company news about Why can a butterfly valve become tighter under increasing pressure?

  A standard butterfly valve is a “center-mounted butterfly valve,” in which the valve stem passes through the center of the disc. With this design, the disc and rubber seat are in constant contact during opening and closing, leading to wear and tear, and the valve is prone to leakage under high pressure.

  To solve this problem, engineers invented the “eccentric butterfly valve.” By offsetting the valve shaft from the center, the valve disc only makes contact with the seal at the very last moment of closure. The most advanced of these is the triple-eccentric metal hard-seal butterfly valve:

  How it works: Through a geometric eccentric design in three different dimensions, the butterfly disc follows a “cam-like” trajectory as it closes.

  The remarkable effect: The tighter it closes, the tighter it seals—not through friction, but through compression! The higher the fluid pressure in the pipeline, the tighter the disc is pressed against the seat, achieving perfect “zero leakage.” This innovation has allowed the butterfly valve—which was originally limited to water supply applications—to dethrone the gate valve and break into the high-temperature, high-pressure petrochemical sector.