Air Compressors – Recommended Parts to Keep in Stock

April 25, 2015

Air Compressor is essentially a machine that converts electric power or gas power in case of engine operated compressors, in to pressurized air. This compressed air at high pressures has a lot of potential energy that can be used for several important purposes like painting, cleaning, driving air tools, medical equipment and so on.

It is vital to have uninterrupted supply of air when needed. As with any other rotating equipment, air compressor will also need periodic maintenance and replacement of wear parts. In addition, there could be premature failure due to inappropriate operation, malfunction or accidents.

As an air compressor owner, you need to know what the essential parts are, that you need to keep in stock so that you can ensure trouble free operation and uninterrupted supply on compressed air. This article deals with identifying these essential parts.

Different types of air compressors

There are various types of air compressors in the market. But for the purpose of this article, we will focus mainly on two more commonly used  types: Reciprocating and Rotary Screw type air compressors.

Reciprocating Type Air Compressors

As it is evident from the name, this type of compressor has a reciprocating piston that steadily moves back and forth inside a compression chamber to produce compressed air. The reciprocating motion is produced from the rotational movement of a crank shaft which is connected to the piston through a piston rod. The crank shaft receives the rotational motion from an electric motor or a gas engine.

The major components on a reciprocating piston type compressor are mentioned next: cylinder head, suction valve, delivery valve, cylinder liner, cooling water jacket, compressor casing, crank case, crank shaft, connecting rod, piston, main bearings, bed plate, stage relief valves, intercoolers, after-coolers, intake filter lubrication oil strainer, etc. Some of the minor parts will include springs, pins, rings, O rings and gaskets.

While it is not practically possible for the owners to keep all these parts in stock for service purposes, here are some of the recommended parts to keep in stock.

  1. O Rings
  2. Gaskets
  3. Relief valves
  4. Oil Strainer
  5. Piston Rings
  6. Suction Valve
  7. Springs
  8. Pins
  9. Drive Belts

As the unit gets older you may consider keeping the following parts in stock as well.

  1. Cylinder Liner
  2. Piston Assembly
  3. Connecting Rods
  4. Main bearings

Rotary screw compressors

These types of air compressors make use of a rotary type positive displacement mechanism to compress the air. This rotary mechanism is coupled to an electric motor or a gas engine . Rotary screw compressors are generally used to replace reciprocating types where compressed air is needed in large volumes at high pressure such as large industrial applications or to operate high-power air tools.

The compression process of a rotary screw is a continuous sweeping motion; hence there is very low pulsation or surging of air flow, as compared to the reciprocating type of compressors. This enables the rotary screw compressors to run smoother, quieter and with lower vibration levels.

The recommended parts to keep in stock are mentioned below:

  • O rings and Gaskets
  • Relief valves
  • Inlet Air Filters
  • Oil Filter / Coolant Filter
  • Air/Oil Separator
  • Drive Belts
  • Automatic Belt Tensioning Device

System Components

The above are parts of the compressor itself. It is also recommended to keep system components such as pressure gauges, check valves, hoses and hose connectors in stock to ensure smooth operation of your system.

Before placing purchase orders of any spare parts, always refer to owner’s manual in order to make sure that the right parts are purchased.