1.Before entering a robotic work cell for maintenance?
- A.Slow robot to min speed
- B.Full lockout/tagout, isolate all energy✓
- C.Unplug teach pendant only
- D.Inform operator
Why: Full LOTO of all energy sources. Robots can move unexpectedly if not completely de-energized.
2.Centrifugal pump cavitating — most likely cause?
- A.Discharge pressure too low
- B.Insufficient NPSHa (suction restriction)✓
- C.Impeller too large
- D.Motor running backwards
Why: Cavitation: NPSHa < NPSHr. Causes: clogged suction, high suction lift, high fluid temp, restricted suction piping.
3.Excessive discharge temp in reciprocating compressor — causes?
- A.Oversized motor
- B.Worn rings, broken valves, insufficient cooling✓
- C.Inlet filter too clean
- D.Tank too large
Why: Worn piston rings (recirculation), broken valves, fouled cooler, low oil. Can cause oil ignition from carbon buildup.
4.Pipe schedule number indicates:
- A.Pipe length
- B.Wall thickness✓
- C.Outside diameter
- D.Thread count
Why: Schedule (40, 80, etc.) = wall thickness for given nominal size. Higher schedule = thicker = higher pressure rating.
5.Screw conveyor vibrating with grinding noise — inspect:
- A.Motor nameplate
- B.Flights, trough wear, hanger bearings✓
- C.Drive belt only
- D.Discharge opening only
Why: Check: worn flights contacting trough, worn liner, seized hanger bearings, bent screw sections, foreign objects.
6.Hydraulic balancing of a multi-stage centrifugal pump's rotor is commonly achieved by:
- A.Grinding down alternating impellers
- B.Arranging impellers back-to-back so their axial thrusts oppose and cancel✓
- C.Adding more bearings only
- D.Increasing impeller diameter
Why: Opposing impeller arrangement is a standard way to balance out the cumulative axial thrust that would otherwise build up in a multistage pump.
7.An internal gear pump's crescent-shaped divider serves to:
- A.Increase pump speed
- B.Isolate the inlet (suction) port from the outlet (discharge) port✓
- C.Cool the pumped fluid
- D.Balance the rotor axially
Why: The crescent seal separates the expanding suction pocket from the contracting discharge pocket as the inner and outer gears rotate.
8.If the inside diameter of a pipe is doubled while flow rate stays constant, fluid velocity will:
- A.Double
- B.Stay the same
- C.Be reduced to one quarter✓
- D.Be reduced to one half
Why: Cross-sectional area scales with diameter squared, so velocity (which is inversely proportional to area at constant flow) drops to 1/4.
32 more Material Handling / Process Systems questions inside
Plus a timed 433A exam simulator, spaced-repetition review of every question you get wrong, and an AI tutor you can ask “why?”.
Start free — 20 questions a day →RedSeal Prep Pro is an independent study tool. Practice questions are original content written in the style of the Certificate of Qualification and are not affiliated with the Red Seal Program, the Industrial Mechanic (Millwright) trade board, or any provincial certification body.