隔膜阀是一种特殊形式的截断阀，其启闭件是一块用软质材料制成的隔膜，它将阀体内腔与阀盖内腔隔开。隔膜阀实际上不过是“钳夹”的阀，一个弹性的，可扰的膜片，用螺椿连接在压缩件上，压缩件是由阀杆所操作而上下移动，当压缩件上升，膜片就高举，而造成通路，当压缩件下降，膜片就压在阀体堰上（假使为堰式阀）或压在轮廓的底部（假使为直通式），隔膜阀适用于开关及节流之用。
隔膜阀本身结构设计的原因特适合于超纯介质或污染严重，十分粘稠的液体、气体、腐蚀性或惰性介质。与控制设备相结合时，隔膜阀更能取代其它传统控制系统，尤其是适用于固体和易污染的惰性介质。产品主要应用于生物制药、食品、行业; 以及电力、化工、电镀、等行业的工业水处理中, 还被应用于半导体晶圆的生产中,隔膜阀是特别适用于运送有腐蚀性，有粘性的流体，例如泥浆、食品、药品、织维性粘合液等，因管线中，隔膜阀的操作机构，是不暴露在运送流体中，故不具污染性，也不需要填料，阀杆填料部也不可能会泄漏。
diaphragm valve is a special form of cut-off valves, which open and close this is a piece of soft quality materials produced by the divide, it separate the inside body and inlet inside the cover. diaphragm valve is really only "jaw" valves, a flexible, three of diaphragm by Lo underground link in compressed pieces, the compression of which is operated by stem next movement when compressed pieces rise diaphragm on hold, resulting in access, when compressed pieces falling, diaphragm pressure on the weir in valve body (even for the weir-type valves) or pressure at the bottom contours (even for straight-through processing), diaphragm valve applicable to switches and reducing use.
diaphragm valve own special reasons for the structural design suitable for super pure medium or severe pollution very ropy liquids, gases, corrosive or inert medium. Combined with control equipment, diaphragm valve replace other more traditional control systems, especially vulnerable pollution applicable to solid inert medium. Biological products are mainly used in the pharmaceutical, food, industry; And the power, chemical, electroplating, and industrial water treatment industries, was also applied to the semiconductor wafer production, diaphragm valve particularly applicable to the delivery of a corrosive, became the fluid, such as mud, food, medicines, woven together liquid-dimensional, because pipelines, diaphragm valve operating agencies, it is not exposed to the delivery of fluid, So no polluting, and do not need to fill, the Department can not fill stem will leak.
