止回阀

例句：

1. 1. The stop-flow valve is used to prevent the flow of fluids during maintenance.
   止回阀用于在维护期间防止流体流动。
2. 2.The valve controls the flow of gases through the pipeline.
   阀门控制气体通过管道的流动。
3. 3.The valve was designed to ensure that the system could operate smoothly even under high pressure.
   阀门被设计成即使在高压下也能确保系统能够顺畅运行。