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- backflow prevention device 防回流装置
- Four required per backflow preventer. 每个防回流阀需要四个。
- Winterization of backflow preventers. 防回流阀的过冬处理。
- State-of-the-art accuracy of .25% of full scale for reliable testing of all types of backflow prevention assemblies. 最新技术的精确度，达全量程的0.;25%25，适用于所有类型防回流阀总成的可靠检测。
- Annual inspection is required of the strainer and the backflow preventer to insure proper operation of the device. 要求对过滤器和防回流阀进行年度检查，以确保装置的性能正常。
- For use with backflow preventer test cocks to protect from damage. 用于防回流阀测试旋塞，防止受到破坏。
- A check valve may be required ahead of the backflow preventer. 此时在防回流阀前面可能需要安装一个止回阀。
- Strategically placed doors provide access to the backflow prevention assembly for testing and repair without removal of the entire unit. 永久性配置的门便于接近防回流阀总成进行检测和不拆卸整个装置的情况下进行维修。
- The device should not be installed inside a wall or in a concealed location. Copper tubing shall not be used on the downstream side of the backflow preventer. 这种装置不应该安装在墙内或隐蔽的位置。在防回流阀下游不能采用铜管。
- The Figure 85 and 90M are designed to employ an integral back-flow prevention device to prevent potential back-siphonage. 型号85和90M结构上配置一个一体式防回流装置，用以防止潜在的反虹吸现象。
- The backflow preventer must be installed upstream of the regulator. 防倒流装置必须安装在调节阀的上游位置。
- The dual check backflow preventer shall meet ASSE 1024. 这种双止回防回流阀应该满足美国卫生工程师协会(ASSE)1024标准。
- Also, mechanical backflow preventers and air gaps can be bypassed. 此外，机械式防回流阀和气隙可以作为旁路。
- UL/FM approved backflow preventers must include UL/FM approved OSY. FM认证防回流阀必须包括UL/FM认证外阀杆轭架。
- The fuel regulator surge prevention device is a actuating unit which control fuel supply of the first and second fuel path of the main chamber when the engin is working. 摘要燃油调节器防喘装置是实现发动机工作过程中控制发动机主燃烧室主、付油路供油的执行装置；
- Important: The device should not be installed inside a wall or in a concealed location. Copper tubing shall not be used on the downstream side of the backflow preventer. 重要提示:这种装置不应该安装在墙内或隐蔽的地方。在防回流阀的下游不应该使用铜管。
- Property damage due to relief valve discharge that can occur due to dirt and debris within the valve or a mechanical failure within the backflow prevention assembly. 阀门内的污垢和碎片，或者防倒流总成内的机械故障可能导致安全阀排放，从而导致财产损失。
- The relief valve may be serviced while on or off the backflow preventer valve. 可以在防回流阀上维修安全阀，或将其从防回流阀拆卸下来维修。
- Installing a backflow preventer in a pit or vault is not recommended. 不建议在坑内或拱顶内安装防回流阀。
