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- 第一止回阀受到污染;或The first check valve is fouled; or
- 建议在防回流阀前安装一个过滤器，防止止回阀受到污染和阀门在再增压期间出现泄漏或溢出。The installation of a strainer ahead of the backflow preventer is recommended to prevent fouling of the check assembly and resultant spillage from the valve during repressurizing.
- 第一first
- 如果下游止回阀受到污染,则可能从排气口泄漏到大气中,因此止回阀总成就要位于出现故障时能够清晰可见的位置。In the event of fouling of the downstream check valve, leakage would be vented to atmosphere thereby providing a visual indication of failure of the check assembly.
- 第一次first
- 拆卸固定第一止回阀阀盖的四个螺丝。Remove the four screws holding the first check valve cover.
- 受到receive
- 污染pollution
- 第一个first
- 第一章chapter one
- 组件包括:第一止回阀总成和阀盖O形环。Kit includes: First check assembly and Cover O-ring.
- 环境污染environment pollution
- 污染的infectant
- 止回阀check valve
- 第一步step one
- 空气污染air pollution
- 第一时间very first time
- 白色污染white pollution
- 第一名gold medal winner
- 第一的prima
