Spring-actuated valve to be used on pump discharge. Swing check with outside lever and spring to be used on sump, sewage and storm drain lines.

弹簧执行机构止回阀用于管道排放。外置操作手柄和弹簧执行机构的旋启式止回阀用于污水坑、排污和雨水排泄管道。

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He added that sewerage upgrades carried out at pumping stations in 2001 were operating at peak capacity during the storm and that a stand-by pump had also been switched on.

BBC: Promise to act after flood damage