Worm Gear Butterfly Valves: Introduction, Differences from Lever Butterfly Valves & Advantages

Worm Gear Butterfly Valves are a type of butterfly valves composed of a worm gear head and a butterfly valve body. They fall into the category of Manual Butterfly Valves according to the actuation method and require manual operation. Specifically, manual operation involves rotating the handwheel on the worm gear head to control the opening and closing of the butterfly valve.

Differences Between Worm Gear Butterfly Valves and Lever Butterfly Valves

Although both belong to Manual Butterfly Valves, the worm gear butterfly valves have a wider application range and more uses compared with lever butterfly valves. The reason is that lever butterfly valves are limited by the operating torque and are only suitable for occasions where the pipe diameter is less than DN250mm. If the diameter is too large beyond this range, manual opening and closing will become very difficult, and may even lead to lever breakage. Due to the equipped worm gear head, the worm gear butterfly valves are driven by the worm gear to make the opening and closing of the butterfly valve more labor-saving. Therefore, the worm gear-driven butterfly valves are very suitable for both small and large diameters.

Advantages of Worm Gear Butterfly Valves

• The protection class of the worm gear box reaches IP65.

• The worm gear box undergoes regular dust-proof and spray-proof type tests to ensure reliable product protection performance.

• The worm gear box undergoes strength tests: applying a force of 890N to the edge of the handwheel end, no damage or deformation occurs in any part of the worm gear head.

• The worm is made of 45# steel with quenching and tempering treatment, featuring good comprehensive mechanical properties and long service life.

• The connecting pin between the worm and the worm shaft is made of 45# steel with quenching treatment, ensuring high strength and reliable connection.

• The fasteners between the box cover and the box body adopt a combination of hexagon head bolts, spring washers and flat washers, facilitating disassembly and assembly and reliable connection.

• The worm gear is processed with a special worm gear hob, ensuring tight and reliable fitting, wide contact surface and small friction force. At the same time, the worm gear can be freely loaded and unloaded, facilitating installation.

• The worm gear and worm adopt positive modification, with thicker tooth thickness, good rigidity and large transmission limit torque.