Trap is used in steam pipe network and equipment, can automatically discharge condensate, air and other non-condensable gas, and water vapor leakage valve. According to the different working principle of the trap valve steam trap can be turned into the following three types: Mechanical type: Rely on the steam trap condensate level changes in the action of Wei Wei, including: Float type: float closed hollow Ball open up Float: Float open to the bucket up Open downward Float: the float is open downward Barrel type Static type: Rely on the liquid temperature changes and actions, including: Bimetal: sensitive original For the bimetallic vapor pressure type: sensitive original bellows or ink cartridges, filled with volatile liquid inside Thermodynamic: Rely on the thermodynamic properties of the liquid changes. Disc type: Because of the same pressure, the flow rate of liquid and gas are different, resulting in different dynamic and static pressure to drive the disc valve action. Pulsed: Due to the different temperatures of the condensate through the bipolar series orifice plate, sitting in the bipolar orifice orifice between the different pressures, driving the valve action.