The importance of an air dryer in the compressed air system
One of the most important industrial air compressor accessories is the air dryer because some of the end-user applications may require dry air. For example in the compressed air distribution system when pipes are exposed to extremely cold conditions, drying air to its dew points below ambient conditions would be necessary to prevent the buildup of ice. The best way to specify dryness is to cite a desired pressure dew point. There are three main types of air dryers with varying degrees of pressure dew point performance.
- Refrigerant dryers – are classified as non-cycling refrigerant, cycling refrigerant and variable speed refrigerant.
- Regenerative dryers – include heatless regenerative, exhaust purge regenerative and blower purge regenerative.
- Membrane dryers – make use of the semi-permeable membrane that separates water vapor from the air stream.
The air dryer is one of the industrial air compressor accessories that must not be overlooked by end users. Moisture is always present in atmospheric air which can condensate into liquid water in the compressed air system when air cools past its saturation point or the point where it can no longer hold more water vapor. This will occur at a specific temperature which is called dew point that will determine how much compressed air drying will be necessary. If there is moisture in the compressed air system, it can cause problems in the operation of pneumatic tools, solenoid valves and air motors in the manufacturing plant. Moisture causes rust and increased wear on the moving parts of production equipment since it can wash away lubricants. Operations that are dependent upon on proper functions of the pneumatic system can be jeopardized due to rust, scale and clogged orifices. Moisture can also freeze control lines during winter resulting in faulty operations of controls.
Why pneumatic tools need dry air
Pneumatic tools are designed to operate with clean dry air at a specific pressure. If there is moisture and dirt in the air, it can result into a sluggish operation that will require more frequent repairs and replacement of parts due to sticking, jamming and rusting of wearing parts. Oil which is used in the system can be washed away by moisture resulting into excessive wear. Any decrease in pressure required by a pneumatic tool due to plugged lines or parts will result into a reduction of its efficiency. Air dryers will ensure that there is clean dry air at a required pressure at the start of the operation. This will help in maintaining productivity and prolonging tool life.