Five Ways to Learn How to Deal with the Problem of Valve Leakage
Leakage is the often encountered problem for valves and sealing is one of the difficulties for special ball valve manufacturing, so how to remedy this problem?
1. Spray welding technology. At present, many valve manufacturers adopts imported spray welding technology in order to improve the spray welding processing.
2. The run-up to spray welding process. Good binding force is needed between the coating material and substrate material. The pretreatment of spraying is particularly important. The roundness of sphere is directly related to the sealing performance of valve. Usually, for the sphere after spraying, it will experience the CNC spherical grinding machining, and then through precision grinding by home-made grinding equipment to ensure the ball roundness within a certain range combining the coordinate measuring machine (CMM), in this way, the metal hard seal ball valve can pass the gas seal test.
3. Machining precision. For hard seal ball valve, even with a little deviation between parts, sealing performance will be affected.
4. Sealing performance between the seat and body. Generally, using graphite fillings can reach the effect of reliable sealing, by the way, it is a light and nimble operation. The choice of graphite sealing ring and its sealing performance determine the sealing performance between seat and body.
5. Sealing materials. Sealing materials such as gaskets, fillers also are very important. The level of leakage should meet the requirements of API 6D. In addition, there is a kind of structure with bellows sealing between the seat and body, but this structure also has the problem of medium deposition.
1. Spray welding technology. At present, many valve manufacturers adopts imported spray welding technology in order to improve the spray welding processing.
2. The run-up to spray welding process. Good binding force is needed between the coating material and substrate material. The pretreatment of spraying is particularly important. The roundness of sphere is directly related to the sealing performance of valve. Usually, for the sphere after spraying, it will experience the CNC spherical grinding machining, and then through precision grinding by home-made grinding equipment to ensure the ball roundness within a certain range combining the coordinate measuring machine (CMM), in this way, the metal hard seal ball valve can pass the gas seal test.
3. Machining precision. For hard seal ball valve, even with a little deviation between parts, sealing performance will be affected.
4. Sealing performance between the seat and body. Generally, using graphite fillings can reach the effect of reliable sealing, by the way, it is a light and nimble operation. The choice of graphite sealing ring and its sealing performance determine the sealing performance between seat and body.
5. Sealing materials. Sealing materials such as gaskets, fillers also are very important. The level of leakage should meet the requirements of API 6D. In addition, there is a kind of structure with bellows sealing between the seat and body, but this structure also has the problem of medium deposition.
