- Oil filters. This part is responsible in filtering the compressed oil. These are usually found in large compressors such as the screw compressor (oil-injected). Small compressors such as the reciprocating piston have no oil filter but the crankshaft is lubricated with the help of an oil bath. This is necessary to make sure contaminants within the oil is filtered such a dust, metal pieces and sand.
- Air filters. These filters are designed to make sure that no dust enters the compression system.
- Compressor valves. There are different valves within a compressor system and are used for various purposes.
- Inlet and outlet valves. These valves are present in industrial air compressor parts such as the reciprocating piston. The valves are responsible in controlling the piston compressor’s intake and exhaust. It ensures that no air is flowing back and its operation is dependent on the system’s pressure difference.
- Check valve. These are located in various points in the system and a minimum of two are present in the screw compressor. This can also be located between the air receiver and the reciprocating compressor to make sure that no air is flowing back to the system as soon as it stops.
- Unloader valve. There are two types of unloader valves, the small one found on reciprocating piston and the big one found on rotary screw. The small one is commonly called blow-down valve and is located in the compressor’s discharge line. The big one is installed in the rotary screw’s air intake and it unloads as soon as the limit pressure is reached.
- Pressure switch. This switch is responsible in making sure the compressor starts operation and stops operation when necessary.
- Compressor cooler. During compression, the system may generate a lot of heat and that is when a cooler or two is important. For smaller air compressors, the cooler used has a simple design and is located in the discharge pipe. For bigger machines, there are two coolers employed – the oil cooler and the after cooler. The oil cooler is responsible in cooling the heated oil before it is injected back to the system while the after cooler makes sure the air coming out of the machine is cool enough.
- Motors. Electro motors are used by small compressors whether stationary or portable. For bigger machines, diesel engines are used as a power source. For mean machines that are used on large plants, steam turbines are used since it is cheaper and safer compared to electricity.