Free NCCER Industrial Boilermaker – Maintenance knowledge assessment Practice Questions

Sample Practice Questions

Try these 10 sample questions from the NCCER Industrial Boilermaker – Maintenance knowledge assessment practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1During maintenance welding, a vessel cannot be moved, but nearby combustible supplies can. What is the required fire-prevention step for those supplies?

   1. A. Move the supplies to a safe place before welding begins.
   2. B. Cover the supplies with guards while leaving them in place.
   3. C. Wet the supplies in place and begin welding after inspection.
   4. D. Post a fire watch beside the supplies throughout welding.

   Answer: A

   Explanation: For an immovable workpiece, OSHA says, "all movable fire hazards in the vicinity shall be taken to a safe place." The supplies can be moved, so the boilermaker must move them before welding.

   Reference: OSHA 29 CFR 1910.252 — General requirements — 29 CFR 1910.252(a)(1)(i)

2. 2A boilermaker is about to weld a heat-exchanger shell plate held in a shop fixture. Where should the arc welder's work lead be firmly attached?

   1. A. To the shell plate being welded
   2. B. To the separate fixture holding the shell
   3. C. To the welding bench under the fixture
   4. D. To the nearby structural steel frame

   Answer: A

   Explanation: OSHA requires, "The work lead shall be firmly attached to the work" before welding. In this setup the shell plate is the work; the fixture, bench, and adjacent frame are separate conductors.

   Reference: OSHA 29 CFR 1910.254 — Arc welding and cutting — 29 CFR 1910.254(d)(2)

3. 3After dismantling a bolted flange, a boilermaker reviews the FSA's general instruction against gasket reuse. Which construction is its expressly stated exception to that blanket instruction?

   1. A. Grooved metal gasket with covering layers
   2. B. Spiral-wound gasket with a filler strip
   3. C. Compressed-fiber sheet gasket
   4. D. Solid-metal ring-joint gasket

   Answer: A

   Explanation: The FSA says, "With the exception of grooved metal gaskets with covering layers, do not reuse gaskets under any circumstances." It names only the covered grooved-metal construction as an exception; that wording does not itself guarantee that a particular used gasket is fit for reuse.

   Reference: Fluid Sealing Association Gasket Handbook — Chapter 4, Installation of the Gasket and Assembly of the BJFA, p. 113

4. 4A gate valve on a maintenance line is considered for flow regulation by adjusting stem travel. Where does DOE say most of the flow change occurs?

   1. A. Near the shutoff position
   2. B. Near the mid-stroke position
   3. C. Near the fully open position
   4. D. Evenly over the full stroke

   Answer: A

   Explanation: DOE states, "Most of the flow change occurs near shutoff" for a gate valve. Its nonlinear flow response makes mid-stroke, near-open, and uniform-change descriptions inaccurate.

   Reference: DOE Fundamentals Handbook: Mechanical Science, Volume 2 — Module 4, Gate Valves, p. 9

5. 5Before using a boiler assembly drawing to identify parts for maintenance, the boilermaker needs to confirm the drawing's identity and validity. Which drawing area provides that information?

   1. A. The title block
   2. B. The drawing grid
   3. C. The notes legend
   4. D. The revision cloud

   Answer: A

   Explanation: DOE states, "The title block of a drawing ... contains all the information necessary to identify the drawing and to verify its validity." It is the starting place for identifying the print.

   Reference: DOE Fundamentals Handbook: Engineering Symbology, Prints, and Drawings, Volume 1 — Module 1, The Title Block, p. 2

6. 6A wire-rope sling leg for lifting a vessel section is nearly vertical. Under OSHA's general-industry definition, what is the largest angle off vertical that may still be treated as vertical loading?

   1. A. 2 degrees
   2. B. 5 degrees
   3. C. 10 degrees
   4. D. 15 degrees

   Answer: B

   Explanation: OSHA defines angle of loading and says "an angle of loading of five degrees or less from the vertical may be considered a vertical angle of loading." Five degrees is therefore the largest qualifying deviation.

   Reference: OSHA 29 CFR 1910.184 — Slings — 29 CFR 1910.184(b), Definitions

7. 7A boilermaker reads a threaded pipe spool drawing calling for a general-purpose American standard taper pipe thread. Which thread designation matches that callout?

   1. A. NPSC
   2. B. NPTR
   3. C. NPSM
   4. D. NPT

   Answer: D

   Explanation: The NBS pipe-thread handbook identifies "NPT— American Standard taper pipe threads for general use." NPSC and NPSM are straight-thread designations, while NPTR is for railing joints.

   Reference: NBS Handbook H28, Part II — Pipe Threads — Section VII.1, Types of Pipe Threads, p. 1

8. 8A boilermaker opens the channel of a shell-and-tube exchanger and needs to identify the plate at the tube ends that separates the tube-side fluid from the shell-side fluid. What component is it?

   1. A. Tubesheet
   2. B. Transverse baffle
   3. C. Channel cover
   4. D. Pass partition

   Answer: A

   Explanation: The DOE handbook states, "At the ends of the heat exchanger, the tube-side fluid is separated from the shell-side fluid by a tube sheet." That identifies the plate encountered at the ends of the tubes.

   Reference: DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 2 — Heat Transfer, Heat Exchangers, p. 31

9. 9A maintenance weld must be made on a fixed vessel. A nearby combustible structure also cannot be moved. How should the boilermaker protect that structure from the hot work?

   1. A. Assign a fire watch to stand immediately beside the structure.
   2. B. Use guards to confine heat, sparks, and slag from the structure.
   3. C. Sweep the surrounding floor and leave the structure exposed.
   4. D. Position a portable extinguisher adjacent to the structure.

   Answer: B

   Explanation: OSHA states that when the object and fire hazards cannot be moved, "guards shall be used to confine the heat, sparks, and slag, and to protect the immovable fire hazards." A fire watch or extinguisher does not replace the specified guards for this condition.

   Reference: OSHA 29 CFR 1910.252 — General requirements — 29 CFR 1910.252(a)(1)(ii)

10. 10A long arc welding cable is still coiled beside the welding machine. What should the boilermaker do before using it?

    1. A. Spread out the cable to limit overheating and insulation damage.
    2. B. Tighten the coil to keep the cable clear of the floor.
    3. C. Suspend the coil from a nearby pipe support.
    4. D. Place the coil beneath the welding machine.

    Answer: A

    Explanation: OSHA directs, "Coiled welding cable shall be spread out before use to avoid serious overheating and damage to insulation." This applies before the worker starts the weld.

    Reference: OSHA 29 CFR 1910.254 — Arc welding and cutting — 29 CFR 1910.254(d)(2)