Air Compressor
Compressors Types -Rotating, Reciprocating, Centrifugal & Screw
Reciprocating Air Compressor
Electric Motor gives Rotating Motion to Crank Shaft.
Other Constructions are similar to that of an IC engine
Connecting Rod converts Rotating Motion of Crank Shaft to Reciprocating Motion of Piston
When Piston Moves down – Air (at atm pr) is sucked into the Cylinder through Inlet Valve
When Piston Moves up – Air is Compressed.
Compressed Air leaves the Cylinder through Outlet Valve
If High Pressure is required – No. of Stages / Cylinders should be Increased (Multi Stage)
Temperature of Air Increases when it is Compressed
Air is Cooled after each Stage (before entering the next stage) using an Inter Cooler
Air is Cooled after the Compressor Outlet (before entering the Air Bottle) using an After Cooler
Safety equipments fitted in an Air Compressor
Relief Valve
Bursting Disc
Fusible Plug
Lub Oil Low Pr Alarm and Trip
Motor Overload Trip
Storage of Compressed Air
Compressed Air is stored in Air Bottles
Equipments / Safety Equipments fitted in an Air Bottle
(i) Relief Valve – It is fitted to prevent the Air Pressure (inside
the Air Bottle) from exceeding the Max Working Pr
It is fitted on top of Air Bottle
(ii) Fusible Plug – If the Relief Valve can be isolated from the Air Bottle then a Fusible Plug is fitted
It is fitted on top of the Air Bottle
In the event of fire it discharges the contents to outside of the ER
(iii) Drain Cocks – It is used to drain the Air Bottles (frequently) to prevent accumulation of oil /water
They are fitted at the bottom of Air Bottles
(iv) Pressure Gauge – It is fitted to indicate the pressure of the of the Air inside the Air Bottle
It is fitted at the viewing height