Industry News

Non action of the main bearing seal after the action of the bearing seal

Update:Mar 2018,07

This phenomenon is often referred to as the main safety […]

This phenomenon is often referred to as the main safety gate. Refuse the main security door wind generator in operation against a very large, a major equipment problems, seriously affect the safe operation of equipment, when the medium pressure operation of pressure vessels and piping in exceeds the rated value, the main security gate does not move, so that the equipment can easily run over pressure equipment damage and major accident.
• through practice, the main safety door refusal is mainly related to the following three factors:
• 1  Is the blocking phenomenon of the moving parts of the seal. This may be due to improper assembly, contamination of dirt or impurities, corrosion of parts, poor surface finish of piston chamber, surface damage, and hard spot of groove mark. In this way, the friction between the moving parts and the fixed parts is increased, and the main safety door is easily rejected in the condition that other conditions are constant.
This defect is: - eliminate maintenance of the piston, the piston rings and the piston chamber of the piston chamber rust treatment, groove defects such as grinding, assembly before the piston chamber wall evenly coated with lead, and in strict accordance with the order of seal assembly. In the wind turbine hydraulic pressure test, flushing of the pulse tube, and then the main security gate and impulse bearing seal connection, after overhaul furnace again when the bearing seal test run mound all normal.
• 2  Is the large leakage of the piston chamber in the main safety door. When the air leakage of the piston chamber is large, the force acting on the piston is small, and the main safety door is refused under the condition of other conditions. The main reason for the large leakage volume of the piston chamber is related to the tightness of the sealing body and the requirement that the piston ring does not meet the size requirements, or that the piston ring wear is too large to meet the sealing requirements.
The way to eliminate this defect is to deal with the piston interior surface, replace the qualified piston and piston ring, and close the throttle valve opening in the throttle valve impulse safety device system. Increasing the intake volume of the main safety door piston chamber, if conditions permit, we can increase the intake volume into the main safety door piston chamber by increasing the stroke of the impulse bearing seal, so as to promote the main bearing seal operation.
3  Is the mismatch between the main bearing seal and the impulse bearing seal, and the steam flow of the bearing seal is too small. The nominal diameter of the bearing seal is too small, which causes the steam volume flowing into the piston chamber of the main bearing seal is insufficient, and the force acting on the piston's downward movement is not enough, resulting in the main bearing seal valve core is not moving.
This defect is: - eliminate bearing seals disintegrated, the guide sleeve and spool part of the gap expanding, in order to increase the common flow area, again a successful test run mound. Therefore, the bearing seal is mismatched with the main bearing seal, and the smaller nominal diameter will also cause the main bearing seal to refuse to move.