STM RMI 28 100:1 Worm Gearbox – 14mm Hollow Bore

This STM RMI 28 100:1 worm gearbox is a compact right-angle reducer with a 14mm hollow bore output, built for slow-speed drives, dosing systems, feeders, and machinery requiring very low output speed and higher torque. The RMI 28 frame uses a die-cast aluminium housing, modular IEC motor input options, and the proven STM wormgear design for quiet running and dependable industrial service.

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Gearbox Overview

The RMI 28 size is suited to applications needing a worm gearbox that is compact and lightweight for space-restricted light-duty machinery. With a 100:1 reduction ratio, this version is typically chosen where very high reduction for low output speed and higher torque demands are required, while keeping the simplicity and compactness of a single-stage STM worm gearbox.

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Why Choose This Configuration?

This exact model is best suited to buyers who specifically need an STM RMI 28 gearbox with a 100:1 reduction ratio and 14mm hollow bore. Compared with lower ratios it provides more speed reduction and torque multiplication, while compared with higher ratios it retains a more practical output speed for many industrial drives.

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Technical Details

Model: STM RMI 28
Gearbox type: Single-stage right-angle worm gearbox
Ratio: 100:1
Output bore: 14mm hollow bore
Housing material: Die-cast aluminium
Indicative gearbox weight: 1.4kg
Mounting positions: M1, M2, M3, M4, M5, M6
Ordering note: For sizes 28 to 70, no mounting-position specification is required in the order and units are supplied with plugs arranged for M1 as standard
Lubrication: Factory-filled lubricant; sizes 28 to 70 use the standard sealed arrangement without breather-plug requirement
Construction features: Die-cast aluminium housing with STM involute ZI wormgear profile for efficiency and quiet running

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Internal Links & Compatible Options

Same gearbox size, different ratios: explore the closest STM RMI 28 ratio options.

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

More STM gearboxes: Browse all STM RMI 28 gearboxes Browse all STM worm 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 input speed by a factor of 100, increasing available output torque while lowering output speed for controlled mechanical drive.

What is the STM RMI 28 gearbox commonly used for?

The STM RMI 28 is commonly used on conveyors, packaging machinery, feeders, automation equipment, and general industrial systems that need compact right-angle power transmission.

Is this gearbox supplied with a 14mm hollow bore?

Yes, this version is configured with a 14mm hollow bore output to suit compatible driven shafts and coupling arrangements.

What mounting positions can this gearbox be used in?

STM RMI units support M1, M2, M3, M4, M5, and M6 mounting positions. On smaller sizes such as this range, the gearbox is supplied arranged for M1 unless a different arrangement is specified where relevant.

What housing material is used on this STM RMI gearbox?

For the RMI 28 size in this range, the housing is die-cast aluminium, giving a good balance of strength, weight, and corrosion resistance for industrial use.