Steam drainage device

A steam drainage device as an auxiliary device of a main steam pipeline comprises a liquid collecting pipe, a pipe cap, a liquid discharging pipeline, a drain pipe, a filter and a drainage valve, wherein the liquid collecting pipe vertically welded below the main steam pipeline is communicated with the main steam pipeline, the pipe cap is arranged at the bottom of the liquid collecting pipe; the liquid discharging pipeline is connected to the position of a hole at the bottom of the pipe cap, the drain pipe is connected to the lateral surface of the lower portion of the liquid collecting pipe, and the filter and the drainage valve are sequentially mounted on the drain pipe along the direction of water flow. The steam drainage device has the advantages that condensed water can be drained from a pipeline at the bottom of the liquid collecting pipe at the early stage of operation, impurities such as original rust, welding slag and the like inside the main steam pipeline can be discharged along with the condensed