INTER-COOLER IN COMPRESSOR

Q. WHAT IS THE NECESSITY OF INTER-COOLER IN AIR COMPRESSOR?
ANS:
 To avoid excessive temperature rise associated with higher compression ratios, and to

1. Approach ISOTHERMAL COMPRESSION 

Result: Isothermal compression reduces compressor work hence saving in power.

2. Saving in power.

Reason As explained in point no. 1.

3. Volumetric efficiency is increased.

Reason: volumetric efficiency is the ratio of the amount of gas entering the compressor (suction) versus the amount of gas leaving the compressor (discharge).

since due to inter -cooling the volume of air is reduced due to reduction of temperature and hence the amount of air inlet after intercooler to next stage has increased which will also increase the amount of air discharge. Hence volumetric efficiency will increase.

4. Reduced the volume of air delivered and also reduced the compressor size.

Reason: When we compare a compressor having inter-cooler to the one having no inter-cooler , the compressor without intercooler will be bigger in size for the same output then the compressor with inter-cooler.

5. It reduces the air temperature.

Reason: Since it is a heat exchange process.

6. Due to less temperature suction & delivery valves remain cleaner without being fouled with carbonized oil.

Reason: High temperature operation requires frequent maintenance.

7. It allows good lubrication of the compressor piston.

Reason: As we know for proper lubrication(cylinder & piston ring) to establish there must be optimum temperature if temperature is high due to any reason, the lubrication will break which result in metal-to-metal contact and increases the wear.

8. Moisture separation is easier through inter cooler drains.

Reason: As we are using atmospheric air to compress it and by default atmospheric air contains moisture which is harmful in many ways so every intercooler is fitted with drain valve. Moisture will get condensed when it come in contact with cooling media and that will be drained by drain valve fitted in inter-cooler.

9. It also enables to deal with a greater weight of air for the same energy expended.

Reason: Due to reduction in volume the mass and the weight of air will increase for the next stage of compression.