主要用于氣體、大口徑水管線及蒸汽等介質管路中, 防止倒流, 控制閥啟閉部件除靠介質流動自行關閉以外，還通過彈簧復位執行機構強制關閉，以避免關閉力矩不夠，倒流帶來危害，工作壓力高時，還可加裝液壓緩閉裝置，防止水錘、氣錘損害設備。

主要特點：

閥體采用大偏心的三偏心蝶型閥結構，蝶板形成重錘自動關閉。
不需要外加重錘，減少流阻損失，通過彈簧復位氣缸，提供力矩助關。
金屬密封啟閉零泄漏，耐沖涮，抗創擊，必要時加裝，液壓緩閉系統。 
介質回流壓力加上彈簧助關，確保閥門止回的密封性能。
角行程動作，軸向填料密封確保不滲漏 。

It mainly used to pipeline on gas, steam and so on to prevent regorging.Depending on the operating medium itself to close, besides, it can be closed forcibly by the spring return actuator, avoiding dangerous by flow backwards. If the working pressure is too high, we can fix hydraulic pressure sets to prevent water hammer and air hammer from damaging equipments.
 
Main characteristic: 
The body valve is three eccentric butterfly structures, the disc can became a hammer to close automatically. 

Reducing flow block without hammer. Spring return cylinder helps to offer torque.

Metal seated reaches zero leakage
Flow backwards of operating medium and spring return guarantees valve’s seal.
Angle action 

氣動金屬密封蝶型主動式止回閥
Metal seated Butterfly pneumatic check valve
 
結構性能特點structure characters

 
大偏心軸設計形成重錘自動關閉
在三偏心結構基礎上，閥軸偏置距離加大，將蝶板一端形成重錘，可以自動關閉閥門，同時加裝輔助氣動彈簧關閉系統，在介質回流壓力不夠時，在未回流前將蝶板預先關閉，確保止回和減免水錘現象的發生。
  
Eccentric axial design
　On the base of the Eccentric triple structure, it makes the stem wider than before, which produce a hammer makes the valve close automatically. At the same time, it sets assistant pneumatic spring system, ensures safety and decrease water hammer.

無滑動磨損實現長壽命

斜錐面金屬密封蝶閥設計采用了一個雙偏心和一個特殊斜錐橢圓密封結構，實現蝶板在開啟瞬間密封面即分離，關閉接觸即密封的效果，這種密封結構實現啟閉無機械滑動摩擦，大大延長了密封件的使用壽命, 并且達到啟閉輕松自如目的，且具有密封自動補償功能。

No slip friction Realizing long service life.
The Metal seated butterfly valve adopts a double eccentric structure and a inclined cone seal. The seal-ring can be separated once open the disk, and the valve can be sealed once the seal-ring contacts the disk. This structure can decrease the friction torque when the butterfly valve opens and closes, and expanded the life time, and make opening and closing easily. 

斜錐面金屬密封實現零泄漏
斜錐面金屬密封蝶閥是采用專利技術結構形式的金屬密封蝶閥：采用了可浮動的密封環，密封環在閥體上可以依閥板關閉時推力適當調整自身的位置，這樣可浮動的密封可以補償閥門在不同工況（如高溫）下產生的變形、熱膨脹等因素，消除了對密封面的變形的影響，確保密封吻合、比壓均勻，確保金屬硬密封的密封效果。這種結構從本質上徹底解決了溫度變化時密封泄漏的難題，實現零泄漏。

Sideling Cone Metal Sealing Realizing Zero Leakage
Triple Eccentric Metal-seated Butterfly Valve absorbs the advantages in this field and holds its unique construct characteristics: floating seal ring is adopted and the seal ring is capable of self-adjustment by the pressure of disc when closing so as to compensate the possible deformation or heat expansion under different working conditions (e.g., high temperature) to avoid damage to the seal face, resulting an even contact pressure ratio, a long service life and an improved [the] metal sealing. So, the seal leakage problem as a result of temperature changes is solved completely.

可加裝液壓緩閉功能

在流量大，回流沖擊的情況下，可以加裝液壓微阻緩閉裝置，在止回閥快速關閉閥到最后10°時，液壓微阻機構發揮作用，使之緩慢關閉最后10°，防止了水錘及撞擊的發生。在回流小，口徑小的情況下，不需加裝此機構。

Liquid pressure makes the closing speed slow when the flow is strong or the circumfluence is strong, we can install this kind of stes.The check valve close fast the last 10 degree, and this kind of sets makes it close slowly, so as to prevent making water hammer. It is not necessary to install such kind of sets when the circumfluence is weak or the caliber is small.