固定球阀密封结构图

产品结构特点 Construction features

1、操作省力：球体由上下轴承支撑，减少摩擦，消除了由于进口压力推动球体与密封座形成的巨大密封负荷而造成过大的扭矩。

2、密封性能可靠(见图1)：PTFE弹性材料密封圈嵌于不锈钢阀座内，金属阀座尾端设有弹簧，保证密封圈足够的预紧力，阀门在使用过程中密封面磨损时，在弹簧作用下阀门继续保证良好密封性能。

3、防火结构(见图2)：为防止由于骤热或火灾的出现，使聚四氟乙烯密封圈烧毁，发生较大泄漏，而助长火势，在球体与阀座间设置防火密封环，在密封圈烧毁时，在弹簧力作用下，将阀座密封环迅速推向球体上，形成金属与金属密封，起到一定程度的密封效果。耐火试验符合API 6FA和API 607标准要求。

4、自动泄压功能(见图3)：当阀门中腔停滞的介质压力异常升高超过弹簧的预紧力时，阀座后退脱离球体，达到自动泄压的效果，卸压后阀座自动复位。

5、排泄管路：阀体上下均设置排泄孔，可检查阀座是否发生泄漏，在工作中，阀门处于全开或全关时，卸掉中腔压力，可直接更换填料；可以排放中腔滞留物，减少介质对阀门的污染。辅助密封设置系统 (客户需要请在订购时说明)

6、见图4：本阀门设计有辅助的阀座紧急密封系统，一旦密封受损或出现紧急情况而不能密封时，通过辅助密封系统向密封面注射相应的密封剂即可修复密封面，达到紧急密封。当输送的介质不洁或含有少量颗粒时，为保护密封面，确保达到可靠的密封，还可给这一装置注射相应的清洗剂或润滑剂对密封面进行清洗。

1. Operation saving force: the ball is supported by the upper and lower bearings,reducing friction and eliminating excessive torque due to imported pressure driving the large sealing load of the ball and sealing seat.

2, reliable sealing performance (see figure 1) : PTFE elastic material sealing ring is embedded in the stainless steel seat, metal seat end equipped with spring,guarantee seal enough pre-tightening force, valve sealing surface wear during operation, in the spring under the action of the valve to ensure good sealing performance.

3. Fire prevention structure (see figure 2) : to prevent because of heat or fire, make ptfe sealing ring burned, larger leakage occurs, and feeds the fire, set up fire prevention sealing ring between the sphere and valve seat, burned down in sealing ring, in under the action of spring force, the seat ring is rapidly to the sphere, form the metal to metal seal, have a certain degree of sealing effect. The fire resistance test complies with API 6FA and API 607 standard requirements.

4. Automatic pressure release features (see figure 3) : when the valve is the stagnation of midplane medium abnormal pressure rise more than spring pre-tightening force, the seat back out of the sphere to achieve the effect of pressure relief automatically, automatic reset after unloading seat.

5. And discharge pipe: body are set up and down the drain hole, can check whether the valve seat leakage, at work, when the valve is in full open or close,removing the midplane pressure, can directly replace the packing; It can discharge the middle lumen and reduce the pollution of the medium to the valve.Auxiliary seal setting system (customer needs to be specified in order)

6. As shown in figure 4: this valve design with auxiliary emergency seating system,once the seal is damaged or there's an emergency and cannot seal, seal face injection via the auxiliary seal system corresponding sealant can repair the sealing surface, emergency seal. When conveying medium impurity or contain a small amount of particles, to protect the sealing surface, ensuring reliable seal, but also injected a device with the corresponding detergent or lubricant was carried out on the sealing surface cleaning.