疏水閥在蒸汽加熱系統中起到阻汽排水作用，選擇合適的疏水閥，可使蒸汽加熱設備達到最高工作效率。要想達到最理想的效果，就要對各種類型疏水閥的工作性能、特點進行全面的了解。疏水閥的品種很多，各有不同的性能。選用疏水閥時，首先應選其特性能滿足蒸汽加熱設備的最佳運行，然后才考慮其他客觀條件，這樣選擇你所需要的疏水閥才是正確和有效的。疏水閥要能“識別”蒸汽和凝結水，才能起到阻汽排水作用。“識別”蒸汽和凝結水基于三個原理：密度差、溫度差和相變。于是就根據三個原理制造出三種類型的疏水閥：分類為機械型、熱靜力型、熱動力型。1.在生產工藝的換熱設備，烘干室，快速熱交換器，蒸餾設備等需要快速升溫，不允許存有凝結水的生產加熱設備，應該選用機械型疏水閥。2.在蒸汽管道，伴熱管線、小型加熱設備，采暖設備，溫度要求不高的用汽設備，應該選用熱靜力型疏水閥。3.在高溫高壓過熱蒸汽管線和設備上，應該選用過熱蒸汽專用疏水閥。

　　steam traps steam heating system in a waste gas drainage role in the selection of suitable steam traps allow steam heating equipment for the highest efficiency. To achieve optimal results, it is necessary for all types steam traps work performance and characteristics of a comprehensive understanding. steam traps many varieties, each with different performance. steam traps choice, should first elect their identity can best meet the steam heating equipment operation before considering other objective conditions, such choices you need steam traps is correct and effective.steam traps to be "identified" steam and condensed water can play a role in blocking air drainage. "identification" and the condensed steam water based on three principles : the poor density, and temperature difference of change. So on the basis of three principles of creating three types of steam traps : classified as mechanical type, thermal static type, thermal power-based. 1. In the heat production equipment, drying room, rapid heat exchangers, distillation equipment needs rapid warming, not a condensed water heating equipment production should be chosen mechanical type steam traps. 2. In steam pipes, coupled heat pipelines, small heating equipment, heating equipment, air temperatures do not ask for the use of equipment, it should be the choice of hot static type steam traps. 3. Overheating in high-temperature high-pressure steam pipelines and equipment, should choose an exclusive steam traps steam