Valve Seat Assembly for Low-Pressure Bidirectional Sealing

The biasing members are compressed in advance using a compression tool before the gate is installed. This preliminary compression creates the necessary space between seats for gate installation, and the biasing members maintain this compressed state during assembly. After the gate is installed, the biasing members are released to provide continuous sealing force on both sides of the gate, thereby improving sealing reliability without permanently complicating the assembly process.

The biasing members continuously urge the seats against the gate throughout operation, maintaining constant engagement between the sealing surfaces. This continuous contact prevents contamination and particulate matter from entering the sealing interface, and eliminates gaps where abrasion could occur. The biasing force ensures the seats remain pressed against the gate whether the valve is open or closed, thereby maintaining sealing surface integrity while preserving design simplicity.

The constant engagement of sealing surfaces maintained by the biasing members eliminates gaps between the seats and gate. This continuous contact creates a barrier that prevents grease from migrating from the valve interior to the fluid stream. With no gap to traverse, grease remains contained within the valve body, maintaining lubrication effectiveness throughout operation while preventing substance loss to the external environment.

The biasing members provide a counteracting force that pushes the seats against the gate independently of fluid pressure. This active urging force compensates for the lack of pressure-driven sealing force during low-pressure operation. Whether the valve operates at high or low pressure, the biasing members maintain sufficient sealing force by mechanically urging the seats into contact with the gate, thereby ensuring reliable sealing across the entire pressure range and improving versatility without sacrificing sealing performance.