TYPES OF ROTARY SCREW AIR COMPRESSORS
There are two types of rotary screw air compressors widely used by industries, they are oil-lubricated and oil-free rotary screw air compressors . In the oil-free screw air compressors, the air is compressed through the action of the screws. The oil-free screw compressors are preferred in the industries that cannot tolerate presence of oil in their operations.
On the other hand, in the oil-lubricated air compressors , oil is injected into the compression chamber to aid lubrication. These type of screw air compressors are used in applications that can tolerate slight levels of oil such as drilling, mining , metallurgy, etc.
WHAT IS A ROTARY SCREW COMPRESSOR AND ITS BENEFITS?
Rotary screw air compressors work on the principle of positive displacement. The rotary screw compressors can perform a high-speed operation over various operating pressures and flow rates at high efficiencies. The rotary screw air compressors have no valves or other mechanical forces that may cause unbalance. This allows the compressor to operate at high speeds while combining a large flow rate with small exterior dimensions. These compressors are an advantage because they can continuously supply compressed air with minimum fluctuation in the delivery pressure and generate less heat than standard air compressors, resulting in energy efficiency. Other benefits of rotary screw air compressors include:
Rotary screw air compressors are safe and convenient since they provide continuous air delivery for the required application with minimal chances of an accident.
Rotary screw air compressors can perform at extreme temperatures and any form of energy.
Rotary screw air compressors demand low maintenance costs.
Long-lasting as they have little to no capacity reduction.
The rotary screw air compressors are designed to operate tools that generate more power than typical equipment.
Generate low noise output.
Minimum oil-carryovers that are as low as 3 ppm in the oil lubricated machine
ELGI’S ROTARY SCREW AIR COMPRESSOR PROFILE
ELGi’s rotary screw air compressor profile consists of several segments, each different shape.
Large positive displacement increases the air’s pressure by reducing the air volume.
A strong female rotor helps tap more air and continuously reduces the space.
A short sealing line maintains a seal over the entire contact length, eliminating the need for a sealing strip.
Better clearance distribution.
WORKING PRINCIPLE OF THE ROTARY SCREW AIR COMPRESSOR?
The rotary screw air compressor uses a positive-displacement mechanism. The screw consists of two rotors similar to a helix, each of a different shape and number of grooves/teeth. The atmospheric air sucked into the screw gets compressed as it progresses along with the rotors. The male and female rotor elements trap and release the air when required.
In an oil-lubricated rotary screw air compressor, the male rotor is driven by the motor or engine, and the female rotor is driven by the male rotor or by the thin film of oil between them.
In an oil free rotary screw type air compressor a set of gears control the timing between the male and female rotor. There is no oil to seal the chamber.
The basic principle of a rotary-type compressor is that the male and the female rotors spin in opposite directions. The prime mover turns the rotor of the airend in a rotary screw air compressor. This develops a vacuum which results in surrounding air being driven into the airends through the air filter. As the rotors turn progressively, the air gets trapped in the spaces between the two screws (rotors).
Air is taken from the atmosphere into the rotary screw compressor through the air intake system. First, it passes through a filter that helps in removing suspended particles from it. Next, the filtered air goes in the airend, which is the heart of the rotary screw compressor. Here the air is trapped within the spaces between the two rotors with lobes that mesh with each other. As the rotors turn, they progressively compress the trapped pockets of the air, discharging the compressed air at the outlet of the airend.
ELGi’s EN & EG series are good examples of best-in-class rotary screw electric air compressor technology, an ideal footprint for industrial applications.
