对于锅炉厂的安全运行来说，截止止回阀和其它附加在锅炉上的安全阀或其它安全设施一样是必不可少的。这种阀门在锅炉蒸汽管线中能够执行四项重要的功能。
　　Stop Check Valves are as essential to safe operation of a boiler plant as safety valves or other safety devices attached to the boiler. The valves are intended to perform four important functions in boiler steam piping.
　　首先，能过作为一个自动逆止阀，防止蒸汽从主蒸汽加热器上倒流到锅炉里。
　　First: to act as an automatic non-return valve by preventing a backflow of steam from the main steam header to the boiler.
　　其次，有助于切断锅炉，当停火后，阀瓣自动关闭，防止热水器压力进入锅炉。
　　Second: to assist in cutting out a boiler, when ceasing to fire. In this case, the disc automatically closes and prevents header pressure from entering the boiler.
　　第三，在关闭后，有助于将锅炉带进应用管路系统中。这种操作在手工进行时，要求特别小心谨慎，但是采用截止止回阀则可以自动进行，而不会产生压力波动或水位扰动。
　　Third: To assist in bringing a boiler into service after a shutdown. This operation requires considerable care when performed manually, but is accomplished automatically by a stop check valve, without pressure fluctuations or disturbance of the water level.
　　第四，通过防止蒸汽从热水器倒流的“安全第一”的阀门，或用于在检查或维修时关闭管路，维护人员应该偶尔开启阀门。
　　Fourth: To act as a “safety first” valve by preventing backflow of steam from the header or for shutdown for inspection or repairs, should an attendant accidently open the valve.
　　如果连接主蒸汽热水器的锅炉不止一个，则在每个锅炉与热水器之间的管路上都应该安装一个截止止回阀。
　　When more than one boiler is connected to the main steam header, a stop check valve should be installed in the pipeline between each boiler and the header.
　　这种阀门安装时，应该使得锅炉内的压力位于阀瓣下方。直立阀可以用在水平管路或流向向上的垂直管路上。角形阀可以用在向上水平或水平向下的流体管路上。
　　The valve should always be placed so that the pressure in the boiler is under the disc. Straightway valves may be used in horizontal or vertical lines for upward flow. Angle valves may be used for upward horizontal or horizontal downward flow.

注释
Notes

　　圆柱形阀瓣是唯一一个活动部件。这是一种能够在最小流速下产生最大提升力的基本结构。没有侧翼导轨，因此不会产生“旋转”合力从而加快磨损。
　　Cylindrical-Shaped Disc is the only moving part. It is especially designed to produce maximum lift at minimum velocities. There are no wing guides to cause “spinning” with resultant rapid wear.
　　长节流唇位于阀瓣上，当流体接近阀座密封位置时可以阻止减速流体，从而防止阀瓣颤动，减轻阀座密封面的拉丝现象。
　　Long Throttling Lip on the disc retards flow when seating position is approached. Disc chattering is prevented, and wiredrawing of seating surfaces is reduced.
　　可拆衬套在整个行程中引导阀瓣。这个部件完全独立于阀体，因此不会受到膨胀应力的影响而产生变形。
　　Removable Liner guides the disc throughout the full travel. Being entirely independent of the body, it is not subject to distortion by expansion strains.
　　活塞环加强的减震器的性能，避免阀瓣迅速的运动，如果脉冲现象特别强烈，则可能需要安装两个活塞环。
　　Piston Ring adds to dashpot's ability to avoid rapid disc movement and where pulsations are extremely severe, two piston rings can be installed.
　　易于再研磨的攻丝轮毂位于阀瓣顶部，允许插入管嘴或有眼螺栓，促进阀瓣迅速拆卸下来进行研磨。
　　Easy Regrinding Tap Bosses on top of the disc permit inserting nipples or eye bolts to facilitate quick removal of the disc for grinding.
　　超大端口面积位于阀腔内，使得通过阀门的压降最小，确保阀瓣的无限制移动。
　　Large Port Areas in the liner produce only a minimum of pressure drop through the valve and assure unrestricted movement of the disc.