Industrial Hydraulics Technician Level 2
Practice Exam Questions And Correct
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Rationales 2026 Q&A | Instant Download
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1. A hydraulic system operates at a pressure of 2000 psi. A cylinder with a
piston area of 4 in² is extending. What force does the cylinder develop?
a) 500 lb
b) 2000 lb
c) 4000 lb
d) 8000 lb
Correct answer: d) 8000 lb
Force = Pressure × Area. 2000 psi × 4 in² = 8000 lb.
2. Which component converts hydraulic energy into linear mechanical motion?
a) Hydraulic pump
b) Flow control valve
c) Hydraulic cylinder
d) Accumulator
Correct answer: c) Hydraulic cylinder
A hydraulic cylinder converts fluid power into linear force and motion. A
pump converts mechanical energy into hydraulic energy, a flow control valve
regulates flow, and an accumulator stores energy.
3. A gear pump delivers 10 GPM at 1500 psi. What is the theoretical hydraulic
horsepower?
a) 2.6 HP
b) 8.7 HP
, c) 15.0 HP
d) 26.2 HP
Correct answer: b) 8.7 HP
Hydraulic HP = (Flow in GPM × Pressure in psi) / 1714. (10 × 1500) / 1714 ≈
8.75 HP.
4. What is the primary function of a relief valve in a hydraulic system?
a) Maintain a constant flow rate
b) Limit maximum system pressure
c) Divert flow to a second circuit
d) Reduce pressure in a branch circuit
Correct answer: b) Limit maximum system pressure
A relief valve opens to protect the system from overpressure by diverting fluid
to the tank. It does not regulate flow or reduce branch pressure; that’s the
role of pressure-reducing or flow-control valves.
5. An ISO symbol showing a square with a diagonal arrow through it represents
which component?
a) Fixed-displacement pump
b) Variable-displacement pump
c) Pressure-relief valve
d) Check valve
Correct answer: b) Variable-displacement pump
The diagonal arrow across a pump or motor symbol indicates variability,
meaning displacement can be adjusted. A fixed-displacement pump lacks the
arrow. A check valve uses a ball and seat symbol.
6. A technician notices milky-colored hydraulic oil. What is the most likely
cause?
a) Aerated oil
b) Water contamination
c) Oxidation
d) Additive depletion
Correct answer: b) Water contamination
, Milky appearance indicates emulsified water. Air-entrained oil appears foamy
or bubbles rise. Oxidation darkens the oil and may cause a burnt smell.
7. Which type of hydraulic pump is best suited for high-pressure, variable-
displacement applications?
a) External gear pump
b) Vane pump
c) Axial piston pump
d) Centrifugal pump
Correct answer: c) Axial piston pump
Axial piston pumps can handle high pressure (above 5000 psi) and are easily
made variable-displacement by changing the swashplate angle. Gear and
vane pumps are typically fixed-displacement or less efficient at very high
pressures.
8. What is the purpose of a counterbalance valve?
a) Prevent shock when a directional valve shifts
b) Provide a back pressure to prevent a load from free-falling
c) Sequence two actuators in a predetermined order
d) Unload the pump at low pressure during idle
Correct answer: b) Provide a back pressure to prevent a load from free-
falling
A counterbalance valve creates a resisting pressure on the return side of a
cylinder to control overrunning loads. It is essentially a pilot-operated relief
valve that maintains back pressure proportional to load-induced pressure.
9. In a hydraulic schematic, what does a triangle with the apex pointing
towards the pump indicate?
a) Pneumatic line
b) Drain line
c) Pressure port
d) Return line to tank
Correct answer: c) Pressure port
A solid triangle pointing in the direction of flow indicates a pressure line,
, often the pump outlet. A hollow triangle may indicate pneumatic, but apex
direction is key; hydraulic pressure lines use a filled triangle.
10.A double-acting cylinder with a 3-inch bore and 1.5-inch rod extends at a
velocity of 4 in/s. Flow entering the cap end is 20 GPM. What is the return
flow from the rod end (approx.)?
a) 10 GPM
b) 15 GPM
c) 20 GPM
d) 25 GPM
Correct answer: b) 15 GPM
Cap area = π(3²)/4 = 7.07 in², rod area = π(1.5²)/4 = 1.77 in², annulus area =
5.30 in². Extend flow 20 GPM ≈ 77.1 in³/s gives velocity 77.1/7.07 = 10.9 in/s
(not needed). Return flow Q_return = Q_cap × (annulus area / cap area) = 20
× (5.30/7.07) ≈ 15 GPM. Alternatively, rod-end flow equals cap flow minus
rod volume displaced: Q - (rod area × velocity). Works out to about 15 GPM.
11.What is the main advantage of a pressure-compensated flow control valve?
a) It maintains constant flow regardless of load pressure changes
b) It varies flow proportionally to load pressure
c) It eliminates the need for a relief valve
d) It allows reverse flow freely
Correct answer: a) It maintains constant flow regardless of load pressure
changes
A pressure-compensated flow control keeps flow constant even if load
pressure varies, by adjusting an internal restrictor to compensate for
pressure drop changes across the orifice.
12.Which ISO cleanliness code format indicates the number of particles greater
than 4 µm, 6 µm, and 14 µm per milliliter?
a) ISO 4406: 18/16/13
b) ISO 4407
c) NAS 1638 Class 6
d) ISO 11171
Practice Exam Questions And Correct
Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download
1. A hydraulic system operates at a pressure of 2000 psi. A cylinder with a
piston area of 4 in² is extending. What force does the cylinder develop?
a) 500 lb
b) 2000 lb
c) 4000 lb
d) 8000 lb
Correct answer: d) 8000 lb
Force = Pressure × Area. 2000 psi × 4 in² = 8000 lb.
2. Which component converts hydraulic energy into linear mechanical motion?
a) Hydraulic pump
b) Flow control valve
c) Hydraulic cylinder
d) Accumulator
Correct answer: c) Hydraulic cylinder
A hydraulic cylinder converts fluid power into linear force and motion. A
pump converts mechanical energy into hydraulic energy, a flow control valve
regulates flow, and an accumulator stores energy.
3. A gear pump delivers 10 GPM at 1500 psi. What is the theoretical hydraulic
horsepower?
a) 2.6 HP
b) 8.7 HP
, c) 15.0 HP
d) 26.2 HP
Correct answer: b) 8.7 HP
Hydraulic HP = (Flow in GPM × Pressure in psi) / 1714. (10 × 1500) / 1714 ≈
8.75 HP.
4. What is the primary function of a relief valve in a hydraulic system?
a) Maintain a constant flow rate
b) Limit maximum system pressure
c) Divert flow to a second circuit
d) Reduce pressure in a branch circuit
Correct answer: b) Limit maximum system pressure
A relief valve opens to protect the system from overpressure by diverting fluid
to the tank. It does not regulate flow or reduce branch pressure; that’s the
role of pressure-reducing or flow-control valves.
5. An ISO symbol showing a square with a diagonal arrow through it represents
which component?
a) Fixed-displacement pump
b) Variable-displacement pump
c) Pressure-relief valve
d) Check valve
Correct answer: b) Variable-displacement pump
The diagonal arrow across a pump or motor symbol indicates variability,
meaning displacement can be adjusted. A fixed-displacement pump lacks the
arrow. A check valve uses a ball and seat symbol.
6. A technician notices milky-colored hydraulic oil. What is the most likely
cause?
a) Aerated oil
b) Water contamination
c) Oxidation
d) Additive depletion
Correct answer: b) Water contamination
, Milky appearance indicates emulsified water. Air-entrained oil appears foamy
or bubbles rise. Oxidation darkens the oil and may cause a burnt smell.
7. Which type of hydraulic pump is best suited for high-pressure, variable-
displacement applications?
a) External gear pump
b) Vane pump
c) Axial piston pump
d) Centrifugal pump
Correct answer: c) Axial piston pump
Axial piston pumps can handle high pressure (above 5000 psi) and are easily
made variable-displacement by changing the swashplate angle. Gear and
vane pumps are typically fixed-displacement or less efficient at very high
pressures.
8. What is the purpose of a counterbalance valve?
a) Prevent shock when a directional valve shifts
b) Provide a back pressure to prevent a load from free-falling
c) Sequence two actuators in a predetermined order
d) Unload the pump at low pressure during idle
Correct answer: b) Provide a back pressure to prevent a load from free-
falling
A counterbalance valve creates a resisting pressure on the return side of a
cylinder to control overrunning loads. It is essentially a pilot-operated relief
valve that maintains back pressure proportional to load-induced pressure.
9. In a hydraulic schematic, what does a triangle with the apex pointing
towards the pump indicate?
a) Pneumatic line
b) Drain line
c) Pressure port
d) Return line to tank
Correct answer: c) Pressure port
A solid triangle pointing in the direction of flow indicates a pressure line,
, often the pump outlet. A hollow triangle may indicate pneumatic, but apex
direction is key; hydraulic pressure lines use a filled triangle.
10.A double-acting cylinder with a 3-inch bore and 1.5-inch rod extends at a
velocity of 4 in/s. Flow entering the cap end is 20 GPM. What is the return
flow from the rod end (approx.)?
a) 10 GPM
b) 15 GPM
c) 20 GPM
d) 25 GPM
Correct answer: b) 15 GPM
Cap area = π(3²)/4 = 7.07 in², rod area = π(1.5²)/4 = 1.77 in², annulus area =
5.30 in². Extend flow 20 GPM ≈ 77.1 in³/s gives velocity 77.1/7.07 = 10.9 in/s
(not needed). Return flow Q_return = Q_cap × (annulus area / cap area) = 20
× (5.30/7.07) ≈ 15 GPM. Alternatively, rod-end flow equals cap flow minus
rod volume displaced: Q - (rod area × velocity). Works out to about 15 GPM.
11.What is the main advantage of a pressure-compensated flow control valve?
a) It maintains constant flow regardless of load pressure changes
b) It varies flow proportionally to load pressure
c) It eliminates the need for a relief valve
d) It allows reverse flow freely
Correct answer: a) It maintains constant flow regardless of load pressure
changes
A pressure-compensated flow control keeps flow constant even if load
pressure varies, by adjusting an internal restrictor to compensate for
pressure drop changes across the orifice.
12.Which ISO cleanliness code format indicates the number of particles greater
than 4 µm, 6 µm, and 14 µm per milliliter?
a) ISO 4406: 18/16/13
b) ISO 4407
c) NAS 1638 Class 6
d) ISO 11171
