Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Final > Pneumatics > Flashcards

Pneumatics Flashcards

1
Q

In a pneumatic system what must be present at all times for the system to function

A

Force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

When you add gauge pressure to atmospheric pressure you get

A

Absolute pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Force x distance in feet or inches equals

A

Foot pounds or inch pounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

A physical law dealing with heat is Charles law, it says if the volume of a confined quantity of gas remains the same,

A

The change in the pressure of the gas varies directly with a change in the absolute temperature of the gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

A principal of leverage states that for every force increase there is a corresponding movement what

A

Decrease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

As temperatures increase the molecules bump into each other more frequently while they are moving, which gives them a greater resistance to flow this is called

A

Dynamic viscosity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Positive displacement compressors do what

A

Confine the air and compress it by decreasing the volume of the space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Dynamic compressors do what

A

Accelerate the air with rapidly turning rotor blades

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Less power is needed to compress air because what is used between stages

A

Inter cooler, cooling between stages reduces the volume of air that is compressed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does lube oil do

A

Reduce friction and improve heat transfer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is unloading a compressor

A

Relieving all internal pressure, so it starts easier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Single stage vane compressors can develop up to how much psi

A

50 psi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Wet type rotary screw compressors do not use

A

Timing gears

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The impeller compressor is designed for what

A

High volume rather than high pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Two disadvantages of centrifugal compressors are that they

A

Require more horsepower and that they operate at very high speeds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Four control methods of a centrifugal compressor is what

A

Speed variation, suction throttling, discharge throttling, and recirculation, the most efficient tho is speed variation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The recommended method of cleaning dry filters are

A

To use recommended solvent to clean

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The amount of moisture or water vapor that exists in free air depends on the temp and weather conditions. The amount of moisture in the air at anytime compared to the amount of water vapor the air could hold if it were completely saturated is referred to as

A

Relative humidity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Water cooled compressors are used with

A

Large compressors or medium sized compressors that run for more than eight hours a day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

After coolers are built strong because why

A

They operate at high pressures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Most systems or aftercoolers have what to remove moister

A

Mechanical separators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Deliquescent is what

A

Desiccant used to absorb moisture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Air receivers do what

A

There most important purpose is their ability to store compressed air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is used as a pre filter to pick up large dirt particles

A

Inertial separators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Absolute rating in reference to a filter is

A

It’s ability to stop 100% dirt particles

26
Q

Closely packed fine metallic wire is used in what type of filter

A

Depth filter

27
Q

Wetted filters cost more than dry filters but

A

They can be cleaned and reused many times

28
Q

Fine lubricators mist oil and are used for

A

Long distances complicated piping and systems with intermittent equipment operation

29
Q

Lubricators should be mounted blank the pressure regulator

A

After

30
Q

Turbulent flow creates

A

Heat

31
Q

How to avoid turbulence

A

Inner walls of air line should be smooth and with the least amount of bends possible

32
Q

Pressure loss in a pipe is affected by

A

Airflow volume, pipe diameter, and the air pressure

33
Q

Airflow at lower pressures is affected blank by friction

A

More

34
Q

Npt threads seal how

A

Flank to flank (side to side) contact with the air of pipe dope

35
Q

Compressor discharge and distribution lines should slope 1 inch for every

A

10 feet, the slope should be downward in the direction of air flow

36
Q

Control valves are identified how

A

Number of connecting ports, type of control element, method of operation, number of control positions

37
Q

A needle valve is made is excellent at

A

High pressure service but has high pressure losses

38
Q

A plunger controls the entire air flow through a valve in what kind of valve

A

Direct acting normally closed two way solenoid valve

39
Q

Spoil valves are great, why

A

Easy to operate even at high pressures, they can be made to shift to more than one position

40
Q

Three way valves may be used how

A

Diverter or selector valves, holding valves, and directional valves. The only difference is how they are hooked up

41
Q

Four way valves are used to

A

Simplify pneumatic circuits

42
Q

A five way valve is

A

A special four way valve with an extra exhaust port

43
Q

A pressure control valve is done how

A

Unloading, holding back or blocking open the valve ports

44
Q

Relief valves are located where

A

Between the pressure reg and the individual piece of equipment, it protects from full outlet line pressure if the regulator fails

45
Q

Cracking pressure is adjusted how

A

By adjusting the spring

46
Q

Diaphragm valves respond much faster than poppet valves because

A

The compressed air works on a much larger pressure sensitive area (a diaphragm)

47
Q

Pressure relief valves do what

A

Only job is to protect the system and its components from damage

48
Q

Pressure regulators sometimes have what built in

A

A relief valve

49
Q

Pneumatic cylinders do not require what

A

Air lines to return air to the receiver

50
Q

Which side of the piston has less pressure on it

A

The rod side

51
Q

A single acting cylinder is equipped with

A

An internal spring

52
Q

An exhaust flow control metering valve prevents the cylinder from experience what

A

Shock

53
Q

Pivoted cylinder mountings are classed as being

A

Trunnions or clevis and have no rigid support

54
Q

Capacity coefficient is what

A

A control valves ability to handle the air of a cylinder

55
Q

The valve port size should be what than the cylinder port size

A

No smaller, equal

56
Q

Pneumatic motors need a starting or break a way force called

A

Torque

57
Q

Positive displacement motors are usually the

A

Fixed displacement type

58
Q

Maximum power output is obtained at what speed

A

Medium speed and medium torque output

59
Q

The horsepower output of pneumatic motors is the product of the shaft…

A

Speed and torque

60
Q

Starting torque is what

A

Is the turning force the motor exerts from a dead stop typically 75% of the stalling torque, this means it’s really hard to stall the motor

61
Q

The thrust of the piston causes the wobble (cam) plate to

A

Rotate, this motion is transferred through gears to the output shaft

62
Q

The force applied to the hydraulic fluid is spread over a smaller area so it creates what

A

Greater pressure ( pressure multiplier )

Final (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions