The sealing surface of the gate valve is the core part of the valve. There are four ways of leakage: leakage of the sealing surface, leakage of sealing ring joint, leakage of sealing piece falling and sealing cover insert foreign body.
1. The sealing surface of the metal seal gate valve is uneven and does not form a sealing line.
2. The connection between the stem and the sealing piece is suspended, incorrect, or worn.
3. The valve stem twists or improper equipment make the sealing parts tilt.
4. Unscientific material selection of sealing surface or valve selection is not suitable for working conditions, resulting in corrosion, erosion and wear of sealing surface.
5. The surfacing welding and heat treatment are not operated according to the regulations, and wear occurs due to hard working, corrosion caused by burning loss of alloying elements, and leakage of sealing surface of metal sealing gate valve due to cracks caused by excessive internal stress.
6. The metal seal gate valve has been fully closed in place, but continues to apply excessive sealing force, including improper long lever operation, and the sealing surface is extruded and deformed.
7. The sealing surface wear is too large and the sealing surface cannot be well sealed.