Globe Valves Glossary

    Valve sealing performance is the capacity of every parts of the sealing valve to prevent leakage of medium, it is the most important technology valve performance.
    Sealing places of valve has three parts: the contact points between two sealing surface of opening and closing pieces and valve seat; packing contacts between the department and the stem; the connection of valve body and valve cover.
    Among them, the leakage of the first case is called internal leakage, it is commonly referred as lax, it will affect the ability of the valve cut off media. For the truncated valve, the internal leakage is not allowed. The leakage of the two leakages behind called the leak, that media leaks from inside the valve to the valve outside. Leakage will result in material losses, environmental pollution, even will result in serious accidents. With the explosive, toxic or radioactive medium, leakage is not allowed, so the valve must have a reliable sealing performance.