Second: to assist in cutting out a boiler, when ceasing to fire. In this case, the disc automatically closes and prevents header pressure from entering the boiler.

其次，有助于切断锅炉，当停火后，阀瓣自动关闭，防止热水器压力进入锅炉。

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Furnace web of water supply mainly refers to before entering the steam boiler, in order to remove the hardness of the softening treatment and alkali reduction, in addition to salt water.

炉外水处理主要指给水在进入蒸汽锅炉之前，为了除去其中的硬度而进行的软化处理以及降碱、除盐等水质处理。

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He worked as a delivery boy, a lather boy, a lift boy and a bell boy before entering the housepainting trade, mastering the crafts of graining and marbling just in time to be enlisted as a boiler-stoker in the Second World War.

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