SCREW ELEMENT REBEARING SERVICE

The screw element is the most important part of any screw-type compressor. It’s that part of the machine, where the actual compression takes place. It is the heart of the rotary screw air compressor. Often, the compressor screw element is also called air-end. They are constant flow (volume) with variable pressure compressors. Which mean that at a given speed (rpm), they always supply the same amount of air (in liters per second for example), but can do so at different pressures.

We deal all makes and models of screw element (airend) reconditioning / rebearing services in chennai, like Atlas copco, Elgi, Kaeser, Ingersollrand, etc,.

Since it’s a continuous process (as opposed to reciprocating piston compressors) they supply a steady, non-pulsating air flow, with minimum vibrations and maintenance. It will give maximum life time. They can operate 24/7, 365 days a year. The normal lifespan of a screw element is about 40.000 running hours, before a complete overhaul is necessary. (Subject to Proper maintenance of oil level. wear & tear of Bearings, Gear teeth, Shaft and Sleeve)

Screw ELement containing two rotors (male rotor on the bottom, female rotor on the top) and the housing. The rotors have different kinds of bearings on both sides so they run smoothly for years without any maintenance. There are usually two pairs of bearings on both sides; bearings for radial loads (loads because of the turning of the rotors) and axial bearings.

The screw pushes to one side (the high pressure side) the rotors want to move to the opposite direction. The axial bearings take on this load and that the male rotor has an axle that sticks out with a gear on it. This is the driving gear. Sometimes it’s a pulley. The two rotors are also connected to each other by gears, these are the synchronization gears.
There is a sealing between the oil and the compressed air compartments, to prevent any oil from contaminating the compressed air.

Inside the compressor elements are two screws (called ‘rotors’) that turn in opposite direction. The rotary screw compressor is a ‘positive displacement’ compressor. The simply means, that the air is physically squeezed to gathers by an external force (like piston and scroll-compressors, which are also positive displacement compressors).

In the case of the rotary screw, the air gets trapped between the two rotors. The rotors have a special design for optimal efficiency and performance.
One rotor is called the ‘male’ rotor; the other one is called the ‘female’ rotor. Air gets sucked in on one side (cold-low pressure), gets trapped between the rotors, and discharged on the other side (hot-high pressure). This compression requires power, which is usually supplied by a big electro motor.