Gearboxes are important accessories for butterfly valves, especially in applications where manual operation is required or where the torque required to actuate the valve is high. Gearboxes provide mechanical advantage by converting the input force into a higher output torque, making it easier to operate the valve. Here’s an overview of industrial gearboxes used with butterfly valves:

1. Manual Gearboxes: Manual gearboxes are operated by hand and are commonly used in applications where frequent adjustments or fine control of the valve position are necessary. They consist of gears and a handwheel that allow operators to open or close the valve by rotating the handwheel. Manual gearboxes come in various configurations, including worm gear, bevel gear, and spur gear designs.

2. Worm Gearboxes: Worm gearboxes are one of the most common types used with butterfly valves. They consist of a worm (a screw-like gear) and a worm wheel (a cylindrical gear). When the input shaft (connected to the handwheel) is rotated, the worm rotates the worm wheel, providing a high output torque with relatively low input force. Worm gearboxes offer smooth operation and are well-suited for applications requiring precise positioning.

3. Bevel Gearboxes: Bevel gearboxes use bevel gears to transmit power between shafts that are at an angle to each other. They are commonly used in applications where the valve stem is oriented horizontally, and the handwheel needs to be operated vertically. Bevel gearboxes provide efficient power transmission and are often used in tight spaces where a right-angle drive is required.

4. Spur Gearboxes: Spur gearboxes use spur gears (straight-cut gears) to transmit power between parallel shafts. They are simple in design and offer high efficiency in power transmission. Spur gearboxes are suitable for applications where the valve stem is oriented vertically, and the handwheel is operated horizontally. They provide reliable operation and are commonly used in industrial settings.

5. Multi-turn Gearboxes: Multi-turn gearboxes are used in applications where the valve requires multiple turns to fully open or close. They are designed to provide the necessary mechanical advantage to operate valves with multiple turns of the handwheel. Multi-turn gearboxes may incorporate worm, bevel, or spur gears, depending on the specific requirements of the application.

6. Quarter-turn Gearboxes: Quarter-turn gearboxes are designed for butterfly valves and other valves that require only a quarter-turn (90 degrees) to fully open or close. They provide the necessary torque to actuate the valve with minimal effort. Quarter-turn gearboxes are often used in large-diameter valves and in applications where quick operation is required.

7. Enclosed Gearboxes: Enclosed gearboxes are designed to protect the gears from dust, dirt, moisture, and other contaminants present in the operating environment. They are sealed units that provide reliable performance and require minimal maintenance. Enclosed gearboxes are commonly used in outdoor or harsh industrial environments.

8. Weatherproof Gearboxes: Weatherproof gearboxes are designed to withstand exposure to extreme weather conditions such as rain, snow, and temperature variations. They are constructed from durable materials and are often equipped with seals and gaskets to prevent water ingress and corrosion. Weatherproof gearboxes are suitable for outdoor installations or applications where the valve is exposed to environmental elements.

9. Corrosion-resistant Gearboxes: Corrosion-resistant gearboxes are designed for use in corrosive environments where exposure to chemicals or corrosive substances may degrade standard gearbox materials. They are constructed from corrosion-resistant materials such as stainless steel or coated with protective coatings to withstand corrosion and prolong service life.

10. High-Temperature Gearboxes: High-temperature gearboxes are designed to operate in high-temperature environments where standard gearboxes would fail. They are constructed from heat-resistant materials and are equipped with specialized lubricants and seals to withstand elevated temperatures. High-temperature gearboxes are commonly used in applications such as steam service or hot gases.

These are just a few examples of the various types of gearboxes used with butterfly valves in industrial applications. The selection of the appropriate gearbox depends on factors such as the valve size, torque requirements, operating environment, and specific application requirements.