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- pyeloparenchymal backflow 肾盂实质回流
- 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。
- 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。
- This would create an air gap to eliminate any possible backflow. 这将产生一个气隙以消除任何可能的回流。
- 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 system should be flushed before the backflow valve is installed. 在安装防回流阀之前，系统应该进行冲洗。
- 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。
- Certified testers of backflow assemblies must conduct this confirming test. 这类检测必须由有资格证书的检测人员进行。
- Slowly open upstream shutoff and allow the backflow preventer to fill slowly. 慢慢开启上游关闭阀，让防回流阀慢慢注水。
- Backflow preventer manufactured from 300 Series stainless steel for corrosion resistance. 防回流阀采用耐腐蚀的300系列不锈钢制造。
- A strainer should be installed as shown, ahead of backflow preventers to prevent discs from unnecessary fouling. 应该如图所示在防回流阀前安装一个过滤器，防止阀瓣出现不必要的污垢。
- A strainer should be installed as shown, ahead of the backflow preventer to prevent discs from unnecessary fouling. 应该如图所示安装一个过滤器，安装位置位于防回流阀之前，以防止不必要的污染。
- The user installs a dual check backflow preventer at the water meter as prescribed by the supplier of safe drinking water. 用户要由安全饮用水供应商在水表处安装法定的双止回防回流阀。
- Designed to retrofit backflow protection onto fire hydrants used for temporary water service. 适用于用在临时性水应用的消防栓上的防回流阀的更新改造。
