Chapter 75- Air Compression Flashcards
Compressed air tools
Are more more expensive than electrical tools
In a centrifugal compressor the kinetic energy is converted to potential energy in the
Both volute casing and diffuser
The compressor which would favour volume over pressure would be the
Centrifugal compressor
Positive displacement compressors
Can be single stage with three cylinders
Single stage reciprocating air compressors
Could have two cylinders
Sliding vane compressors
Are positive displacement compressors
A belt driven lubricator is very popular on a
Sliding vane unit
Where pistons move in a cylinder it is necessary for the lubricant to provide
Sealing
Higher gearing is commonly used on
Screw units
A type of air compressor which draws in a charge of air, traps it, reduces its volume and then discharges it, is called a
Positive displacement compressor
A type of compressor which imparts velocity to the air and then converts this velocity to pressure is the
A dynamic compressor
The determining factor as to which type of compressor to use is
The maximum operating pressure required
In a two stage air compressor the second stage is
Smaller than the first stage
Positive displacement air compressors include
Sliding vane, rotary screw, rotary lobe
Compressor unloaders
Could keep the suction valve open
To reduce air temperature between stages we would use
An inter cooler
An air compressor auxiliary which will decrease the power requirement is the
Intercooler
Intercoolers
Should have a safety valve
Must have a drain
Air receivers must have a
Safety valve
When an inter cooler is used it should be equipped with a
Thermometer
Safety valve
Pressure gauge
An after cooler which is equipped with a shut off valve between the after cooler and the receiver should be equipped with a
Safety valve
Name three common adsorbents
Bauxite
Activated alumina
Silica-gel
In order to regenerate the adsorbent when it becomes saturated with moisture it needs to be heated to about
150 degrees Celsius
An air receiver pressure vessel specifications must conform to
ASME section VIII
A start and stop compressor control should be set to operate at approximately ___________kpa pressure differential
100
A method to control the air compressor output which makes use of an internal combustion engine or steam turbine is the
Variable speed contro
The constant speed control method for an air compressor is usually driven by a
Electric motor
Air compressors may have a number of system protective devices. Another word for those devices is
Interlocks
Relative to a dry pipe fire system, an automatic air supply shall be connected so the proper pressure can be maintained in
National fire protection association code
In order to have economical and trouble free operation of an air compressor, the _____________ must be maintained
Correct working temperature
The cooling water for an air compressor should be turned on
Before starting the compressor
Compressed air machinery would most like be used in
Coal mines
