In a pneumatic system, force must be present at all times for the system to function. What is this force?
Compressed Air
What is the formula for work?
Work = Force x Piston Travel
What does Charles law state?
If the volume of a confined quantity of gas remains the same, the change in the pressure of the gas varies directly with a change in absolute temperature of the gas.
If the original force is applied to the large piston instead of to the small piston, the force exerted on the small piston?
Decreases, but it’s amount of travel increases.
If the kinetic energy increases and the total energy remains the same, the potential energy of the air moving in a reduced flow passage is reduced. If the potential energy is reduced…
The pressure of the air is also reduced.
Positive-displacement compressors that are capable of compressing air to relatively high pressures are commonly used in pneumatic power systems. What is one kind of these devices?
Reciprocating Piston
What opens the valves on a reciprocating compressor?
The negative pressure allows the air at atmospheric pressure to open the valves.
What do cooling components allow for in compressors?
The need for less power because the cooling between stages reduces the volume of air that is compressed in the second stage.
What are the two functions of compressor lubricating oil?
Reduce friction and improve the transfer of heat in the compressor.
What does unloading allow for in large compressors?
It does not compress air and is easier to start.
Single stage vane compressors are capable of developing up to what psi discharge pressure?
50 PSI
What speeds do screw compressors operate at?
Between 3,000 and 12,000 RPM
Impeller compressor also knows as blowers are designed to?
Move high volume and low pressure air.
What compressors require more horsepower per cfm?
Centrifugal Compressors.
When trying to control the centrifugal compressor output what is the most effective way?
Speed variation, however many compressors lose efficiency when the speed is reduced too much.
What can change the amount of water content in pressurized air?
Humidity and Temperature.
What cooling is economical for what type of compressors?
Medium-Sized single stage compressors operating more than 8 hours a day and for larger compressors or any that operate more than 10 hours a day.
What do air receivers allow for?
The capability to balance off available compressor capacity against much larger peak air-flow demands that occur.
Centrifugal separators also known as internal separators work in what way?
The inertia of a heavy moving particle to aid in the separation, the heavier a particle is and the faster it is moving, the more it tends to travel in a straight line, therefore when it is forced into a circular path it has a natural tendency to move outward.
If it stops 100% of a given particle size, this size is referred to as?
Absolute Rating
Wetted air filters have a slightly higher initial cost than dry filers but…
They can be cleaned many times.
Fire lubricators are especially effective in what systems?
Complicated piping systems and intermittent equipment operation.
To avoid turbulence in inner walls for an air piping system what should you do?
The inner walls should be smooth and piping should not change direction more than necessary, also the number of fittings should be kept to a minimum.
The slope when installing air lines should be what?
1 inch for every 10 feet as well as in a downward direction in the direction of air flow.
-
TPC 30944
-
Eaton Ch. 1020
-
Eaton Ch. 1110
-
Eaton Ch. 1510
-
Eaton Ch. 1710
-
PHEP Ch. 23 Transformers35
-
PHEP Ch. 30 Switches and Switching Equipment26
-
Circuit Breakers5
-
General Electric (Pg.1-7)9
-
Westinghouse Ch. 1 & 212
-
PHEP Ch. 27 Protective Equipment15
-
PHEP Ch. 8 Piping System26
-
PHEP Ch. 12 Intakes, Conduits, Surge Chambers31
