Worm Gear Overview

At Superior Gearbox Company, we’ve manufactured high-quality gear drives for power transmission systems for over 45 years. One of our core product offerings is low input speed worm gear reducers.

To achieve greater torque from a transmission requires a reduction of speed.  Speed reduction is the primary function of the Variodrive worm gear speed reducer series.  A worm gear speed reducer consists of a worm pinion input and output worm gear oriented for perpendicular output, which produces a higher torque value in relation to the applied reduction ratio.  The small diameter of the output gear allows the Variodrive to be used in applications where space is limited. In addition to decreased space and greater simplicity, our Variodrive series was designed to be directly interchangeable with most industry standard NRV & NMRV worm gear reducer solutions.

How Does a Worm Gear Reducer Work?

A worm pinion is a screw used to input power to the assembly. When coupled with a standard spur gear fitted with slightly angled teeth in a perpendicular alignment, known as a worm gear or worm wheel, the pairing becomes a worm gear reducer. As power from an engine or motor turns the worm pinion, its spirals push the teeth on the worm wheel, causing it to turn in accordance with the designed reduction ratio as it applies load to its drive shaft.

Higher reduction ratios may be achieved by increasing the circumference of the worm gear, or by increasing the number of threads on the worm pinion. Accomplishing the same reduction using conventional gear sets requires multiple reductions, which take up more space. Increasing the number of parts raising costs and adding to the risk of component failure.

Worm gear speed reducers provide efficient, space-saving solutions for speed reduction and increased torque when compared with bulkier, higher-maintenance conventional gearsets. Superior Gearbox’s Variodrive series is designed to overcome common speed reduction challenges with greater dependability and better performance, and extends to meet the needs of markets that require very high sanitary and hygienic design solutions with our Cleandrive Series.

Variodrive & Cleandrive Images

  • Variodrive Series

    In addition to decreased space and greater simplicity, a Variodrive includes a variety of features and benefits designed to provide greater efficiency in speed reduction and increased torque.  Our Variodrive series provides an advanced worm gear reduction solution for a variety of industries.  These units are designed with both efficiency and flexibility in mind.  Both the BMQ and B models can be used with a wide range of power ratings and reduction ratios, in addition to being directly interchangeable with industry-standard NMRV and NRV models.

    Benefits of a Variodrive solution: 

    • Heat dissipation. The ribbed aluminum design of the Variodrive provides improved heat dissipation, allowing for higher thermal resistance and reduced internal pressure buildup.
    • Design improvements. The typical bushing style reducers are replaced with two bearings along the input shaft, offering improved leak prevention and mounting flexibility.
    • Flange options. Standard NEMA motor flange or IEC motor flange configurations are available.
    • O-rings. The use of O-rings on the input flange and output cover, in contrast to typical paper gaskets, provides a more effective seal and prevent leakage.
    • Bore design. The hollow output bore design with optional plug-in shafts is standard on Variodrive, contributing to lowered inventory levels and improved profitability.
    • No ventilation. Variodrive does not require a breather plug or any form of ventilation because of its superior heat dissipation design. This feature allows lifelong sealing, mitigating the risk of outside contaminants.
    • Ratios from 100:1 in a single reduction stage and 10,000:1 in a double reduction unit are available.
    • Corrosion-resistant. The aluminum housing and protective coating mitigate the risk of corrosion.
    • Interchangeable. Both the BMQ and B models are designed to be directly interchangeable with most NMRV and NRV industry standard models.

  • Cleandrive Series

    Cleandrive units adhere to generally accepted principles of sanitary and hygienic design. These units enhance the functionality of equipment and facilities while reducing the potential threat of product cross contamination. The Superior Gearbox Cleandrive Series is suited for applications operating in corrosive environments that require a high level of sanitation while preventing adulteration.

    Benefits of a Cleandrive solution: 

    • Stainless Steel housings, shafts and hardware.
    • Food grade synthetic lubricant.
    • Smooth surfaces to comply with stringent requirements for the food processing industry
    • Easy to clean: All products within the Superior Gearbox Cleandrive product lines incorporate sound elements of design that allow for easier access to facilitate cleaning.
    • Cleandrive units are designed to help provide a safe production environment for our customers.
    • Designed to be directly interchangeable with most industry-standard NMRV applications requiring a high standard of hygiene such as the food industry.

Low Input Speed Worm Gear Reducers

Superior Gear also provides a variety of low-input speed worm gear reducers to accommodate a wide range of circumstances. Our models include:

V210 Series

  • Ratios: 5:1, 10:1, 20:1 (left hand or right hand)
  • Input: 1″ or hydraulic motor
  • Output: 1.25″
  • Weight (including lubricant): 25 lbs.

W260 Series

  • Ratios: 12.5:1, 25:1, 50:1 (left hand or right hand)
  • Input: 1″ or hydraulic motor
  • Output: 2″ solid (1.5″ hollow bore on request)
  • Weight (including lubricant): 55 lbs.

I210 Series

  • Ratios: 20:1 (left hand or right hand)
  • Input: 1″ or hydraulic motor
  • Output: 1.25″
  • Weight (including lubricant): 35 lbs.

I260 Series Low Input Speed Worm Gear Reducers

I260 Series

  • Ratios: 25:1, 50:1 (left hand or right hand)
  • Input: 1″ or hydraulic motor
  • Output: 2″ solid or hollow bore
  • Weight (including lubricant): 85 lbs.

I280 Series

  • Ratios: 50:1 (left hand or right hand)
  • Input: 1.25″ or hydraulic motor
  • Output: 2″ hollow bore shaft
  • Weight (including lubricant): 110 lbs.

  • Request a Quotation

Ways to Request a Quote

Complete this online quote form by providing your contact information, detailed specs, and uploading your photos.

Email your photos and specs directly to: sales@superiorgearbox.com.

Call us at 1-800-346-5745 to discuss your manufacturing needs. You will always talk to a real person!



Seal and bearing kits are available at superiorgearboxdirect.com.

Service Manuals can be downloaded here.