CWEA Mechanical Technologist Grade
3 Exam Questions and Correct
Answers (Verified Answers) Plus
Rationales 2026 Q&A
1.
Q: What is the primary function of a centrifugal pump in a wastewater facility?
A. Increase solids content
B. Move water or wastewater through the system
C. Remove dissolved oxygen
D. Filter sludge
Answer: B
Rationale: Centrifugal pumps are used to transport liquids by converting rotational energy into
flow and pressure.
2.
Q: What is cavitation in a pump system?
A. Excess lubrication
B. Formation and collapse of vapor bubbles in a pump
C. Increased discharge pressure
D. Solid buildup in pipes
Answer: B
Rationale: Cavitation occurs when vapor bubbles form due to low pressure and collapse,
potentially damaging pump components.
3.
Q: Which instrument is used to measure flow rate in a pipeline?
A. Thermometer
B. Flow meter
,C. Tachometer
D. Hydrometer
Answer: B
Rationale: Flow meters are specifically designed to measure the rate of fluid movement.
4.
Q: What is the purpose of a check valve?
A. Increase flow
B. Prevent backflow
C. Measure pressure
D. Reduce turbulence
Answer: B
Rationale: Check valves allow flow in one direction only, preventing reverse flow.
5.
Q: What does NPSH stand for in pump operation?
A. Net Pump Suction Head
B. Net Positive Suction Head
C. Negative Pressure System Height
D. Normal Pump Speed Handling
Answer: B
Rationale: NPSH is the pressure available at the pump suction to avoid cavitation.
6.
Q: What is the primary purpose of lubrication in mechanical equipment?
A. Increase friction
B. Reduce wear and heat between moving parts
C. Increase vibration
D. Clean pipes
Answer: B
Rationale: Lubrication reduces friction, wear, and overheating in mechanical systems.
, 7.
Q: What is a common symptom of pump misalignment?
A. Reduced vibration
B. Excessive vibration and noise
C. Increased flow efficiency
D. Lower temperature
Answer: B
Rationale: Misalignment causes uneven rotation, leading to vibration and noise.
8.
Q: What is the function of a mechanical seal in a pump?
A. Increase flow rate
B. Prevent leakage along the shaft
C. Filter solids
D. Measure pressure
Answer: B
Rationale: Mechanical seals prevent fluid from leaking where the shaft exits the pump housing.
9.
Q: Which material is commonly used for pump impellers in wastewater applications?
A. Wood
B. Cast iron or stainless steel
C. Paper
D. Rubber only
Answer: B
Rationale: Durable metals like cast iron and stainless steel resist corrosion and abrasion.
10.
3 Exam Questions and Correct
Answers (Verified Answers) Plus
Rationales 2026 Q&A
1.
Q: What is the primary function of a centrifugal pump in a wastewater facility?
A. Increase solids content
B. Move water or wastewater through the system
C. Remove dissolved oxygen
D. Filter sludge
Answer: B
Rationale: Centrifugal pumps are used to transport liquids by converting rotational energy into
flow and pressure.
2.
Q: What is cavitation in a pump system?
A. Excess lubrication
B. Formation and collapse of vapor bubbles in a pump
C. Increased discharge pressure
D. Solid buildup in pipes
Answer: B
Rationale: Cavitation occurs when vapor bubbles form due to low pressure and collapse,
potentially damaging pump components.
3.
Q: Which instrument is used to measure flow rate in a pipeline?
A. Thermometer
B. Flow meter
,C. Tachometer
D. Hydrometer
Answer: B
Rationale: Flow meters are specifically designed to measure the rate of fluid movement.
4.
Q: What is the purpose of a check valve?
A. Increase flow
B. Prevent backflow
C. Measure pressure
D. Reduce turbulence
Answer: B
Rationale: Check valves allow flow in one direction only, preventing reverse flow.
5.
Q: What does NPSH stand for in pump operation?
A. Net Pump Suction Head
B. Net Positive Suction Head
C. Negative Pressure System Height
D. Normal Pump Speed Handling
Answer: B
Rationale: NPSH is the pressure available at the pump suction to avoid cavitation.
6.
Q: What is the primary purpose of lubrication in mechanical equipment?
A. Increase friction
B. Reduce wear and heat between moving parts
C. Increase vibration
D. Clean pipes
Answer: B
Rationale: Lubrication reduces friction, wear, and overheating in mechanical systems.
, 7.
Q: What is a common symptom of pump misalignment?
A. Reduced vibration
B. Excessive vibration and noise
C. Increased flow efficiency
D. Lower temperature
Answer: B
Rationale: Misalignment causes uneven rotation, leading to vibration and noise.
8.
Q: What is the function of a mechanical seal in a pump?
A. Increase flow rate
B. Prevent leakage along the shaft
C. Filter solids
D. Measure pressure
Answer: B
Rationale: Mechanical seals prevent fluid from leaking where the shaft exits the pump housing.
9.
Q: Which material is commonly used for pump impellers in wastewater applications?
A. Wood
B. Cast iron or stainless steel
C. Paper
D. Rubber only
Answer: B
Rationale: Durable metals like cast iron and stainless steel resist corrosion and abrasion.
10.
