Trap is used in steam pipe network and equipment, can automatically discharge condensate, air and other non-condensable gas, and water vapor leakage valve. Trap function: Only steam is required on equipment that uses and utilizes steam. Condensation water is sure to be produced in such equipment, and condensate is a detrimental fluid, mixed with air and other non-condensable gases, which can cause equipment failure and performance degradation. In this case, the most important function of traps in the following three aspects: (1) can quickly rule out the resulting condensate. (2) to prevent steam leakage. (3) exclude air and other non-condensable gas.