[Mechanical Equipment Technology Edition] Daily Question 20180106: Common Faults in Refrigeration Systems (5)
Thread Content
This post was last edited by YORK Industrial Refrigeration on 2018-1-9 at 08:51. Starting from now, in order to enhance communication among members, a \"Question of the Day\" campaign has been launched on the Mechanical Equipment Technology forum. We hope everyone will participate actively to progress and improve together! ! ! Rewards: 3 wealth points for active participation, 10-15 wealth points for correct answers. This question is valid for two days; no score will be assigned after that period. When a screw refrigeration compressor is operating normally, which is the component inside it that is subject to the greatest stress? What force is he bearing? Bearings bear the axial and radial forces exerted on them by the screw ============================== Premium promotion: Moving equipment——Summary of work done by equipment managers in 2017 https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1881872 Moving equipment——Maintenance procedures for York screw compressors https://bbs.hcbbs.com/thread-1806833-1-1.html Moving equipment——Upgrading of York Quontum control centers https://bbs.hcbbs.com/thread-1804837-1-1.html Moving equipment——Major repairs of GEA Grasox screw compressors https://bbs.hcbbs.com/thread-1800467-1-1.html Moving equipment——Disassembly and maintenance of British HOWDEN screw compressors https://bbs.hcbbs.com/thread-1832529-1-1.html Moving equipment——Disassembly and maintenance of Japanese Maekawa MYCOM screw compressors https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=
The rotor is under the greatest stress. It mainly bears axial and radial forces of the gas.
When a screw refrigeration compressor is operating normally, which is the component inside it that is subjected to the greatest stress? What force is he bearing? Bearings, axial and radial.
Single-screw compressor: The radial and axial gas forces acting on the screw can be automatically balanced; the star wheel teeth are subjected to gas forces, which requires them to have sufficient strength and stiffness. Double-screw compressors: The screw rotors are subject to significant radial and axial gas forces, requiring the screws to have sufficient strength and stiffness.
The operation of a screw compressor relies on the meshing motion of an male rotor and a female rotor, and it takes place within the space defined by the inner wall of the casing that surrounds these two rotors. As the rotor rotates, the V-shaped inter-tooth volume formed by the rotor’s teeth, tooth grooves, and the inner wall of the casing is known as the elementary volume. The size of this volume changes periodically, and it also moves along the axis of the rotor from the suction side to the discharge side, drawing in the refrigerant gas, compressing it to a certain pressure, and then discharging it. Single-screw compressor: The radial and axial gas forces acting on the screw can be automatically balanced; the star wheel teeth are subjected to gas forces, which requires them to have sufficient strength and stiffness. Double-screw compressors: The screw rotors are subject to significant radial and axial gas forces, requiring the screws to have sufficient strength and stiffness. Sliding bearings, thrust bearings.
The rotor is subjected to the greatest stress; its surface is under the pressure of the medium, while its two end faces are exposed to suction pressure and exhaust pressure (this force is complex due to the differences in pressure between the teeth), as well as the force exerted by the oil.