How to Select and Replace the Seal Ring of Soft Sealed Gate Valve
Publisher：Botou Valve
Soft sealing gate valves are widely used. The opening and closing parts of soft sealing gate valves, industrial valves and soft sealing gate valves are gates. The movement direction of the gate is perpendicular to the direction of fluid. The gate valves can only be fully opened and closed, and can not be adjusted and throttled. The gate has two sealing surfaces. The two sealing surfaces of the most commonly used mode gate valves form wedges. The wedge angle varies with the valve parameters, usually 50. When the medium temperature is not high, it is 2 degrees 52''''''.
1. Selection principles of sealing gaskets for soft sealing gate valves:
1. Soft-sealed gate valves can be selected by experience and replaced at an inappropriate time when the requirements are not high.
2. For strictly demanding occasions, such as explosive, highly toxic and combustible gases, corrosive liquid equipment, reaction tanks and pipeline systems, the selection should be based on working pressure, working temperature, corrosiveness of sealing medium and the form of combined sealing surface.
3. In normal temperature and low pressure, choose non-metallic soft gaskets; in medium pressure and high temperature, choose metal and non-metal combination gaskets or metal gaskets; in temperature and pressure fluctuations, choose elastic or self-tightening gaskets; in low temperature, corrosive media or vacuum conditions, should consider gaskets with special performance.
2. Principle of replacing sealing ring of soft sealing gate valve under pressure:
1. In the case of medium flange gasket, pressure relief is generally required before valve cover can be replaced (as for sealing gasket, it can be repaired online with pressure, the specific method and process can be consulted in the valve online maintenance manual).
2. If it is a stem seal ring, it is necessary to open the valve to the full open position first, so that the reverse seal can ensure that the medium will not leak, and then replace the stem seal ring, the pressure of the soft seal gate valve is generally 1.6 MPa.
3. If the seat is soft-sealed, the valve must be removed before it can be replaced.
