers steam heating boilers limited to 15 psig maximum allowable working pressure, and hot water heating boilers limited to 160 psig and 250 degrees F. Equipment outside those limits falls under Section I.

Question 3ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 shell course is joined by a Type 1 double-welded butt joint that receives full radiography of its full length. What joint efficiency E applies to that seam?

  1. 0.85
  2. 0.70
  3. 1.00 Correct answer.
  4. 0.90

Explanation

UW-12 assigns joint efficiency from the joint type and the degree of radiographic examination. A Type 1 double-welded butt joint that is fully radiographed in accordance with UW-51 is assigned E equal to 1.00, while spot radiography yields 0.85 and no radiography yields 0.70.

Question 4ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

For a Section VIII Division 1 vessel made of carbon steel, what is the minimum permitted thickness of a formed shell or head, exclusive of corrosion allowance?

  1. 1/4 in
  2. 1/16 in Correct answer.
  3. 1/8 in
  4. 3/16 in

Explanation

UG-16(b) sets the minimum thickness of shells and heads after forming at 1/16 in (1.5 mm) for carbon and low alloy steel, with the corrosion allowance added on top of that value. Greater thickness may be required by the applicable design equations.

Question 5ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 vessel is fabricated of P-No. 1 carbon steel with carbon content not exceeding 0.30 percent. At what nominal thickness of the welded joint does postweld heat treatment become mandatory?

  1. 1-1/2 in Correct answer.
  2. 1/2 in
  3. 3/4 in
  4. 2 in

Explanation

UCS-56 Table UCS-56-1 requires postweld heat treatment of P-No. 1 carbon steel when the nominal thickness of the welded joint exceeds 1-1/2 in. Lower thresholds apply when the carbon content exceeds 0.30 percent, and certain exemptions in UCS-56 apply.

Question 6ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Which statement correctly describes the Section IV requirement for the safety valve or safety relief valve protecting a heating boiler?

  1. The set pressure shall be at least 90 percent of the hydrostatic test pressure
  2. The set pressure shall not exceed the boiler maximum allowable working pressure Correct answer.
  3. The set pressure may exceed the maximum allowable working pressure by 5 percent when two valves are installed
  4. The set pressure may exceed the maximum allowable working pressure if the Authorized Inspector witnesses the setting

Explanation

Section IV limits the setting of the required safety valve or safety relief valve to the maximum allowable working pressure or below, and the valve must have capacity sufficient to prevent the pressure from rising more than 6 percent above that pressure. No increase in setting is permitted to compensate for multiple valves or inspection practice.

Question 7ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Under UG-99 of Section VIII Division 1, the hydrostatic test of a vessel is normally conducted at what pressure, before applying the stress ratio correction?

  1. 2.0 times the MAWP
  2. 1.25 times the MAWP
  3. 1.5 times the MAWP
  4. 1.3 times the MAWP Correct answer.

Explanation

UG-99(b) bases the hydrostatic test on 1.3 times the maximum allowable working pressure, multiplied by the ratio of allowable stress at test temperature to allowable stress at design temperature. The 1.5 factor belongs to Section I boilers and Section IV heating boilers, a distinction inspectors frequently must apply.

Question 8ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Which form is the Manufacturer's Data Report for a completed boiler constructed to ASME Section I?

  1. Form P-3
  2. Form P-2 Correct answer.
  3. Form H-2
  4. Form U-1

Explanation

Section I requires the Manufacturer's Data Report on Form P-2 for a completed boiler, with Form P-3 used for parts and Form P-4 for certain other Section I items. Form U-1 belongs to Section VIII Division 1 and Form H-2 to Section IV heating boilers.

Question 9ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section I boiler shell has a longitudinal row of tube holes drilled on a pitch of 4.0 in, with each hole 2.5 in in diameter measured parallel to the pitch. What is the ligament efficiency between the tube holes, before comparison with the longitudinal joint efficiency?

  1. 0.375 Correct answer.
  2. 1.600
  3. 0.625
  4. 0.150

Explanation

Section I rules for tube holes in a longitudinal row express ligament efficiency as (p - d) divided by p, where p is the pitch and d is the hole diameter. Substituting 4.0 in and 2.5 in gives (4.0 - 2.5) / 4.0 = 0.375, which is then compared with the longitudinal joint efficiency and the lower value governs.

Question 10ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section I boiler has a maximum allowable working pressure of 1,000 psi. The allowable stress at design temperature is 17,500 psi and the allowable stress at test temperature is 20,000 psi. What minimum hydrostatic test pressure must the Authorized Inspector witness?

  1. 1,950 psi
  2. 1,714 psi Correct answer.
  3. 1,300 psi
  4. 1,500 psi

Explanation

PG-99.1 requires the hydrostatic test to be 1.5 times the maximum allowable working pressure multiplied by the ratio of allowable stress at test temperature to allowable stress at design temperature. Here 1.5 x 1,000 x (20,000 / 17,500) yields approximately 1,714 psi, which the Inspector verifies with the gauge and the Manufacturer's test procedure.

Question 11ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

In a Section VIII Division 1 vessel, the longitudinal seam of a cylindrical shell is classified as which weld joint category?

  1. Category B
  2. Category D
  3. Category A Correct answer.
  4. Category C

Explanation

Section VIII Division 1 categorizes welds by location and stress. A longitudinal seam in a shell is a Category A joint because it is a main shell weld carrying primary stress. Category B covers circumferential shell welds, while Categories C and D cover flange/tubesheet and nozzle attachment welds.

Question 12ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section I power boiler has a maximum allowable working pressure of 800 psi. What hydrostatic test pressure does PG-99 normally require?

  1. 800 psi
  2. 1,600 psi
  3. 1,200 psi
  4. 1,000 psi Correct answer.

Explanation

PG-99 requires the hydrostatic test to be conducted at 1.5 times the maximum allowable working pressure unless a specific exception applies. For an 800 psi boiler, the standard test pressure is therefore 1,200 psi. The test confirms pressure-tightness and structural integrity before the boiler is placed in service.

Question 13ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Under Section IV, what is the maximum allowable working pressure permitted for a hot water heating boiler?

  1. 30 psi
  2. 160 psi Correct answer.
  3. 15 psi
  4. 250 psi

Explanation

Section IV limits hot water heating boilers to a maximum allowable working pressure of 160 psi and a maximum temperature of 250°F. The 15 psi limit applies to steam heating boilers, not hot water boilers. These scope limits are fundamental to selecting the correct construction code.

Question 14ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 vessel is fabricated from P-No. 1 carbon steel. Postweld heat treatment is required when the nominal thickness at the weld exceeds which value?

  1. 1.25 in.
  2. 1.0 in.
  3. 0.75 in.
  4. 1.5 in. Correct answer.

Explanation

Table UCS-56-1 requires postweld heat treatment for P-No. 1 carbon steel when the nominal thickness at the weld exceeds 1 1/2 in. Below that threshold, PWHT is not mandatory under the table unless another rule or service condition imposes it. The thickness is measured at the weld being considered.

Question 15ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 cylindrical shell is designed for P = 150 psi, inside radius R = 30 in., allowable stress S = 13,800 psi, and joint efficiency E = 0.85. Using UG-27, what is the required thickness excluding corrosion allowance?

  1. 0.42 in.
  2. 0.35 in.
  3. 0.30 in.
  4. 0.39 in. Correct answer.

Explanation

UG-27 gives the required thickness for a cylindrical shell under internal pressure as t = PR/(SE - 0.6P). Substituting gives t = (150)(30)/[(13,800)(0.85) - 0.6(150)] = 4,500/11,640 = 0.387 in., which rounds to 0.39 in. Corrosion allowance, if any, would be added after this calculation.

Question 16ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 vessel has an inside diameter of 48 in. What is the minimum inspection opening required by UG-46?

  1. A handhole
  2. A manhole Correct answer.
  3. No inspection opening is required
  4. A sight glass

Explanation

UG-46 requires vessels with an inside diameter greater than 36 in. to be provided with at least one manhole. Handholes are the minimum for vessels over 12 in. through 36 in. inside diameter, and no inspection opening is required for vessels 12 in. and smaller.

Question 17ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 vessel has a minimum design metal temperature of -20°F. During hydrostatic testing under UG-99, the metal temperature must be at least what value?

  1. 10°F Correct answer.
  2. 50°F
  3. -50°F
  4. -20°F

Explanation

UG-99 requires the metal temperature during hydrostatic testing to be at least 30°F above the minimum design metal temperature, subject to the upper limit in the rule. Adding 30°F to -20°F gives a minimum test metal temperature of 10°F. This precaution reduces the risk of brittle fracture during the test.

Question 18ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

When a corrosion allowance is specified for a Section VIII Division 1 vessel, how is it applied in the design of a pressure part?

  1. It is added to the calculated pressure thickness. Correct answer.
  2. It is subtracted from the calculated thickness.
  3. It is used in place of the allowable stress.
  4. It is divided by the joint efficiency.

Explanation

The pressure thickness is first calculated from the applicable design formula using the design pressure, allowable stress, and joint efficiency. The specified corrosion allowance is then added to that calculated thickness before the nominal plate or component thickness is selected. This provides extra metal that may be consumed in service without reducing the pressure-retaining capability below design requirements.

Question 19ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 vessel has a 2:1 ellipsoidal head with internal design pressure P = 200 psi, inside diameter D = 60 in., allowable stress S = 15,000 psi, and joint efficiency E = 1.0. Using UG-32, what is the required thickness excluding corrosion allowance?

  1. 0.50 in.
  2. 0.40 in. Correct answer.
  3. 0.30 in.
  4. 0.24 in.

Explanation

For a 2:1 ellipsoidal head, UG-32 gives t = PD/(2SE - 0.2P). Substituting yields t = (200)(60)/[2(15,000)(1.0) - 0.2(200)] = 12,000/29,960 = 0.4005 in., which rounds to 0.40 in. The corrosion allowance would be added after this calculation.

Question 20ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 cylindrical shell has a thickness of 0.50 in., inside radius of 30 in., allowable stress of 15,000 psi, and joint efficiency of 0.85. Using UG-27, what is the maximum allowable working pressure?

  1. 210 psi Correct answer.
  2. 190 psi
  3. 240 psi
  4. 260 psi

Explanation

Rearranging the UG-27 cylindrical shell formula gives P = tSE/(R + 0.6t). Substituting yields P = (0.50)(15,000)(0.85)/[30 + 0.6(0.50)] = 6,375/30.3 = 210.4 psi, which rounds to 210 psi. The calculation applies to the longitudinal joint governing the shell thickness.

Question 21ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

An ASME Section I power boiler has 900 ft² of heating surface. What is the minimum number of safety valves required?

  1. Four
  2. Three
  3. Two Correct answer.
  4. One

Explanation

Section I requires at least one safety valve on each boiler and at least two when the heating surface exceeds 500 ft². Because 900 ft² is above that threshold, two safety valves are the minimum.

Question 22ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Which item is required to be shown on the nameplate of a vessel constructed to ASME Section VIII Division 1?

  1. Radiographic film density
  2. Minimum design metal temperature Correct answer.
  3. Welding procedure specification number
  4. Hydrostatic test pressure used by the fabricator

Explanation

UG-119 requires the nameplate to show the maximum allowable working pressure, design temperature, minimum design metal temperature, year built, manufacturer, and serial number. Hydrostatic test pressure and welding procedure details are not required nameplate markings.

Question 23ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Under UG-100 of Section VIII Division 1, the pneumatic test pressure is normally what multiple of the maximum allowable working pressure?

  1. 1.25
  2. 1.3
  3. 1.5
  4. 1.1 Correct answer.

Explanation

UG-100 sets the pneumatic test pressure at 1.1 times the maximum allowable working pressure, adjusted for test temperature where required. The 1.3 factor applies to the hydrostatic test under UG-99, not the pneumatic test.

Question 24ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Under ASME Section IV, what hydrostatic test pressure is required for a heating boiler?

  1. 1.25 times the maximum allowable working pressure
  2. 1.5 times the maximum allowable working pressure Correct answer.
  3. 1.3 times the maximum allowable working pressure
  4. 2.0 times the maximum allowable working pressure

Explanation

Section IV requires the hydrostatic test of a heating boiler at 1.5 times the maximum allowable working pressure. For a steam heating boiler with a 15 psi maximum allowable working pressure, the test pressure would be 22.5 psi.

Question 25ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

ASME Section I limits the allowable stress for carbon steel to the lower of which two values?

  1. Tensile strength divided by 4.0 and yield strength divided by 1.1
  2. Tensile strength divided by 3.5 and yield strength divided by 1.5 Correct answer.
  3. Tensile strength divided by 3.5 and yield strength divided by 1.0
  4. Tensile strength divided by 4.0 and yield strength divided by 1.5 at room temperature

Explanation

Section I establishes allowable stress as the lower of the specified minimum tensile strength divided by 3.5 and the specified minimum yield strength divided by 1.5 at design temperature. These factors provide the Code's required margins against tensile and yield failure.

Question 26ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Under UG-37 of Section VIII Division 1, what must reinforcement around an opening accomplish?

  1. Restore only the original shell thickness at the opening
  2. Increase the nozzle neck thickness until it equals the shell thickness
  3. Replace the area of material removed within UG-40 limits Correct answer.
  4. Add a reinforcing pad whose thickness equals the shell thickness

Explanation

UG-37 uses an area-replacement method: the reinforcement must replace the cross-sectional area removed by the opening, with credit for excess shell, nozzle neck, and pad material within UG-40 limits. Corrosion allowance and joint efficiency are included in the calculation.

Question 27ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

For an automatically fired steam boiler, ASME Section I requires a control that stops fuel firing when the water level falls below the lowest permissible water level. What is this device called?

  1. Low-water fuel cutoff Correct answer.
  2. Safety relief valve
  3. High-water alarm
  4. Flame scanner

Explanation

Section I requires an automatic low-water fuel cutoff for automatically fired steam boilers to stop fuel before the water level drops below the lowest permissible level. This is a water-level safety function, not a pressure-relief or flame-monitoring function.

Question 28ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A weld that attaches a nozzle neck to the cylindrical shell of a Section VIII Division 1 vessel is classified as which weld joint category?

  1. Category D Correct answer.
  2. Category A
  3. Category C
  4. Category B

Explanation

Section VIII Division 1 categorizes nozzle-to-shell and nozzle-to-head attachment welds as Category D joints. Category A is used for longitudinal shell seams, and Category B for circumferential seams.

Question 29ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

What is the minimum diameter of a circular manhole opening required for access to a Section I boiler?

  1. 11 in.
  2. 10 in.
  3. 12 in. Correct answer.
  4. 15 in.

Explanation

Section I requires inspection access; a circular manhole must be at least 12 in. in diameter. An oval manhole must be at least 11 in. by 15 in.

Question 30ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

For a torispherical head designed under UG-32 of Section VIII Division 1, what is the minimum required inside knuckle radius?

  1. The greater of 6% of the inside crown radius or 3 times the head thickness Correct answer.
  2. The larger of 10% of the inside crown radius or 3 times the head thickness, whichever is greater
  3. 6% of the inside crown radius only
  4. 3 times the head thickness only

Explanation

UG-32 requires the inside knuckle radius of a torispherical head to be at least 6% of the inside crown radius and at least 3 times the head thickness. The larger of those two values governs.

Question 31ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Under ASME Section IV, what is the maximum allowable working pressure permitted for a steam heating boiler?

  1. 15 psig Correct answer.
  2. 160 psig
  3. 30 psig
  4. 250 psig

Explanation

Section IV limits steam heating boilers to a maximum allowable working pressure of 15 psig; equipment intended to operate above that pressure falls under Section I power boiler rules. The 160 psig figure is the Section IV limit for hot water heating boilers, which is a separate provision. Because the limit is a scope boundary, exceeding it changes which code Section governs construction and stamping.

Question 32ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Which arrangement is permitted between a Section I power boiler and its safety valve?

  1. No valve of any description Correct answer.
  2. A check valve to prevent backflow
  3. A globe valve with the stem removed
  4. A gate valve locked in the open position

Explanation

Section I requires an unobstructed connection between the boiler and each safety valve, so no valve of any description may be installed in that line. This guarantees the valve can relieve the boiler at all times regardless of operator action or maintenance activity. The same principle governs the discharge side, which must remain open to the atmosphere.

Question 33ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A manufacturer constructs a pressure vessel to ASME Section VIII Division 1. Which symbol is applied to the vessel and its nameplate to indicate code compliance?

  1. U Correct answer.
  2. UM
  3. H
  4. S

Explanation

The "U" symbol is the Section VIII Division 1 certification mark applied by the manufacturer to the vessel and its nameplate. "S" denotes Section I power boilers, "H" Section IV heating boilers, and "UM" Section VIII Division 1 miniature vessels. The mark may be applied only under a quality control program accepted by the authorized inspection agency.

Question 34ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

Under Section I, safety valve capacity must be sufficient to prevent boiler pressure from rising more than what percentage above the maximum allowable working pressure while the valve is discharging?

  1. 20%
  2. 10%
  3. 3%
  4. 6% Correct answer.

Explanation

Section I requires the installed safety valve capacity to discharge all steam generated without allowing pressure to rise more than 6% above the maximum allowable working pressure. The 10% accumulation figure belongs to pressure relief valves on Section VIII vessels and must not be carried over to Section I boilers. Exceeding the accumulation limit demonstrates insufficient relieving capacity, and the valves must be resized or additional capacity provided.

Question 35ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 shell course is joined by a Type 1 double-welded butt joint. The joint receives spot radiographic examination in accordance with UW-11(a)(5). What joint efficiency applies to that joint under UW-12?

  1. 0.85 Correct answer.
  2. 0.90
  3. 1.00
  4. 0.70

Explanation

Table UW-12 assigns E = 1.00 to a Type 1 joint that is fully radiographed, 0.85 when only spot radiography is performed, and 0.70 when no radiography is performed. Spot radiography therefore qualifies the joint at 0.85 and never yields the full 1.00 value. The 0.90 value applies to a Type 2 joint that is fully radiographed, not to a Type 1 joint.

Question 36ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 cylindrical shell has a nominal thickness of 5/16 in. Under UG-36(c)(3), reinforcement is not required for a circular opening whose finished diameter does not exceed which value?

  1. 2 in.
  2. 2-3/8 in. Correct answer.
  3. 6 in.
  4. 3 in.

Explanation

UG-36(c)(3) exempts openings with a finished diameter not exceeding 2-3/8 in. from reinforcement in shells and heads not exceeding 3/8 in. thickness, provided the openings are not subject to rapid pressure fluctuations and the spacing rules are satisfied. Larger openings, or openings in thicker shells, must be reinforced in accordance with UG-37. The 2 in. value is the corresponding limit for shells thicker than 3/8 in.

Question 37ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 hemispherical head has an inside radius of 30 in., an internal design pressure of 150 psi, an allowable stress of 15,000 psi, and a joint efficiency of 1.00. Using UG-32, what is the minimum required thickness?

  1. 0.075 in.
  2. 0.100 in.
  3. 0.150 in. Correct answer.
  4. 0.300 in.

Explanation

UG-32(d) gives the hemispherical head thickness as t = PL/(2SE - 0.2P), where L is the inside radius. Substituting: 150 x 30 divided by (2 x 15,000 x 1.00 - 0.2 x 150) equals 4,500 divided by 29,970, or 0.150 in. Using the full diameter of 60 in. instead of the radius would double the result to about 0.300 in.

Question 38ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

During the hydrostatic test of a Section VIII Division 1 vessel, the indicating test gauge must have a dial range falling within which limits?

  1. 1.5 to 4 times the test pressure Correct answer.
  2. 2 to 3 times the test pressure
  3. 1 to 2 times the test pressure
  4. 1.5 to 3 times the test pressure

Explanation

UG-102 requires the indicating gauge used for the test to have a range of not less than 1-1/2 times and not more than 4 times the test pressure, so the reading falls in the mid-portion of the dial where accuracy is greatest. A gauge whose range is too close to the test pressure may be over-ranged during the test, while an oversized range loses reading resolution.

Question 39ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A nozzle neck is attached to a Section VIII Division 1 shell by a fillet weld. Under UW-16, the throat of that attaching weld shall be not less than which of the following?

  1. One-half the thickness of the shell
  2. The larger of 1/4 in. and 0.7 times the neck thickness
  3. The full thickness of the thinner part joined
  4. The smaller of 1/4 in. and 0.7 times the thickness of the thinner part joined Correct answer.

Explanation

UW-16 requires the throat of the attaching fillet weld to be at least the smaller of 1/4 in. and 0.7 t_min, where t_min is the thickness of the thinner of the parts joined at the joint. Using the smaller value prevents the rule from demanding a throat heavier than the joined parts can support. The 1/4 in. value controls only when the joined parts are thick enough that 0.7 t_min exceeds 1/4 in.

Question 40ASME Boiler and Pressure Vessel Code - Construction Requirements (Sections I, IV, VIII)

A Section VIII Division 1 shell course is 0.75 in. thick. Its longitudinal seam is fully radiographed (E = 1.00) and its circumferential seam is spot radiographed (E = 0.85). When required thickness is calculated with the UG-27(c)(2) equation for longitudinal stress, which joint efficiency applies?

  1. 0.925, the average of the two efficiencies
  2. 0.85, the efficiency of the circumferential seam Correct answer.
  3. 1.00, the efficiency of the longitudinal seam
  4. 0.70, the efficiency for an unradiographed joint

Explanation

Each UG-27(c) equation is paired with the joint whose efficiency reflects how the stress acts: the longitudinal stress equation uses the efficiency of the circumferential joint, while the circumferential stress equation uses the efficiency of the longitudinal joint. Here the circumferential seam is spot radiographed, so E = 0.85 enters the (c)(2) calculation. Averaging two joint efficiencies has no basis in UW-12.

Question 41NBIC Inspection, Repairs and Alterations

Under NBIC, which of the following activities is classified as an alteration rather than a repair?

  1. Weld build-up on a wasted area of a dished head
  2. Replacing a defective tube with one of the same size and material
  3. Adding a new nozzle opening to a pressure vessel Correct answer.
  4. Replacing a corroded shell section with material of the same specification and thickness

Explanation

NBIC distinguishes a repair, which restores a pressure-retaining item to a condition meeting the original code of construction, from an alteration, which changes the item's design. Adding a new nozzle opening changes the design configuration, so it is an alteration. Replacing a shell section or tube with identical material and performing weld build-up restore the original design and are repairs.

Question 42NBIC Inspection, Repairs and Alterations

In accordance with NBIC, who is authorized to perform repairs on a pressure-retaining item?

  1. A qualified welding contractor
  2. An ASME Code shop holding an S stamp
  3. A National Board R Certificate holder Correct answer.
  4. The owner-user's maintenance department

Explanation

NBIC requires repairs and alterations to pressure-retaining items to be performed by an organization holding a valid National Board R Certificate of Authorization. The Authorized Inspector verifies that the certificate is valid and covers the scope of work. Owner-user maintenance forces and welding contractors without the certificate are not authorized to perform NBIC repairs.

Question 43NBIC Inspection, Repairs and Alterations

NBIC Form R-1 is used to document which of the following?

  1. Manufacturer's data report for new construction
  2. Welder qualification record
  3. Owner's inspection record
  4. Report of repair or alteration Correct answer.

Explanation

NBIC Form R-1 is the Report of Repair or Alteration, completed by the repair organization and signed by the Authorized Inspector to record the scope of work and the inspections performed. New construction uses manufacturer's data reports, and welder qualification records document welder testing. The owner's inspection record is a separate in-service inspection document.

Question 44NBIC Inspection, Repairs and Alterations

Before repair welding begins, what is the Authorized Inspector's responsibility regarding welding procedure qualification?

  1. Writes the welding procedure specification
  2. Performs the procedure qualification test
  3. Certifies the welders' performance qualifications
  4. Reviews WPS and PQR compliance Correct answer.

Explanation

The Authorized Inspector verifies that the welding procedure specification is supported by a qualified procedure qualification record and that both comply with ASME Section IX for the materials and thicknesses involved. The Inspector does not author the WPS or perform the qualification testing; those are the repair organization's responsibilities. Welder performance qualifications are also verified, but the Inspector does not certify welders personally.

Question 45NBIC Inspection, Repairs and Alterations

After a weld repair is completed, when is post-weld heat treatment required under NBIC?

  1. Never, if a hydrostatic test is performed
  2. When the original code required PWHT for the material and thickness Correct answer.
  3. Only when the repair thickness exceeds one inch regardless of code
  4. Only when the owner specifically requests it

Explanation

NBIC requires post-weld heat treatment when the original code of construction required PWHT for the material and thickness involved, or when the repair procedure specifies it. There is no universal one-inch threshold that overrides the original code. A hydrostatic test does not substitute for PWHT, and PWHT is a code requirement rather than an owner option.

Question 46NBIC Inspection, Repairs and Alterations

When is a pressure test required after an alteration under NBIC?

  1. Only alterations to boilers require a hydrostatic test
  2. An alteration affecting pressure integrity requires a test Correct answer.
  3. No pressure test is required when NDE is performed
  4. Every repair requires a hydrostatic test

Explanation

When an alteration affects pressure-retaining integrity, NBIC requires a hydrostatic or pneumatic test in accordance with the original code of construction and applicable NBIC requirements. Routine repairs do not automatically require a hydrostatic test when the repair scope and NDE demonstrate integrity. NDE does not automatically waive a required pressure test for an alteration.

Question 47NBIC Inspection, Repairs and Alterations

Repairs to pressure relief devices must be performed by which of the following?

  1. A VR Certificate holder Correct answer.
  2. The owner-user's maintenance staff
  3. An ASME U stamp holder
  4. An R Certificate holder

Explanation

NBIC requires repairs to pressure relief devices to be performed by an organization holding a valid National Board VR Certificate of Authorization. The VR program covers the repair, assembly, and testing of pressure relief devices. An R Certificate holder is not automatically authorized to repair pressure relief devices unless it also holds VR authorization.

Question 48NBIC Inspection, Repairs and Alterations

What is the Authorized Inspector's role in nondestructive examination of a repair?

  1. Verifies NDE procedures and reviews results Correct answer.
  2. Waives NDE when the repair is small
  3. Personally performs all NDE on the repair
  4. Requires NDE only for alterations

Explanation

The Authorized Inspector does not normally perform NDE personally; the repair organization performs it using qualified personnel and written procedures. The Inspector verifies that the NDE method, procedure, and personnel qualifications meet NBIC and code requirements, and reviews the results before signing the repair report. NDE cannot be omitted simply because a repair is small.

Question 49NBIC Inspection, Repairs and Alterations

Before an alteration begins, what must the Authorized Inspector do with the repair organization's written procedure?

  1. Delegates approval to the welder
  2. Approves the procedure after the repair is complete
  3. Performs the repair personally
  4. Reviews and approves the procedure before work Correct answer.

Explanation

NBIC requires the repair organization to prepare a written repair or alteration procedure, and the Authorized Inspector must review and accept it before work begins. This prior review allows the Inspector to confirm that materials, welding, NDE, heat treatment, and testing will meet the applicable requirements. The Inspector does not perform the repair or delegate approval to production personnel.

Question 50NBIC Inspection, Repairs and Alterations

What does the Authorized Inspector's signature on Form R-1 signify?

  1. The item is new construction
  2. The jurisdiction has waived future inspections
  3. The repair organization is financially responsible
  4. The work was inspected and complies with NBIC Correct answer.

Explanation

The Authorized Inspector's signature on Form R-1 certifies that the repair or alteration was inspected and found to comply with the applicable NBIC requirements and the original code of construction. It is an inspection certification, not a financial allocation or a waiver of future jurisdictional inspections. The completed form becomes part of the item's permanent record.