Fixed Ball Valve

1.Block-up and excretion When the valve is in the closed state(Fig.7), the seat ring on the upstream and downstream sides cuts off the fluid and the accumulated matters in the middle cavity of the body can be excreted. The excreting device(Fig.8) features the following functions: ① Can check if the seat ring leaks or gets damaged beforehand; ② Reduce pollution to the valve due to the medium replacement; 2.Automatic pressure discharge When an abnormal pressure rise occurs with the medium stayed in the middle cavity of the valve due to rising temperature, the seat ring will come off from the ball and automatically discharge pressure(Fig.9) or the safety valve mounted on the body ensures the system safety. 3.Complete seal The unique sealing mode of the ball valve makes the fluid completely cut off. 4.Fire-fighting structure If the seat ring is made softened and burnt in case of a fire or an abnormal temperature rise ,the valve can be still reliably operated to prevent the fire from expanding and the seat ring's support can be contacted with the ball(Fig.11) To act as an instantaneous seal,conforming with API 607. 5.Electrostatic-proof structure During valve operation, the friction between the ball and the PTFE seat ring will produce electrostatic charges and they will be accumulated onto the ball. To prevent electrostatic spark from being produced, which may occur fire, (Fig.12) is mounted on the valve, which can guide the charges out through the electric path formed by both ball,stem, and body via the spring. 6.Emergent rescue of seal When the sealing parts of both seat ring(Fig.13) and stem(Fig.14) get damaged and thus leaks are caused, an instantaneous sealing action can be made available by injecting sealing grease through the grease injecting valve. 7.Structure of seat ring Two kinds: single-seal(Fig.15) and dual-seal(Fig.16).In general, those of an automatic pressure discharge function are single-seal while the dual-seal means the additional safety pressure discharge to the body.