The in-line spring-actuated lift check also is referred to as the "silent check" because the spring closes the valve before gravity and fluid reversal can slam the valve closed.

由于这种止回阀能够在重力和介质倒流撞击启闭件之前关闭阀门，因此这种直通弹簧驱动升降式止回阀也称为“静音”止回阀。

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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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