译文：
1、活塞式止回阀的阀瓣呈圆盘状，绕阀座通道的转轴作旋转运动，因阀内通道成流线形，流动阻力比升蝶式止回阀小，适用于低流速和流动不常变化的大口径场合，但不宜用于脉动流，其密封性能不及升降式。蝶式止回阀分单瓣式、双瓣式和多半式三种，这三种形式主要按阀门口径来分，目的是为了防止介质停止流动或倒流时，减弱水力冲击。 2、活塞式止回阀瓣沿着阀体垂直中心线滑动的止回阀，内螺纹止回阀只能安装在水平管道上，在高压小口径止回阀上阀瓣可采用圆球。蝶式止回阀的阀体形状与截止阀一样（可与截止阀通用），因此它的流体阻力系数较大。其结构与截止阀相似，阀体和阀瓣与截止阀相同。阀瓣上部和阀盖下部加工有导向套简，阀瓣导向简可在阀盏导向简内自由升降，当介质顺流时，阀瓣靠介质推力开启，当介质停流时，阀瓣靠自垂降落在阀座上，起阻止介质逆流作用。直通式蝶式止回阀介质进出口通道方向与阀座通道方向垂直；立式升降式止回阀，其介质进出口通道方向与阀座通道方向相同，其流动阻力较直通式小。 3、活塞式止回阀：阀瓣围绕阀座内的销轴旋转的止回阀。碟式止回阀结构简单，只能安装在水平管道上，密封性较好。 4、活塞式止回阀：阀瓣沿着阀体中心线滑动的阀门。管道式止回阀是新出现的一种阀门，它的体积小，重量较轻，加工工艺性好，是止回阀发展方向之一。但流体阻力系数比旋启式止回阀略大。 5、压紧式止回阀：这种阀门是做为锅炉给水和蒸汽切断用阀，它具有升降式止回阀和截止阀或角阀的综合机能。 此外，还有—些不适用于泵出口安装的止回阀，如底阀、弹簧式，Y型等止回阀。

“ Piston Check Valve Installation ”是由提供的国际阀门新闻，译文仅供参考。另外，中国止回阀网还提供相关产品搜索：、、、、等。

原文：
1, the valve piston valve cylindrical valve discs, valve seat around the channel axis for rotation, because the valve channel into a streamlined, flow resistance ratio rose butterfly valve, suitable for low flow rate and flow changes in large-caliber seldom occasions, but not for the pulsating flow, the sealing performance is less than lift. Butterfly Check points unicuspid type, two-valve type, and most of type three, three by the valve diameter to form the main points, the purpose is to prevent the media to stop flow, or reflux, the weakening of the hydraulic shock. 2, piston check valve flap along the vertical center line of sliding valve check valve, check valve with internal thread can only be installed in horizontal pipes, in the high-pressure small-bore ball valve on the valve flap can be used. Butterfly valve of the same body shape and cut-off valve (with valve common), so it is more fluid drag coefficient. Similar to its structure and cut-off valves, valve body and disc with the same cut-off valve. Disc upper and lower valve cover set-oriented processing with Jane, Jane can guide the valve flap valve within the free light-oriented simple movements, when the medium downstream, the valve flap to open by media thrust, when the media stop flow, the valve flap by self- vertical landing on the seat, stop the media from the upstream role. Butterfly valve straight-through media channels import and export channel perpendicular to the direction of the valve seat; vertical lift check valve, the direction of its media access import and export channel in the same direction with the valve seat, the flow resistance is smaller than the straight-through. 3, piston-type check valve: valve within the valve seat around the valve pin rotation. Simple disc check valve, can only be installed in horizontal pipe, sealing well. 4, piston-type check valve: valve valve slide along the centerline of the valve body. Pipe-type check valve is emerging as a valve, its small size, light weight, good processing technology is the development of non-return valve. But the fluid drag coefficient slightly larger than the swing check valves. 5, compression-type valve: This valve is used as boiler feed water and steam off with a valve, it has a lift check valve and stop valve or angle valve integrated function. In addition, there are - some do not apply to pump non-return valve installed, such as the bottom valve, spring-, Y-type and other non-return valve.