SITI MI70 40:1 Worm Gearbox – 28mm Hollow Bore

This SITI MI70 40:1 worm gearbox is a compact right-angle speed reducer designed for applications requiring balanced speed reduction and torque multiplication across general industrial machinery. With a 28mm hollow bore output and 80B5, 80B14, 90B5 & 90B14 IEC motor input options, it is a practical choice for OEM and replacement duties where smooth running, compact installation, and dependable industrial service are important.

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Gearbox Overview

This mid-range MI size gives a strong balance of compact dimensions, practical torque capacity, and straightforward machine integration. The 40:1 ratio is a practical middle-ground option where a balanced mix of output speed reduction and torque increase is required.

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Why Choose This Configuration?

A 40:1 worm gearbox is typically selected for general-purpose speed reduction duties where users need a balanced output speed, useful torque gain, and compact IEC motor compatibility. In practical terms, this configuration is well suited to conveyors, processing equipment, automation systems, and general machinery needing balanced speed reduction and torque, while still keeping the compact MI-series format and flexible IEC motor input compatibility.

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Technical Details

Gearbox size: MI70
Gear ratio: 40:1
Output type: Hollow bore
Output bore: 28mm
Motor input options: 80B5, 80B14, 90B5 & 90B14
Input mounting: IEC motor input options as listed on the product page
Lubrication: Pre-lubricated with synthetic oil ISO VG 320 PAG
Operating temperature: -10°C to +30°C with synthetic oil
Mounting position: Must match the ordered mounting position / installation arrangement
Construction: Industrial right-angle worm gearbox
Approximate gearbox weight: 10kg

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Internal Links & Compatible Options

Same gearbox size, different ratios: compare nearby reduction options for the SITI MI70.

Same ratio, different gearbox sizes: explore nearby sizes offering a 40:1 ratio.

More SITI gearboxes: Browse all SITI gearboxes Browse all worm gearboxes

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

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Frequently Asked Questions

What does a 40:1 worm gearbox do?

A 40:1 worm gearbox reduces the input speed by a factor of 40, increasing torque output while lowering shaft speed for smoother and more controlled drive performance.

What is this SITI MI70 gearbox commonly used for?

This gearbox is commonly used on conveyors, packaging machines, automation systems, feeders, small processing equipment, and general industrial machinery where a compact right-angle drive is required.

Is this gearbox pre-lubricated?

Yes. SITI MI gearboxes are supplied pre-lubricated with synthetic ISO VG 320 PAG oil for standard service conditions.

Can this gearbox be used in different mounting positions?

SITI gearboxes can be supplied for different mounting positions, but the unit should be installed in the ordered mounting arrangement so lubrication remains correct.

What should I check before replacing a SITI MI70 gearbox?

Check the gearbox size, ratio, output bore size, motor input option, and mounting arrangement before ordering a replacement unit.

What is the output bore on this gearbox?

This version is supplied with a 28mm hollow bore output.