Water turbine air brake braking air pressure control self-checking device and method

Abstract

The invention discloses water turbine air brake braking air pressure control self-checking device and a method. The device comprises an air brake, an air pressure mechanism and a contact mechanism, the air pressure mechanism is arranged in a working piston of the air brake, the contact mechanism is arranged outside the working piston, and pressure air enters a cylinder body to drive a balance weight piston of the air pressure mechanism to move upwards; and a strong magnet and a moving contact of the contact mechanism are magnetically attracted, the moving contact and a static contact are in contact to be closed or disconnected and separated to detect whether the air brake leaks air or not, and a specific node of the air brake for braking a water turbine rotor is controlled. According to the device, the problems of failure caused by uneven stress and air leakage of the air brake in the shutdown braking process of an original hydraulic turbine set and incapability of discriminating the failed air brake in the braking process are solved, and the device has the advantages of simple structure, air leakage detection of the air brake before braking, balanced braking stress, discrimination of the air leakage air brake, avoidance of failure of the air brake, and simplicity and convenience in operation.

Description

technical field [0001] The invention belongs to the technical field of stopping braking of hydraulic turbine units, and relates to a self-inspection device and method for hydraulic turbine air brake braking air pressure control. Background technique [0002] During the shutdown process of the hydro-generator, the water guide vanes are fully closed, and the speed of the water turbine decreases. Because the oil film of the bearing will be destroyed at low speed of the water turbine, the bearing friction will be too large, and the temperature will rise and burn. Shorten, reduce the travel time of the unit below the rated speed, and stop quickly to achieve the purpose of protecting the hydroelectric generator set. [0003] The main functions of the air brake are: to prevent the unit from running at low speed for a long time during the shutdown process, and to brake quickly; during the installation or maintenance of the unit, to jack up the rotor; to prevent the unit from rotatin...

AI Technical Summary

Problems solved by technology

[0005] During the braking process, the number of air brakes is large, the pipeline is long, and the time difference between the air pressure reaching each air brake cylinder is relatively large, resulting in that the brake rings of multiple air brakes are not in contact with the lower side of the rotor at the same time, resulting in The dynamic force is uneven; secondly, the air brakes are operated frequently or for too long, and their seals are damaged or aging, resulting in air leakage, causing some air brakes to fail, and some of the failed air brakes cannot be identified during the braking process

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