Hydraulics Fluid Power. + 4&8

Question 1

What are the major areas of fluid power?

Answer 1

Hydraulic and pneumatic (air)

Question 2

What is a Fluid Distribution System?

Answer 2

All systems that utilize a fluid but not for power transmission purposes

Question 3

Define a fluid.

Answer 3

A substance that will flow into the shape of its container and exert a pressure

Question 4

What is a characteristic of a fluid regarding compression?

Answer 4

A fluid cannot be compressed

Question 5

What is the shape of a gas?

Answer 5

A gas has no fixed shape and completely fills and takes the shape of its container

Question 6

What determines the volume of a gas?

Answer 6

The pressure it is exposed to

Question 7

What is matter?

Answer 7

A material that occupies space and has weight

Question 8

List the three basic forms of matter.

Answer 8

• Solids
• Liquids
• Gasses

Question 9

What is a molecule?

Answer 9

The smallest particle of a substance that can be divided into and still maintain the characteristics of that substance

Question 10

What does a liquid subjected to a force seek?

Answer 10

The path of least resistance and its own level

Question 11

What is mass?

Answer 11

A measure of the amount of material in a body, not affected by gravity

Question 12

Define weight.

Answer 12

The pull of gravity on a body

Question 13

What is density?

Answer 13

The weight per unit of volume of a substance

Question 14

How is density measured?

Answer 14

In a ratio of weight to its volume

Question 15

What is specific gravity?

Answer 15

A ratio of how many times heavier a substance is compared to water

Question 16

What is the equation for area in relation to diameter?

Answer 16

A = .7854D²

Question 17

What does the equation P = FA represent?

Answer 17

Pressure equals force times area

Question 18

What is pressure?

Answer 18

Force per unit of area (lbs/sq in)

Question 19

True or False: Pumps create pressure.

Answer 19

False

Question 20

What causes fluids to exert pressure?

Answer 20

The weight of the fluid above the point where pressure is being determined

Question 21

What increases pressure due to weight in a fluid?

Answer 21

Depth of the liquid and its density

Question 22

What is Pascal’s Law?

Answer 22

Pressure on a confined fluid is transmitted undiminished in all directions

Question 23

List the three ways pressure can be created.

Answer 23

• Weight of a column of fluid
• Force applied on a confined fluid
• Resistance to flow

Question 24

What is a vacuum?

Answer 24

Any pressure less than atmospheric pressure

Question 25

What causes flow in a fluid system?

Answer 25

Any pressure difference

Question 26

Define orifice.

Answer 26

A restricted passage in a pipe or valve used to control flow or create a pressure drop

Question 27

What factors determine the amount of flow through an orifice?

Answer 27

* Size of the orifice * Viscosity of the fluid * The pressure drop

Question 28

What does Archimedes' Principle state?

Answer 28

A body submerged wholly or partially in a fluid is buoyed up by a force equal to the weight of the fluid displaced

Question 29

If an object's specific gravity is less than the liquid, what happens?

Answer 29

The object will float

Question 30

What happens when an object sinks in a liquid?

Answer 30

It displaces a volume of liquid equal to the object's volume

Question 31

What does Boyle's Law state?

Answer 31

The volume of a confined body of gas varies inversely as the absolute pressure, provided temperature remains unchanged

Question 32

What is solubility?

Answer 32

The ability of one substance to dissolve into another

Question 33

What is cavitation?

Answer 33

When the pressure drops, some of the air dissolved in the oil will come back out

Question 34

Define valve.

Answer 34

A mechanical device consisting of a body and a moving part that connects and disconnects passages within the body

Question 35

What does a pressure switch do?

Answer 35

Controls anything electrical (ON/OFF)

Question 36

What is a safety relief valve?

Answer 36

A valve body with inlet and exhaust passages and an internal moving part, not intended to be operated frequently

Question 37

What is the function of a pressure regulator?

Answer 37

Reduces flow downstream and controls flow downstream

Question 38

What is a double acting cylinder?

Answer 38

Has a port on each end of the cylinder, allowing air pressure to enter or exhaust

Question 39

What does a needle valve do?

Answer 39

Causes a restriction to control flow

Question 40

What is a Direction Control Valve (DCV)?

Answer 40

A valve that controls the direction of flow

Question 41

What are the types of ways to move valves?

Answer 41

* Manual * Mechanical * Electrical * Pilot Pressure

Question 42

What is a 2-way valve?

Answer 42

Consists of two ports connected to each other with passages which are connected and disconnected

Question 43

What is a 3-way valve?

Answer 43

Consists of 3 ports connected with passages and has the ability to exhaust pressure

Question 44

What does a 4-way valve do?

Answer 44

Causes powered reversible motion of a cylinder or motor

Question 45

What are detents used for?

Answer 45

To hold and keep the movable member(s) in the desired shifted position