A worm gearbox is a type of gear system that uses a worm (a screw-like gear) and a worm wheel (a gear similar to a spur gear) to transmit power between non-parallel, non-intersecting shafts, typically at a right angle. These gearboxes are known for their high torque output and compact design.
When used for mounting on valves, worm gearboxes are designed to facilitate the manual or motorized operation of quarter-turn valves, such as butterfly, ball, and plug valves. These gearboxes are mounted directly onto the valve stem and convert the rotational motion from the handwheel or motor into the necessary motion to open or close the valve.

• The SBWG model is suitable for use with Butterfly, Plug and any other type requiring quarter turn motion for thrust and torque applications
• High Tensile Aluminium bronze material providing corrosion and abrasion resistance
• Castings are Ductile Iron, class 65-45-12 providing high strength and impact resistance
• Housing Covers have “Close-Open-Close” cast directly on the cover witch permits operation in either clock or anti clock close direction with position indication
• Also the pointer and easily be repositioned and adjusted with ease if required
• All units are furnished with removable splined bushings to permit accurate position between the gear drive and the valve shaft
• The drive sleeve is furnished with hardened steel thrust washers above and below the worm gear that minimize fiction loose between the gear and ductile iron castings
• Gears are machine cut, heat treated and ground for optimum operation
• The unit is completely O-Ring sealed suitable for temporary submersion to meet IP68 Class
• External Adjustable Stopper bolts allow for easy position accuracy of +/-5°. Each bolt also includes Buna-N sealing washers to pre-vent waster ingress
• This series of Worm Gears range from 310Nm to 540,000Nm with larger models available upon request
• Many options are available, such as hand wheels, chain wheels, position dial indicators, vertical input.