INTRODUCTION TO FLUID POWER

Describe the primary function of a hydraulic fluid.

• Lubrication

• Sealing

• Power transmission

• Contaminant removal

Label the ISO symbol?

• Fixed pump

• Variable pump

• Variable motor

• Fixed motor

Predict on the most common liquid that is used as a medium in fluid power systems is

• Synthetic fluids

• Petroleum-based mineral oil

• Emulsions

• Biodegradable hydraulic fluids

Select which of the following correctly states how the viscosities of a liquid and a gas will change with temperature?

• Viscosity increases with the increase in temperature of a liquid and decreases with the increase in temperature of a gas

• Viscosity increases with the increase in temperature of a liquid and increases with the increase in temperature of a gas

• Viscosity decreases with the increase in temperature of a liquid and increases with the increase in temperature of a gas

• Viscosity decreases with the increase in temperature of a liquid and decreases with the increase in temperature of a gas

The Bernoulli's equation is based on the assumption that

• There is no loss of energy of the liquid flowing

• The velocity of flow is uniform across any cross-section of the pipe

• No force except gravity acts on the fluid

• All the above

For which of the following purpose hydraulic film acts as a seal between the machined cavity and spool?

• To reduce leakage

• For cooling purposes

• For lubrication purposes

• All the above

Why is fluid power preferred in mobile vehicles?

1. Power can be transmitted without any delay

2. When overloaded, fluid power systems stop without

damaging the components

3. Speed variation cannot be achieved

4. Fluid is non-compressible

• 1 and 4

• 2, 3 and 4

• 1, 2 and 4

• 1, 2 and 3

Which of the following reasons make water unsuitable to use as a fluid in hydraulic systems?

1. Poor lubrication

2. High viscosity

3. More leakage

4. Quickly evaporates

• 1 and 3

• 2 and 4

• 1, 2 and 4

• 1, 3 and 4

The neutralization number is a measure of the---------------- of hydraulic oil.

Rust is a chemical reaction between iron or steel and --------- .