When the level exceed limited height, the alarm send signals to start self-priming pump drain.

当水位超过限制高度时，发出信号启动自吸泵排水。

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There are well-designed pump drain back tank and is exposed in the work gear torque exerted the smallest, so bearing loads of small, wear, pump efficiency.

泵内有设计合理的泄油和回油槽，是齿轮在工作中承受的扭矩力最小，因此轴承负荷小，磨损小，泵效率高。

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Pump shaft seals use mechanical seal, pump top and bottom, respectively, equipped with water injection plug and the drain plug.

泵的轴封采用机械密封，泵体顶部和底部分别装有注水、放泄的螺塞。

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You add in the sump pump, the French drain, the alarm system, the slate roof, the gutters, the generator and you convince yourself that you're safe.

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There are some systems that actually will take a circle and drop it just below the surface of the water and have the oil kind of flow into it, almost like a drain, recover it and pump it out.

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