平板闸阀的工作原理和产品结构特点
平板闸阀的工作原理:双重密封、自动泄压、免维护
1、阀门内部压力相当时（1），闸板处于闭合状态，阀座表面PTFE密封环形成初始密封，每次阀门开或关时，阀座圈能清洁闸板两侧
2、对阀门施加管理压力时（2），压力作用于闸板，迫使它贴近出口阀座上PTFE环，压缩它直到闸板停在钢制阀座上，这样，就形成了双重密封，首先是PTFE对金属密封，然后是金属对金属密封，阀座也被牢固地捡到凹槽，在这一点（3），O形圈阻止任何后部介质流。
3、阀体压力泄放后，形成进口密封，管道压力作用于进口阀座（4），使其移向闸板，这时形成PTFE对金属的密封，同时，O形圈（5）与阀座凹槽形成紧密的密封。
4、阀门自动泄放多余的压力，当阀体压力大于管道压力时，由于热膨胀，进口阀座推向凹槽，阀体内多余的压力在阀座与闸板之间泄放到管道中。
平板闸阀的产品结构特点Products design features
　　●阀体有铸造和焊接两种结构。
　　　Cast and weld two structures with the body

　　●阀座采用O形密封圈密封和施加预紧力的浮动阀座结构，使阀门进出口双向密封；并且该结构的启闭力矩仅为普通阀门的1/2，能达到轻松开、关阀门。
　　　The seal ring uses the floating seat ring structure with o-sear ring sealed and pre-tightening force applied to have inlet and outlet dual-way sealed;and the open-close moment with this structure is 1/2 that of the common valves only,able to lightly open and close valves.

　　●阀座采用密封面上镶嵌PTFE，具有PTFE对金属和金属对金属的双重密封，PTFE密封面同时清除闸板脏物的作用，
　　　The seat ring uses the sealing face inlaid with PTFE,so has dual seals of PTFE to metal and metal to metal, the PTFE sealingface also acts as removing the dirt on the wedge disc.

　　●金属对金属密封的阀门，阀体外部设有注油脂结构，油脂通过注脂器、阀座进入阀门密封面，使阀门达到零泄漏。
　　　For the valve with the metal to metal seal,there is grease injector outside of it,grease gets into the sealing face through the injector and the seat ring to have the valve up to null leak.

　　●带导流孔阀门的闸板，无论是全开或是全关始终与密封面吻合，密封面得到保护不受介质直接冲刷，从而延长使用寿命。
　　　The wedge disc of the valve with flow guide hole is always fitted with the sealing face whether in full open or full close status to have the sealing face protected without being directly eroded by the medium so as to extend the duration.

　　●阀门在全开时，通道平滑为直线，流阻系数极小，无压力损失，可通毛球清扫管线。
　　　When fully opened,the valve's channel is smooth and linear ,with an extremely small flow resisting coefficient and no pressure loss,and the pipeline can be cleaned with hair-ball through it.

　　●本阀采用带自密封能力的填料结构，无需经常调节，开、关极为轻便，且密封性可靠，填料函处设有辅助密封油脂注入结构，密封性能可靠，真正达到零泄漏；解决了通用阀门填料处zui容易外漏的蔽病。
　　　This valve uses the packing structure with the ability of self-seal,needs no constant adjustment,features very light open and close and a reliable seal An assisting sealing grease injection structure is set in the packing to have the sealing performance absoluy reliable and get a true null leak,settling the problem for the packing place of universal valves to be easiest leak outward.

       ●阀门关闭时能自动卸掉内腔高压（详见工作原理图），保证使用安全。
　　　Automatic removal of the high pressure in the internal cavity when the valve is about to close（see the working principle diagram）for the details） so as to ensure safety.

　　●全封闭结构，防护性能好，可适应全天候要求。
　　　Fully sealed structure leaves a good protective property,suitalbe for the requirement of 24-hour duty.

　　●升降杆阀门设有指示杆或观察窗以表示阀门的启闭情况，旋转杆阀门采用封闭齿轮转动启闭指示机构。
　　　An indication rod or viewing window is set Ascend and descend stemwith the valve to whow the open-close condition,Revolve stem with the valve Use a sealed gear-driving open-close indicating mechansim.

　　●直理式阀门外表面采用环氧煤沥青防腐处理，能与管线同寿命。
　　　The external surface of the directly built-in valve is corrosion resisting treated with epoxy coal bitumen and can be the same duration as the pipeline.