平板閘閥按照使用場合和用途可分為帶導流孔平板閘閥、無導流孔平板閘閥、油田平板閘閥、燃氣平板閘閥及管線平板閘閥等。
平板閘閥的工作原理:雙重密封、自動泄壓、免維護
1、閥門內部壓力相當時，閘板處于閉合狀態，閥座表面PTFE密封環形成初始密封，每次閥門開或關時，閥座圈能清潔閘板兩側.
2、對閥門施加管理壓力時，壓力作用于閘板，迫使它貼近出口閥座上PTFE環，壓縮它直到閘板停在鋼制閥座上，這樣，就形成了雙重密封，首先是PTFE對金屬密封，然后是金屬對金屬密封，閥座也被牢固地撿到凹槽，在這一點，O形圈阻止任何后部介質流.
3、閥體壓力泄放后，形成進口密封，管道壓力作用于進口閥座，使其移向閘板，這時形成PTFE對金屬的密封，同時，O形圈與閥座凹槽形成緊密的密封.
4、閥門自動泄放多余的壓力，當閥體壓力大于管道壓力時，由于熱膨脹，進口閥座推向凹槽，閥體內多余的壓力在閥座與閘板之間泄放到管道中.
Flat valve principle of work:Double seal, automatic pressure release, free maintenance
1.Valve internal pressure quite, the disc in closing state, seating surface PTFE ring form the initial seal, every time open or close the valve, the valve seat ring can clean on both sides of the gate.
2.The valve pressure on management, the pressure in the role of ram, force it to close to export seat PTFE ring, compression of it until the disc stop in steel seat, so, they form a double seal, first is PTFE to metal seal, and then is the metal to metal seal, seat was also firmly pick up to groove, at this point, to prevent the o-ring any medium flow.
3.Pressure from the body of the valve bleeder, form the imported seal, line pressure in the role of import the seat, make its move to ram, then form of metal sealing PTFE, and at the same time, with the seat o-ring seal grooves form a tight.
4.Automatic relief valve put extra pressure, when the body pressure than the pipe pressure, due to thermal expansion, import seat into the groove, body excess stress in the seat and disc discharge pipeline in between.