History of Pneumatic Flanged Ball Valves

The pneumatic flanged ball valve evolved from the plug valve and shares the same 90-degree rotary action; the key difference is that the plug element is a sphere featuring a circular bore or passage along its axis. The proportions of the spherical surface and the port openings are designed so that a 90-degree rotation presents the spherical surface entirely at the inlet and outlet, thereby shutting off the flow. This design retains the rapid opening and closing capabilities of the plug valve while gaining widespread adoption due to superior sealing performance and lower fluid resistance.