Introduce About Oil-free Screw Air Compressor

Sep 14, 2024

What is oil-free screw air compressor?

The oil free screw air compressor compresses the rotor air through a two-stage screw, and removes the matrix in the compressed air through a water-gas separator. At the same time, because there is no oil injection cooling, the pre-cooler, intercooler, and after-cooler are generally configured for compression in the shaft of the rotor through an excellent shaft seal to prevent condensation from leaking into the compressed air to achieve true oil-free.

The characteristics of oil-free screw air compressor?

1. Because of the high viscosity of the lubricating oil, the current oil removal equipment can not be completely removed, so that the oil-free gas compressed by the oil-free industiral screw air compressor is irreplaceable.

2. At present, water removal equipment such as refrigerated dryers, non-thermal regeneration dryers, and micro-thermal regeneration dryers lose water removal function due to oil in compressed air; The clean oil-free gas compressed by the all-oil-free compressor fully protects the water removal equipment and reduces the additional capital occupation caused by the maintenance of the water removal equipment.

3. The use of all-oil-free air compressor to provide compressed gas to the outside, which will not greatly reduce the motor load due to the pressure loss caused by the oil removal equipment, and achieve energy saving effect; At present, the good quality three-stage oil separator will produce 1 to 1.2 kilograms of pressure loss during use, and a 7.5KW air compressor will pay 600W more power loss for every 1 kilogram of pressure increase, and 6 degrees of electricity will be paid for every working day (10 hours as an example), which will be a long-term intangible expense.

4. The use of oil air compressor greatly wastes lubricating oil, taking a 7.5KW high-quality oil air compressor as an example, the minimum consumption of 5kg of lubricating oil per month will pay more than 60kg of lubricating oil use cost over the next year, at the same time, in order to remove the oil in the compressed gas, to use an efficient oil filter, it is necessary to replace the filter core several times, which is also a great cost.

How does oil-free compressor work?

Rotary screw compressors are positive displacement compressors. The compression principle of oil-free rotary screw compressors is similar to that of oil-injection compressors, but there is no need to inject oil into the compression chamber. There are two different types – dry and waterlogged.

In a dry oil-free rotary screw compressor, the meshing rotors do not touch, and their relative positions are maintained by lubricating timing gears outside the compressor. In the water injection type, a similar timing gear structure is used, but water is injected in the compression chamber to act as a seal to the internal gap and remove the heat of compression.

Oil-free rotary screw compressors use oil to lubricate bearings and gears, which are isolated from the compression chamber. Therefore, the lubricating oil will not pollute the compressed air. The cooling system of dry oil-free rotary screw compressors usually consists of an air cooler and an oil cooler after each stage. Water jet oil-free rotary screw compressors use water to eliminate compression heat. The injected water is then removed from the discharged compressed air by a conventional water separation device.