1 引言小型直流式蒸汽锅炉,由受热面管子竖直排列组成,除上下集箱外,全部受热面管子均为上升管,给水泵从下集箱向管子一端供水,按预热段、蒸发段顺次贯流,从管子的另一端产生出所需要的蒸汽。由于直流式锅炉具有受热面大,金属耗量小,因而实现了锅炉小型化,锅炉房占地面积小。另外,直流式 1 Introduction Small-scale direct-flow steam boilers, heating pipes by the vertical arrangement of vertical tubes, except for the upper and lower headers, all heating surface tubes are riser, feed pump from the header to the end of the tube water, according to the preheating section, evaporation section Consecutive flow through, from the other end of the tube to produce the required steam. Because the DC boiler has a large heating surface, metal consumption is small, thus achieving the boiler miniaturization, boiler room covers an area of ​​small. In addition, DC type