screw compressor

A screw compressor is a type of compressor which uses a positive displacement rotary mechanism. These compressors are widely used in industrial applications and replace, for example, conventional reciprocating compressors that require more significant amounts of compressed gas. It is used in large cooling circuits as a cooler or in compressed air systems to operate pneumatic tools such as rock drills and impact wrenches. When the rotor size is small, the inherent rotor leakage becomes more significant, and this type of mechanism is not suitable for smaller compressors compared to reciprocating compressors.

In contrast to root blowers, the two rotors of the modern screw compressor contain various contours. The male rotor has convex wings that interlock with the concave hollow of the female rotor. In general, male rotor contain less number of blades than female rotors, so they spin faster.  

Working of Screw Compressor

Screw compressors use two very close-meshed spiral screws (so-called rotors) to compress the gas. On dry screw compressors, the timing gear keeps the male and female rotors precisely aligned with no contact or rapid wear. In oil-immersed screw compressors, the lubricant forms a bridge between the rotors, creates a hydraulic seal, and transfers mechanical energy between the rotors so that the other rotor can ultimately drive one rotor. The gas enters the suction side and flows through the thread when the screw turns. The mesh rotor pushes the gas into the compressor and expels the gas at the end of the screw.

The working area is the volume between the female and male rotors. It is large at the inlet end and tapers along with the rotor to the outlet port. This change in volume is a compression. The intake air is drawn into the large space between the male and female tunics at the end of the rotor. At the inlet end, the male wing is much smaller than the female wing, but its relative size is inversely proportional to the length of the two rotors (until it touches the outlet port) (larger male wing, larger female wing, small). The separation space between the blades between the individual rotors is much smaller. This reduction in volume compresses the charge before it enters the exhaust manifold. 

Components of Screw Compressor

The major components of the screw compressor are given below: 

1) Rotor

The screw compressor consists of a pair of rotors located in a cylindrical chamber. The compression procedure occurs inside this chamber. Depending on the structure, the rotor can be male or female. Male rotors have blades, and female rotors have flutes or flutes. Male rotors typically have four rotors, and female rotors have six rotors.

The slaughter of males forms the head of power. On the other hand, the female rotor is a driven rotor.

The rotor has a spiral groove along its length. Seen from the side, it looks like a screw. This unique aspect gives them the name screw compressors.

2) Cylinder

The compression progression occurs within this cylinder. The rotor and other components used for compression are mounted on the cylinder. Like axial compressors, screw compressors can be combined in several stages by combining several cylinders. Each cylinder has its own rotor assembly.

The compression cylinder also supports filters and oil lubrication systems.

3) Filter

Compressors remove air from the atmosphere, which can contain a variety of contaminants. The presence of these particles will reduce the overall efficiency of the system. The accumulation of these substances on rotors and other moving parts can cause the machine to stop or fail. To avoid such extreme situations, use an air filter to clean the intake air. The air filter ensures that the compressor machine works easily and efficiently.

With oil-injected air compressors, the rotor and other compressors are in an oil bath. Facilitates proper lubrication and cooling. These types of compressors use an oil filter to remove oil from the compressed air.

4) Valve

The valve uses to draw in the fresh air and expel compressed air from the machine. The suction valve on top of the compressor draws air from or around the tank. With screw compressors, the process is continuous, so the device always draws in a certain amount of air.

In addition to the suction valve, there is also an outlet valve. Its function is to expel the pressurized fluid from the compression chamber.

5) storage tank

This tank locates inside the compressor and uses to temporarily store the pressurized fluid until it is added to the supply.

Applications

Screw compressors are widely used to provide compressed air for large industrial applications. The screw compressor is ideal for applications with continuous air demand, such as food packaging lines and automated manufacturing systems, but sufficient intermittent demand and some storage also ensure adequate continuous loading. In adding to stationary equipment, these compressors mount on trailers and driven by small diesel engines. 

These portable compression systems are often referred to as construction compressors. Construction compressors use to supply compressed air to rock drills, riveting tools, air pumps, sandblasting systems, and industrial painting systems. They are common on construction sites and in road service personnel around the world.

By Anurag Rathod

Anurag Rathod is an Editor of Appclonescript.com, who is passionate for app-based startup solutions and on-demand business ideas. He believes in spreading tech trends. He is an avid reader and loves thinking out of the box to promote new technologies.