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NCCER Millwright practice questions

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Question 1Safety

On a construction site where overhead hazards exist, which head protection practice is required of a millwright?

  1. Wear a soft cap under a welding helmet at all times
  2. Wear a hard hat that meets the applicable ANSI standard Correct answer.
  3. Wear a bump cap when the task lasts more than one hour
  4. Wear a hard hat only while heavy equipment is running

Explanation

Head protection is required wherever there is a risk of falling objects, bumping against fixed objects, or contact with electrical conductors. The hard hat must meet the ANSI Z89.1 performance standard and be worn with the brim forward unless the manufacturer states otherwise. It must be inspected for cracks and replaced after a significant impact.

Question 2Safety

Which practice best describes acceptable housekeeping on a millwright job site?

  1. Clearing walkways and keeping them free of scrap and debris Correct answer.
  2. Stacking scrap plate in the walkway until the end of shift
  3. Running cords across aisles so they can be seen easily
  4. Leaving oil spills to dry so the floor is not slippery

Explanation

Good housekeeping means work areas, walkways, and stairs are kept clear of scrap, tools, and material that could cause trips or falls. Debris is removed as work progresses rather than saved for the end of the shift. Spills are cleaned up immediately and cords are routed overhead or covered.

Question 3Safety

Where does a millwright find detailed information about a chemical's hazards, protective measures, and first aid?

  1. In the project schedule posted at the site trailer
  2. In the manufacturer's warranty packet for the tool
  3. In the safety data sheet kept at the work location Correct answer.
  4. On the shipping label attached to the outside of the drum

Explanation

The Hazard Communication standard requires that a safety data sheet for each hazardous chemical be readily accessible to workers in their work area. The label is only a summary of the key hazards and does not contain first aid or exposure control detail. Workers must be trained on how to read both the label and the SDS before using the product.

Question 4Safety

Who is authorized to give hand signals that direct a crane operator's movements during a lift?

  1. Only the designated signal person for that lift Correct answer.
  2. Any journeyman millwright working in the area
  3. Any worker who has a clear view of the load
  4. The rigger who hooked the load to the sling

Explanation

The crane operator takes directional signals only from the person designated as the signal person for that operation. All crew members should know and use the standard hand signals so communication is consistent. Anyone may give an emergency stop signal, but routine movement commands come from the designated signal person.

Question 5Safety

Which practice is acceptable when using hand tools?

  1. Striking a wrench with a hammer to break a nut loose
  2. Carrying a sharp chisel in your pocket while climbing
  3. Using a pipe as a cheater bar to gain extra leverage
  4. Pulling a wrench toward you instead of pushing it away Correct answer.

Explanation

A wrench should be pulled rather than pushed when possible, so that if the fastener slips the hand moves away from the work instead of into it. Tools must be used only for the purpose they were designed for. Impact tools and sharp-edged tools are carried in a pouch or tool belt, never in a pocket.

Question 6Safety

Before lifting a heavy pump component by hand, what should a millwright do first?

  1. Bend at the waist and hold the load away from your body
  2. Size up the load and use help or a lifting aid if needed Correct answer.
  3. Twist while lifting so the load clears nearby piping
  4. Hold your breath and lift quickly to protect your lower back

Explanation

Manual lifting starts with an assessment of the load's weight, shape, and path of travel. If the load is too heavy or awkward, the worker gets assistance or uses a hoist, cart, or other mechanical aid. The lift itself is done with the legs, back straight, load close to the body, and no twisting.

Question 7Safety

A millwright has locked out a conveyor and gone home at the end of the shift. Who may remove that lock?

  1. The next millwright scheduled to work on the conveyor
  2. Any electrician on site who verifies the power is off
  3. Only the worker who applied it, per site procedure Correct answer.
  4. The shift supervisor who has the department key

Explanation

Each worker applies a personal lock and keeps the only key, so the lock is removed only by the person who installed it. If that worker is unavailable, the employer's documented lockout removal procedure must be followed, which normally includes verifying the worker is not in the area. Supervisors and other trades may not simply cut or remove someone else's lock.

Question 8Safety

Before a millwright enters a permit-required confined space, which set of controls must be in place?

  1. Verbal approval from the crew working nearby
  2. A gas monitor worn by the entrant alone
  3. A flashlight, a hard hat, and a two-way radio
  4. An entry permit, atmospheric testing, and an attendant Correct answer.

Explanation

A permit-required confined space entry requires a completed entry permit, pre-entry and continuous atmospheric testing, an attendant stationed outside, and rescue provisions. The entrant also uses a retrieval system where feasible. Verbal permission from coworkers does not satisfy any of these requirements.

Question 9Safety

On a construction site, fall protection is generally required when a worker is exposed to an unprotected edge at what height above a lower level?

  1. 15 ft (4.6 m) or more above a lower level
  2. 10 ft (3 m) or more above a lower level
  3. 20 ft (6.1 m) or more above a lower level
  4. 6 ft (1.8 m) or more above a lower level Correct answer.

Explanation

In general construction work, employees exposed to falls of 6 feet or more to a lower level must be protected by guardrails, safety nets, or a personal fall arrest system. Some specific tasks and equipment have different thresholds, so the site fall protection plan governs. The 6-foot trigger applies to most millwright work at elevation.

Question 10Safety

A pre-use inspection reveals a wire rope sling with broken wires and a crushed section. What is the correct action?

  1. Remove it from service and tag it as defective Correct answer.
  2. Reduce the rated capacity by half and proceed
  3. Cut off the damaged end and continue using it
  4. Use it for one more light lift and then tag it

Explanation

Any sling showing damage such as broken wires, crushing, kinking, or a missing identification tag must be immediately removed from service. It is tagged as defective and returned to a qualified person for repair or destruction so it cannot be picked up by mistake. Field modifications or derating by the user are never allowed.

Question 11Safety

When using a portable extinguisher on a small flammable liquid fire, where should the nozzle be aimed?

  1. At the base of the fire, sweeping side to side Correct answer.
  2. Above the fire so the agent settles down on it
  3. At the middle of the flames to cool the vapor
  4. At the top of the flames so they are smothered

Explanation

The extinguishing agent must reach the burning fuel surface, so the nozzle is aimed at the base of the fire and swept side to side. Aiming at the flames wastes agent and allows the fire to keep growing. The PASS sequence covers pull, aim, squeeze, and sweep.

Question 12Safety

Why must portable electric tools on a construction site be connected to a ground-fault circuit interrupter?

  1. It limits the current a tool can draw under load
  2. It trips quickly when current leaks to ground Correct answer.
  3. It raises the voltage so tools run cooler under load
  4. It converts AC power to DC for safer operation

Explanation

A GFCI senses small differences between the current leaving and returning through the circuit, which indicates current leaking to ground. It opens the circuit fast enough to prevent a fatal shock. GFCIs do not change voltage, convert power, or limit normal running current.

Question 13Safety

Before welding or cutting near combustible materials, a millwright must first:

  1. Notify the supplier of the welding consumables
  2. Open all doors so the smoke can escape the building
  3. Obtain a hot work permit and post a fire watch Correct answer.
  4. Wet down the floor and begin work immediately

Explanation

Hot work outside a designated area requires a permit issued by the site authority after combustibles are moved or protected. A fire watch is posted during the work and maintained for a period afterward to catch smoldering material. Wetting a floor does not replace combustible removal, the permit, or the fire watch.

Question 14Safety

For each 4 feet of working length, how far should the base of a straight ladder be set out from the wall?

  1. 2 ft (0.6 m) from the wall
  2. 1 ft (0.3 m) from the wall Correct answer.
  3. 4 ft (1.2 m) out from the base of the wall
  4. 3 ft (0.9 m) from the wall

Explanation

The 4-to-1 rule sets the base one quarter of the working length away from the wall, so a ladder reaching 16 feet up is set 4 feet out. This angle keeps the climber's weight over the base and reduces the chance of the ladder tipping backward. The ladder also must be secured against movement and extend 3 feet above the landing.

Question 15Safety

What is the standard height range for the top guardrail of a supported scaffold platform?

  1. About 12 to 18 in. (30 to 46 cm)
  2. About 24 to 30 in. (61 to 76 cm)
  3. About 48 to 54 in. (122 to 137 cm)
  4. 38 to 45 in. (97 to 114 cm) Correct answer.

Explanation

The top edge of the toprail on a supported scaffold is installed between roughly 38 and 45 inches above the platform surface. A midrail is placed about halfway between the toprail and the platform. Guardrails must be able to withstand the required load without failing.

Question 16Safety

A millwright must run a laser alignment check on a coupling that has to stay energized. What is the best control for the exposed rotating shaft?

  1. Guard the shaft so no part of the body can reach it Correct answer.
  2. Place a warning tag on the disconnect and proceed
  3. Ask a coworker to watch the shaft during the work
  4. Wear gloves and keep hands clear of the rotating shaft

Explanation

When a machine must run during alignment, an engineering control such as a fixed guard or barrier is the most reliable protection because it prevents contact entirely. PPE and warning tags rely on human behavior and do not stop entanglement. A spotter cannot react fast enough to prevent a caught sleeve or glove.

Question 17Safety

A millwright must enter a 5 ft deep utility trench to inspect a pipe support. Where should the excavated spoil be placed?

  1. At least 2 ft back from the edge of the excavation Correct answer.
  2. As close to the trench as the spoil pile will sit
  3. Inside the trench along one wall as a toe board
  4. Right at the edge so it is easy to backfill later

Explanation

Spoil, equipment, and materials must be kept at least 2 feet back from the edge of an excavation so they do not overload the walls or fall in on workers. A trench 5 feet deep also requires a protective system such as sloping, shoring, or a trench box. Access and egress within 25 feet of travel is also required.

Question 18Safety

How must oxygen and fuel gas cylinders be stored at a job site?

  1. Inside a locked room with the regulators left attached
  2. Separated by 20 ft or a 5 ft noncombustible barrier Correct answer.
  3. Chained together upright against the same wall
  4. Lying side by side in a closed wooden crate

Explanation

Oxygen and fuel gas cylinders are kept apart by at least 20 feet or by a noncombustible barrier at least 5 feet high with a fire rating of at least half an hour. Cylinders are stored upright, secured, and have valve protection caps installed with regulators removed. This separation prevents a fuel gas leak from finding an oxygen-enriched atmosphere.

Question 19Safety

In a boom-supported aerial lift, where should a millwright attach the fall protection lanyard?

  1. To the manufacturer's designated anchor in the basket Correct answer.
  2. To the mid-rail of the basket, which is closest
  3. To the nearest overhead structural steel beam in the area
  4. To a sling wrapped loosely around the boom of the lift

Explanation

Fall protection in an aerial lift is attached only to the anchor point the manufacturer provides, which is engineered for the arresting forces involved. Anchoring to structure outside the basket can cause the lift to tip or the worker to be pulled out during a boom movement. Rails and boom sections are not rated anchorages.

Question 20Safety

Atmospheric testing shows oxygen at 17 percent inside a tank. What does this reading mean for entry?

  1. It shows an oxygen-enriched space that needs ventilation first
  2. It is acceptable for short entries under 15 minutes
  3. It is acceptable if the entrant wears a dust mask
  4. It is oxygen deficient; entry needs supplied-air protection Correct answer.

Explanation

Normal air is about 20.9 percent oxygen, and a confined space must test between 19.5 and 23.5 percent before entry. A reading of 17 percent is oxygen deficient and can cause impaired judgment and loss of consciousness. Entry then requires ventilation and supplied-air respiratory protection, not a dust mask or a time limit.

Question 21Tools and Equipment

A torque wrench should be backed off to its lowest setting after use primarily to:

  1. Keep the scale markings from fading
  2. Stop the ratchet from reversing direction
  3. Remove residual lubricant from the head
  4. Protect the spring from taking a set Correct answer.

Explanation

A stored torque wrench left at a working setting keeps its internal spring compressed, and over time the spring takes a permanent set that throws the calibration off. Backing the adjuster down to the lowest graduation relaxes the spring between uses. The practice has nothing to do with the markings, the ratchet direction, or lubrication.

Question 22Tools and Equipment

A feeler gauge is the correct tool for measuring:

  1. The clearance between two parts Correct answer.
  2. Outside diameter of a shaft
  3. Angle of a chamfer
  4. Depth of a drilled hole

Explanation

Feeler gauge blades are precision-thickness strips used to check the gap between mating or moving surfaces, such as valve lash, spark plug gaps, or shaft end play. The blade that fits with a slight drag indicates the clearance. Diameters, depths, and angles each require a different measuring tool.

Question 23Tools and Equipment

A 0-1 in. outside micrometer has 25 divisions on the thimble. The sleeve shows the 0.250 in. graduation exposed and the thimble line on 12. What is the reading?

  1. 0.362 in.
  2. 0.262 in. Correct answer.
  3. 0.250 in.
  4. 0.237 in.

Explanation

The sleeve carries the large graduations at 0.025 in. intervals, and each thimble division adds 0.001 in. Adding 0.250 in. from the sleeve to 12 x 0.001 in. from the thimble gives 0.262 in. The two readings are added, never subtracted.

Question 24Tools and Equipment

While a shaft is rotated one full turn, a dial indicator graduated in 0.001 in. sweeps from a low to a high point spanning 8 divisions. The total indicated runout is:

  1. 0.016 in.
  2. 0.008 in. Correct answer.
  3. 0.004 in.
  4. 0.0008 in.

Explanation

Total indicated runout is the full spread of the needle over one revolution, so 8 divisions multiplied by 0.001 in. per division equals 0.008 in. The value is not halved; half the total spread describes eccentricity, which is a different quantity. Doubling or shifting the decimal point has no basis.

Question 25Tools and Equipment

Compared with rim-and-face dial indicator alignment, laser shaft alignment mainly removes:

  1. Indicator sag and bracket deflection Correct answer.
  2. The need to record readings
  3. The need to perform a soft foot check
  4. The amount of shim required under the feet

Explanation

Laser systems measure straight through the coupling gap and calculate the alignment mathematically, so the deflection and sag that affect a long indicator bracket no longer corrupt the result. The machine still must be checked for soft foot, shimmed as needed, and documented. Only the measurement error source is eliminated.

Question 26Tools and Equipment

Hydraulic torque wrenches are chosen over manual torque multipliers for large flange bolting mainly because they:

  1. Eliminate the need for a reaction arm
  2. Work without a socket on any bolt head
  3. Eliminate the need for calibration
  4. Deliver high, repeatable torque with less operator effort Correct answer.

Explanation

A hydraulic wrench uses fluid pressure to generate very high torque with consistent, repeatable output and far less physical effort than a manual multiplier. The pressure-to-torque relationship is predictable and verifiable. It still requires a properly seated socket and a restrained reaction point.

Question 27Tools and Equipment

A snatch block is used in a rigging setup to:

  1. Redirect a pull and gain mechanical advantage Correct answer.
  2. Join two wire rope ends together
  3. Measure tension in a loaded sling leg
  4. Protect a sling from sharp corners on the load

Explanation

A snatch block lets a line be opened and laid into the sheave without threading an end, so the pull can be redirected or reeved for a mechanical advantage. Its sheave carries the rope while the shackle or hook attaches to the anchor. It does not measure, cushion, or connect rope ends.

Question 28Tools and Equipment

Two sling legs support a load. If the included angle between the legs is opened from 60 degrees to 120 degrees, the tension in each leg:

  1. It decreases as the included angle opens
  2. It stays the same regardless of the angle
  3. It increases as the included angle opens Correct answer.
  4. It increases only when the load shifts

Explanation

Leg tension equals load divided by two times the cosine of half the included angle. As the included angle opens, the cosine of half the angle drops and the tension rises. At a 120 degree included angle each leg carries a tension equal to the full load weight.

Question 29Tools and Equipment

Before a new vitrified grinding wheel is mounted on a bench grinder, the operator must:

  1. Soak the wheel in oil overnight
  2. Perform a ring test to check for cracks Correct answer.
  3. True the wheel with a diamond dresser
  4. Run the wheel at full speed for ten minutes

Explanation

A ring test is a tap test in which a sound wheel gives a clear ring and a cracked wheel gives a dull thud. It is done before mounting because a cracked wheel can burst at operating speed. Dressing is done after the wheel is mounted and running true.

Question 30Tools and Equipment

A cutting torch tip that is too small for the plate thickness being cut will:

  1. Cut slowly and may fail to pierce the plate Correct answer.
  2. Have no measurable effect on cut quality
  3. Cut faster with a narrower kerf
  4. Give a smoother cut with less slag

Explanation

The tip size sets the volume of cutting oxygen and the preheat capacity. An undersized tip cannot supply enough oxygen for the kerf, so travel speed drops and the cut may not penetrate at all. Slag, ragged edges, and lost cuts are typical results.

Question 31Tools and Equipment

Which tap is used to bring threads all the way to the bottom of a blind hole?

  1. Plug tap
  2. Bottoming tap Correct answer.
  3. Taper tap
  4. Pipe tap

Explanation

A bottoming tap has very little chamfer, so it can cut threads close to the bottom of a blind hole. It is normally run in after a taper or plug tap has started and advanced the threads. Pipe taps are for tapered pipe threads and are not used to finish a straight blind hole.

Question 32Tools and Equipment

A hand reamer should be rotated:

  1. Clockwise, then reversed to withdraw
  2. Clockwise only, withdrawn without reversing Correct answer.
  3. In either direction at low speed
  4. Counterclockwise to break the chips

Explanation

Hand reamers are cut to work in one direction only, so they are turned clockwise to size the hole. They are pulled straight out while still turning clockwise; reversing loads the cutting edges on their back side and can dull them or oversize the hole. Chips are cleared by withdrawing the tool, not by back-turning.

Question 33Tools and Equipment

An induction bearing heater is preferred over a torch for installing a bearing on a shaft because it:

  1. Cools the shaft for a shrink fit
  2. Permanently expands the bore oversize
  3. Heats the bearing evenly without flame Correct answer.
  4. Removes the need for a shoulder

Explanation

An induction heater magnetically induces current in the bearing so it warms uniformly with no open flame and with a controlled, measurable temperature. Uniform expansion lets the bearing slip onto the shaft and then shrink back to the correct fit. The expansion is temporary and the shaft shoulder is still required.

Question 34Tools and Equipment

Precision levels used for aligning millwright machinery are graduated in:

  1. Degrees of arc per inch
  2. Ounces per foot of length
  3. Radians per foot of run
  4. Thousandths of an inch per foot Correct answer.

Explanation

Machine levels are graduated in slope units such as 0.0005 in. per foot per division, which lets the millwright convert bubble movement into shim thickness at a given foot spacing. This direct length-per-length reading matches how shims are added. Angular and weight-based units do not convert to shim thickness as directly.

Question 35Tools and Equipment

A plumb bob is used to establish:

  1. The torque value of a bolt
  2. A true vertical line Correct answer.
  3. The center of a bolt circle
  4. A horizontal reference line

Explanation

A plumb bob hangs on a cord and, under gravity, defines a true vertical reference from the suspension point down to the point below. It is used to transfer a point or check verticality of a column or shaft. Horizontal work is done with a level, and layout circles with dividers.

Question 36Tools and Equipment

A torque multiplier with a 4:1 ratio is driven by a torque wrench set to 100 ft-lb, and the reaction arm is properly restrained. Ignoring friction losses, the torque applied to the bolt is:

  1. 104 ft-lb
  2. 400 ft-lb Correct answer.
  3. 25 ft-lb
  4. 100 ft-lb

Explanation

A multiplier increases the input torque by its ratio, so 100 ft-lb multiplied by 4 equals 400 ft-lb at the output. The reaction arm must be restrained against a solid point so the body of the tool does not spin. The wrench setting is multiplied, not divided or added.

Question 37Tools and Equipment

An impact wrench is the wrong tool to use when you need to:

  1. Apply final torque to critical joints Correct answer.
  2. Remove rusted or seized nuts
  3. Drive lag bolts into timber
  4. Run pin-retained impact sockets

Explanation

Impact wrenches deliver hammering torque that is not accurately controlled, so they cannot establish a specified final preload on a critical joint. Final tightening must be done with a calibrated torque wrench or a controlled torque device. Removal work, driving fasteners, and use with impact-rated sockets are all normal applications.

Question 38Tools and Equipment

When drilling a large hole in a steel plate on a drill press, the work should be:

  1. Held by hand to feel the cut
  2. Resting on a wooden block
  3. Aligned by eye before drilling
  4. Clamped to the table Correct answer.

Explanation

A drill press can grab and spin loose work, so the workpiece must be clamped to the table or held in a vise bolted or clamped down. A wooden backup board may support the exit side but does not secure the plate by itself. Hand holding and eyeballing layout are both unsafe and inaccurate.

Question 39Tools and Equipment

Indicator bar sag is measured by:

  1. Zeroing on the shaft and rotating 90 degrees
  2. Mounting the setup on a rigid stationary bar Correct answer.
  3. Comparing top and bottom rim readings
  4. Checking the indicator with a gauge block

Explanation

Sag is the deflection of the indicator bracket and bar under their own weight. It is found by supporting the same bracket and indicator on a rigid, stationary bar and reading how far the needle moves as the assembly is rotated. That value is then applied as a correction to the actual alignment readings.

Question 40Tools and Equipment

When a bearing is a press fit on a shaft and must be removed with a jaw puller, the pulling force should be applied to:

  1. Both races alternately
  2. The outer race
  3. The cage or shield
  4. The inner race Correct answer.

Explanation

Pull on the component that carries the interference fit. Because the inner race is gripped on the shaft, force goes there and the rolling elements are never used to transmit the pulling load. Pulling through the outer race or cage brinells the races and ruins the bearing.

Question 41Blueprints, Schematics, and Layout

On an orthographic view, an edge that exists on the part but cannot be seen from that viewing direction is shown using which line?

  1. A thin continuous line with arrowheads at each end
  2. A heavy cutting-plane line with arrows
  3. A center line of long and short dashes
  4. A line of short, evenly spaced dashes Correct answer.

Explanation

Hidden lines are drawn as short, evenly spaced dashes and represent edges that exist on the part but are not visible in a given view. Visible edges are drawn as solid object lines.

Question 42Blueprints, Schematics, and Layout

A plan drawing is marked SCALE 1/4" = 1'-0". A wall measures 3-1/2 inches on the drawing. What is the actual length of the wall?

  1. 8 ft 9 in
  2. 42 ft 0 in
  3. 3 ft 6 in
  4. 14 ft 0 in Correct answer.

Explanation

At a scale of 1/4 in = 1 ft, every inch on the paper represents 4 ft of actual length. Multiplying 3.5 in by 4 ft/in gives 14 ft.

Question 43Blueprints, Schematics, and Layout

In third-angle projection, where is the top view drawn in relation to the front view?

  1. Below the front view
  2. To the right of the front view
  3. Above the front view Correct answer.
  4. To the left of the front view

Explanation

Third-angle projection places each view on the side of the front view from which it is observed, as if the object sits inside a glass box and each face is projected onto the glass beside it. The top view therefore goes above the front view.

Question 44Blueprints, Schematics, and Layout

A center line is drawn through a circular bolt pattern. What does that line locate?

  1. The limits of a section cut
  2. The hidden internal edges
  3. The axis or center of holes and symmetrical features Correct answer.
  4. The machined surfaces of the part

Explanation

Center lines are thin chain lines of alternating long and short dashes used to locate axes, hole centers, bolt circles, and planes of symmetry. They establish where features are centered, not the size of edges.

Question 45Blueprints, Schematics, and Layout

In a standard isometric drawing, the three principal axes are drawn how?

  1. One vertical and two at 45 degrees above the horizontal
  2. One vertical and two at 30 degrees above the horizontal Correct answer.
  3. Three axes spaced 60 degrees apart in the plane of the paper
  4. One horizontal and two at 60 degrees to it

Explanation

A true isometric has one vertical axis and two receding axes drawn at 30 degrees above the horizontal, spaced 120 degrees apart. Equal distances along all three axes represent true length.

Question 46Blueprints, Schematics, and Layout

A dimension on a drawing reads 12.50 plus or minus 0.02. What range of sizes will be accepted?

  1. 12.30 to 12.70
  2. 12.50 to 12.52
  3. 12.48 to 12.52 Correct answer.
  4. 12.48 to 12.50

Explanation

A plus-or-minus tolerance is applied in both directions from the nominal size. Subtracting 0.02 gives the low limit of 12.48 and adding 0.02 gives the high limit of 12.52.

Question 47Blueprints, Schematics, and Layout

A feature control frame contains the letters A, B, and C in its datum compartments. What do these letters identify?

  1. The datum features from which the tolerance zone is located Correct answer.
  2. The basic dimensions used to locate the feature
  3. The number of repeated features being controlled
  4. The allowable material condition for the tolerance

Explanation

Datum reference letters in a feature control frame tie the tolerance zone to specific datum features on the part, in a stated order of precedence. They must match the datum feature symbols placed on the drawing.

Question 48Blueprints, Schematics, and Layout

A hole callout reads 2X 0.500 DIA THRU. What does this specify?

  1. Two holes 0.500 in. deep, blind
  2. One hole counterbored in two steps
  3. Two holes of 0.500 in. diameter drilled completely through the part Correct answer.
  4. A single hole having two different diameters

Explanation

The prefix 2X gives the number of holes, the diameter symbol with 0.500 gives their size, and THRU means each hole passes completely through the material.

Question 49Blueprints, Schematics, and Layout

On a welding symbol, a fillet weld symbol drawn below the reference line calls for the weld to be made where?

  1. On the other side of the joint
  2. In the field during erection
  3. On the arrow side of the joint Correct answer.
  4. On both sides of the joint

Explanation

The reference line divides the symbol: a weld symbol below the line applies to the arrow side of the joint, and one above the line applies to the other side. Symbols on both sides call for welds on both sides.

Question 50Blueprints, Schematics, and Layout

In a section view, the closely spaced diagonal hatching lines across an area indicate what?

  1. A cavity or void inside the part
  2. A surface that must be machined after assembly
  3. Solid material cut by the cutting plane Correct answer.
  4. A fastener that is not sectioned

Explanation

Hatching (section lining) fills the areas of a section view that represent solid material intersected by the cutting plane. Openings and voids are left unhatched.