Flat valve seat

The sealing structure of the expansion valve seat belongs to the technical field of throttling devices for steam compression heat pump systems. It mainly includes a valve body, an adjusting screw with a balance spring set at the lower part of the valve body, a sealing nut set at the bottom of the valve body, a rubber sealing ring between the adjusting screw and the valve body, a sealing ring between the sealing nut and the lower end face of the valve body, or a direct contact seal between them. The sealing structure of the expansion valve seat is reasonable and simple. The setting of the sealing nut and the dual sealing structure between the sealing nut and the valve body, as well as between the adjusting screw and the valve body, ensure good sealing performance and adjustment sensitivity. Under any operating conditions, it has high cooling (heating) capacity and high energy efficiency.