Varvel FRS28 100:1 Worm Gearbox – 14mm Output Bore, IEC Motor Input Options

This Varvel FRS28 100:1 worm gearbox is a single-stage right-angle reducer designed for applications needing very low output speed and high torque multiplication. It features a 14mm hollow output bore, accepts multiple IEC motor inputs, and uses a modular Varvel design that allows straightforward integration into conveyors, packaging equipment, automation systems, and general industrial machinery. The FRS series is supplied with synthetic long-life oil, ISO VG 320, for dependable day-to-day service.

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Gearbox Overview

The FRS28 is part of the Varvel RS-RT single-stage worm gearbox range. FRS and FRT units share the same performance data and reduction ratios, while FRS uses the round-housing layout suited to a wide range of shaft-mounted, footed, and flanged arrangements. This 100:1 ratio is normally selected where very high reduction for slower output speed and higher torque output is needed without moving into a more complex multi-stage unit.

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Why Choose This Configuration?

This product is best suited to buyers who need a Varvel FRS28 gearbox with a 14mm hollow output bore and IEC motor inputs from 56B14 to 63B5. Compared with lower ratios, a 100:1 reduction delivers stronger speed reduction and higher torque multiplication at the output, while still retaining the compact footprint and modular motor mounting flexibility of the Varvel RS-RT range.

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Technical Details

Gearbox series: Varvel FRS single-stage worm gearbox
Gearbox size: FRS28
Reduction ratio: 100:1
Output bore: 14mm hollow bore
Motor input options: 56B14, 56B5, 63B14, 63B5
Housing material: Pressure die-cast aluminium housing
Output shaft style: Hollow output shaft as standard
Lubrication: Synthetic long-life oil, ISO VG 320
Oil quantity: Approx. 0.03 litres
Recommended ambient temperature: -15°C to +35°C
Oil seals: NBR as standard
Mounting positions: B3, B5, V5, B8, V6, B6, B7 and related catalogue variants depending on configuration
Approximate gearbox weight: 1.1kg
Protection grade: IP66 gearbox body only; IP20 with flanges and adapters
Maximum catalogue output torque range: Varvel RS-RT range up to 3020Nm

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Internal Links & Compatible Options

Same gearbox size, different ratios: explore nearby reduction options for the Varvel FRS28 worm gearbox.

Same ratio, different gearbox sizes: explore nearby sizes offering a 100:1 ratio.

More Varvel gearboxes: Browse all worm gearboxes Browse all gearboxes

Helpful calculators:
Gearbox Ratio & Speed Calculator |
Output Torque Calculator

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Frequently Asked Questions

What does a 100:1 worm gearbox do?

A 100:1 worm gearbox reduces the motor input speed by a factor of 100, lowering the output speed and increasing torque at the driven shaft.

What is the benefit of the FRS design?

The Varvel FRS design is part of the RS-RT modular worm gearbox range, allowing multiple motor adapters, feet, output flanges, and torque arm fittings to suit different machine layouts.

Is this gearbox supplied lubricated?

Yes. Varvel RS-RT gearboxes are supplied filled with synthetic long-life ISO VG 320 oil for lubrication-for-life service under the stated operating conditions.

What output shaft does this gearbox use?

This gearbox uses a 14mm hollow output bore as standard. Solid output shafts can be supplied separately for compatible arrangements.

What operating conditions are the standard catalogue ratings based on?

The standard selection data are intended for service factor SF1.0, meaning 8 running hours per day, uniform load, up to 6 start/stops per hour, and ambient temperature between 15°C and 35°C.

What housing material does this gearbox use?

For the RS-RT range, sizes up to 85 use pressure die-cast aluminium housings, while sizes from 110 upward use cast iron housings.