A slew drive is a type of gearbox that is critically designed to handle high axial, radial, and tilting moment loads while providing high rotational output torque. Across different applications, a slew drive can also be known as worm gear drive, slewing drive, turret bearing, worm drive, rotational unit, and many other slewing product labels. The mechanics behind it is built on the concept of a worm wheel where a slewing ring with external teeth is meshed with complementing worm gear with a predefined gear ratio. Internal components are contained and assembled inside a cast iron or aluminum housing for protection and installation.
The unique design of a slew drive allows it to utilize two perpendicular planes transmitting high output rotational torque with a relative speed ratio to its inputs. As the worm gear rotates through a low input torque on the horizontal plane, its hardened teeth translate rotational motion onto the external slewing teeth. This force creates a rotation around the perpendicular axis of the slew drive through the slewing outer ring. The use of a worm-wheel design makes room for a wide range of low torque inputs to the slew drive to transmit or hold high torque applications. Slew drives can be found across several constructions and heavy machinery equipment. The versatility and weight allow slew drives to act as an immediate solution to rotary related issues.
* Open housing models are usually lighter that enclosed housing models due to less housing material
Slewing products can be found in many applications including construction equipment, renewable energy solar trackers and wind turbines, turntables and welding positioners, packing and packaging equipment, and assembly lines. While slewing rings are most commonly used to generate slew rotation, slew drive technology capitalizes on the capacity of its internal slewing ring while introducing a built-in driving force through the worm gear. Speed and reduction ratios are better controlled through the worm wheel design as opposed to a standard slew ring and pinion. Slew drives allow for considerable space saving in the perpendicular planes as no additional gearboxes are required for speed reduction. In harsh environments, an enclosed housing slewing drive protects the internal components from debris and contamination through different sealing solutions.
Slewing drives are unique in the market because of their versatility. While a slewing drive comes standard in terms of size and outer dimensions. Customization and customer-specific requirements can be adhered to in the early design phases. The worm gear input can be modified to fit different motor input shaft dimensions as per application requirements. Cast iron or aluminum end caps are bolted down on both sides of the worm shaft to press the gear into position. This prevents axial play and provides better control over backlash. The standard orientation of a slew drive is horizontal allowing high axial loads and minimal radial loads. However, vertical orientation is widely spread across different applications. The number of bolts and their distribution on the slew drive surface plays a major role in the load capacity of a slew drive, but can be custom modified to fit/replace current models used by our customers.
SlewMaster provides its customers with a high-quality application-based slew drives product line. Sizes range from 7.5” (200mm) up to 20” (500mm) in ID. Standard hydraulic or electric motors are used to rotate the drive-through standard worm shaft inputs and can be assembled upon customer request depending on their application. To provide 360-degree rotation, hydraulic swivels are to be coupled with slew drives.
Our team of engineers is well equipped with the tools and technology necessary to work alongside our customers understanding their applications, design requirements, project scope, loads, and help identify the most suitable products. We are ready to provide technical support and slew drive recommendations based on application requirements.