Compression fitting price inquiry quotation Liyuan fluid equipment manufacturing
Straight pipe valve card sleeve joint This is a common type The working temperature range of the medium is -20～+225℃. In order to prevent the medium from leaking out due to the movement of the valve stem, there is a packing chamber in the dead valve, which is filled with packing to play a sealing role. There are two commonly used fillers on the right: graphite asbestos filler and polytetrafluoroethylene filler. When graphite asbestos packing is used, proper grease should be injected frequently in the operation
to ensure that the seal lubricating grease dries up, which will cause leakage Or increase the frictional resistance of the valve stem movement, which makes the performance of the actuator worse. Polytetrafluoroethylene has good physical and chemical stability, and its sealing performance is better than graphite asbestos filler. It has gradually replaced graphite asbestos.
The assembly process and working principle of the ferrule joint:
When the ferrule joint is assembled , Tighten the nut, the nut pushes the rear ferrule, and the rear ferrule pushes the front ferrule joint body to move along the axis direction. Under the action of the screw force, the outer cone of the front ferrule 15° fits with the inner cone 20° of the joint. Tighten the nut, the rear ferrule presses against the tail of the front ferrule and pushes the front ferrule to move along the axial direction, forcing the outer cone of the front ferrule to produce umbrella-like deformation (the taper gradually changes from 15° to 20°), and the outer cone of the front ferrule is aligned with The inner cone surface of the joint body section is in full contact, forming a face seal.
The working principle of the ferrule joint is to insert the steel pipe into the ferrule, use the ferrule nut to lock it, against the ferrule, cut into the tube and seal . It does not need to be welded when it is connected to the steel pipe, which is beneficial to fire prevention, explosion prevention and high-altitude operations, and can eliminate the disadvantages caused by inadvertent welding.
Card The maintenance method of the sleeve joint is as follows:
1. Periodically check the tightness of the sleeve joint, and check through the drain nozzle. If there is internal leakage, follow the internal leakage treatment procedure Processing;
2. Inject a certain amount of fresh grease into the ferrule joint seat in a timely manner. The amount and frequency of injection depends on the frequency of the ferrule joint activity, generally When the ferrule joint is moved once, an appropriate amount of grease should be injected, and the amount of each injection is about 1/8 of the volume of the sealing system.
3. Carry out the maintenance and maintenance of the ferrule joint before the winter. The key point is to drain the water in the ferrule joint cavity and the actuator, which will affect the normal function;p>
4. For ferrule joints that rarely move, do less activity once a year and inject an appropriate amount of grease at the same time. This can prevent the ball and the ferrule joint seat from being glued and protect the ferrule Joint seat and ball.