此外，第一和第二止回模块是相同的，可以互换。
Also, the first and second check module are identical and can be interchanged.
可安装止回阀或订制自带止回功能的阀。
Can be installed or custom built non-return valve function of the valve.
安装在阀门内的止回模块其阀座应该面对阀门进口。
Check modules are installed in the valve body with the seats facing the valve inlet.
倒流的流体通过倒流的流体压力将止回关闭装置与阀体紧密密封，从而实现阻止倒流的“止回”功能。
Reversed flow is stopped or held in "check" by fluid backflow pressure which seats the closure device against the valve body.
文中分析认为较经济而可行的方法是在支流下游设立止回闸，防止河水倒流从而保护支流水体。
A suggest is put forward after investigation and analysis that a return flow prevention gate be built for the benefits of economy and environment.
两个止 回阀和安全阀的阀座和阀座阀瓣应该是可更换的，更换过程不需要特殊工具。
Seats and seat discs shall be replaceable in both check valves and the relief valve without the use of special tools.
可安装止回阀或订制自带止回功能的阀门。
Can be installed check valve or custom comes with a return function of the valve.
本发明中的止回装置既可采用单向棘 爪棘齿式离合装置，也可以采用单向滚柱超越离合器。
The block device in the invention can adopt one-way pawl-ratchet type on-off devices and one-way roller overrunning clutches.
本发明中的止回装置既可采用单向棘 爪棘齿式离合装置，也可以采用单向滚柱超越离合器。
The block device in the invention can adopt one-way pawl-ratchet type on-off devices and one-way roller overrunning clutches.
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