Compressors – A Basic Introduction

A compressor is an important device that reduces the pressure of the air or gas by decreasing its volume. An oil compressor is such a device. The compressor uses the principles of dynamic pressure, which is similar to the law of conservation of energy. This means that as the compressor works more air is compressed and less gas is released. As a result, the compressor runs cooler. Compressors are used in various applications including automotive, chemical, and even the marine industry.

There are four different types of compressors namely axial compressors, radial compressors, reciprocating compressors, and centrifugal compressors. Among these, the axial compressors are the most commonly used. They can handle very high-pressure levels and are therefore the primary choice for industrial use. They are generally preferred over other types because they are not very noisy and because they produce less vibration. They also have better lubrication and are comparatively less expensive. The radial compressors are the next best choice.

A reciprocating compressor works by mounting a cylinder on top of another cylinder. This leads to a reciprocating motion. The larger the cylinder, the higher the number of cylinders that need to be moved to move the piston up or down. Thus, while providing high suction, the speed of reciprocating compressors is limited.

Rotary compressors are used to cool air and liquids. A rotary cooling fan is used to circulate the coolant. Cooling coils are mounted on the outside of the air compressor. Most rotary compressors have an automatic shut-off timer. This ensures that once the compressor has reached a certain temperature, it automatically shuts down. This is unlike other compressors that require manual stoppage.

Compressors can be either oil-lubricated or grease-free. Oil-lubricated compressors are used for heavy-duty industrial applications. In addition, they provide more efficient operation and longer service life than do grease-free compressors. In oil-lubricated compressors, an oil seal is formed in the piston stroke. Therefore, oil also increases the efficiency of the engine.

Lastly, there is the gas compressor, which mounts a closed-circuit gas cylinder. A separate burner unit heats the gaseous fuel and forces it through a larger intake manifold and into the air compressor’s intake cylinder. The air is pushed by a variable-speed blower located at the front of the cylinder. The pressure generated by the blower causes the gaseous fuel to be compressed and enters the combustion chamber. The compressed gas enters the combustible chamber where it is combined with oxygen to generate heat energy.

All four types of compressors have positive displacement compressors. Positive displacement compressors are designed to increase airflow and cooling as compared to their radial-type cousins. Positive displacement compressors are also commonly known as reciprocating piston-type compressors. They differ from compressors by having a crankshaft instead of a piston that creates a counter-rotating force.

There are additional compressors that function in a similar fashion as a refrigerant gas compressor, but these are not as common. Most home and small-scale industries use small-scale compressors instead of refrigerant-based compressors because refrigerants pose a safety risk when used alone. A refrigerant compressor mixes a liquid refrigerant with a powdered fuel or coolant gas to be cooled down prior to use. Some industrial compressors also feature an air conditioning unit that circulates chilled gas through a condenser.

A compressor can also be divided into hot and cold water compressors. The hot water compressor is used for heating water, while the cold water compressor is used for refrigeration. Some compressors function as both a compressor and an evaporator; others use a combination of both functions.

A two-stage reciprocating compressor is one of the most efficient compressor designs. It utilizes the principle of centrifugal force to increase air cooling. Two stages mean better efficiency and increased cooling, which results in lower utility costs. Two-stage compressors use refrigerants to increase the pressure of the gas flow. Centrifugal forces on the pulsed-liquid coolant result in a more powerful air compressor that is able to use more refrigerants than a radial-type compressor.

A rotary vane compressor, as its name implies, is a compressor that uses a rotary vane to increase cooling pressure. Rotary vane compressors utilize a fan-wheel attached to a rotor to increase cooling. A rotor attached to the fan wheel spins the vane, which causes the refrigerant to be drawn into the inlet of the compressor cylinder. Rotary vane compressors require relatively high pressure, so they usually are not as effective in smaller applications.