Authors

Background for the use of gas-static bearings in screw compressors

UDC 621.51

Background for the use of gas-static bearings in screw compressors

Il'ina Tamara E., Pronin V.A.

Abstract
The aim of this work is to evaluate the possibility of gas-static bearings application for dry screw compressor. The paper briefly describes the advantages of screw compressors. The paper presents downsides of oil-injected screw compressors. It is shown that for the effective use of dry screw compressor is necessary to use the new constructive and technological solutions. To fully exclude the oil system from the composition of dry screw compressor is necessary to modernize bearing units – slide bearings. For this aim in composition of dry screw compressor gas-static bearings are recommended to use. The calculation of forces in the bearings of the screw compressor has shown that for the use of gas-static bearings we have to use special unloading unit. In addition, due to the fractional gas feed in the discharge area of the dry screw compressor the pressure fluctuations occur. Solution of problem of gas-static bearings stability to external vibrations is to use self-aligning pads with combined automatic control system (ACS) based on fluidics automation. The paper presents the project of four-channel automatic control system for shaft position with feedback on pressure in the gap that can be used in the construction of gas-static bearings.

Keywords: gas-static bearing, screw compressor of dry compression, unloading devices, basic reactions, system of automatic control (SAC), jet elements

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