The M3RSF90 right angle industrial gear reducer is the top solid-shaft build of the right-angle family: size 90 housing, spiral-bevel input stage turning the motor through a right angle, and two helical stages closing the reduction on parallel axes. The solid keyed output hands torque to a conventional coupling, and the foot-mounted cast-iron housing anchors the whole drive to the foundation.
The Largest Solid-Shaft Right-Angle Frame
Size 90 is where the family stops scaling the horizontal band, and it is bought for the drive points that sit just below the very highest torque class: long overland conveyors, quarry apron feeders, clinker transport lines. The design keeps the virtues of the smaller frames - horizontally split housing, ground case-hardened gearing, one shared oil sump - while the shaft and bearing diameters grow to carry sustained overhung and torsional load. Efficiency stays high across the ratio band because no stage relies on sliding contact, which keeps motor sizing honest on drives that run three shifts.
Reading M3RSF90 from the Nameplate
| M3 | Industrial gear unit family, three geared stages |
| R | Bevel-helical right-angle input (P marks the all-parallel build) |
| S | Solid low-speed shaft with keyed coupling seat (H would open a hollow bore) |
| F | Foot-mounted reaction into the foundation (T would fit a torque arm) |
| 90 | Frame size 90, top of the horizontal range |
Because the notation is strictly compositional, a size 90 order can be re-lettered to a hollow output or a torque-arm build without touching the gear geometry, and the plant drawing office can quote interface dimensions from the same outline drawing family used across the whole band.
Drivetrain duties this frame answers to:
- Primary crusher feed and apron conveyors in quarries
- Long-distance overland conveyors with high installed power
- Cement plant clinker transport and drag chain lines
- Thickener and clarifier rake drives in mineral plants
- Dredge and shiploader slew and travel drives
- Sugar mill cane carrier and bagasse conveyors
Bulk Handling Duties at the Top of the Band
The solid-shaft choice at this frame size is typical of conveyors and feeders where the head pulley or drive drum runs in its own plummer blocks, so the gear unit and the machine meet through a coupling that can be inspected and re-aligned on schedule. Bevel-helical layouts are chosen on these same drives for layout freedom: motors sit outside the material flow, guards stay simple, and the drive train leaves the conveyor axis entirely. WGT reviews overhung load, service factor and starting duty against the installation drawing before a selection is confirmed.
Enquiry to Dispatch
The catalogue and size 90 outline drawing are supplied as PDF downloads for interface verification - shaft height, bolt pattern, coupling seat, motor flange. Provide the driven machine, motor power and speed, required output speed and the shift profile, and the rated-torque check completes the selection; a written quotation follows. Every unit is run at the factory, packed in an export wooden crate and covered by a one-year warranty.
Selection Example: Overland conveyor pulley drive
Take a 315 kW motor at 1490 rpm driving a conveyor drive pulley shaft at 9 rpm. The ratio follows directly: 1490 / 9 = 165.6, so the top three-stage ratios with a raised service factor cover the pulley torque. In this case the bevel input parks the motor clear of the belt line while the solid output couples to the independently bearing-mounted pulley shaft. Work through the same three steps - speed, output speed, torque - and the model number falls out; we verify it against the duty class before quoting.
![gear reducer ratio calculation steps]()
From duty point to model number - the same four steps every time.
Applications in Industry
Stacker-reclaimer travel drive
A bulk terminal drives the travel gear of a stacker-reclaimer with units. Long-travel duty with frequent direction changes is smoothed by the ground gearing, and backlash stays within 20 arcmin over the full rail length.
Automatic parking system
A parking equipment manufacturer uses reducers on its puzzle-type car stackers. The hollow shaft takes the drive axle directly, and the quiet 60-68 dB operation suits installations inside residential buildings.
![gear reducer industries served - WGT]()
Industry map: the sectors where the M3 series is most common.
Buyer Questions and Answers
Can the reducer be used outdoors or in a washdown area?
Standard paint and NAK seals suit sheltered outdoor duty. For washdown or coastal sites specify the heavy-duty coating, FKM seals and stainless fasteners; for humid rooms we recommend the breather and oil-check routine in the manual.
What if the ratio I need falls between two catalogue steps?
Choose the next available step and adjust the driven speed, or ask us for a special pair of gears. Trimming the driven machine is normally cheaper than ordering a special ratio, and a slightly higher ratio never hurts the drive.
M3 Series Model Overview
| Model | Centre distance | Output | Typical duty |
|---|
| M3PSF50 | size 50 | solid shaft, foot | conveyors, feeders |
| M3PSF60 | size 60 | solid shaft, foot | crushers, mixers |
| M3PSF70 | size 70 | solid shaft, foot | ball mills, shredders |
| M3PSF80 | size 80 | solid shaft, foot | kilns, heavy conveyors |
| M3PSF90 | size 90 | solid shaft, foot | mill and kiln drives |
| M3RSF50 | size 50 | solid shaft, foot, right-angle | inclined conveyors, elevators |
| M3RSF60 | size 60 | solid shaft, foot, right-angle | screw classifiers, feeders |
| M3RHF70 | size 70 | hollow shaft, foot, right-angle | agitators, drum drives |
| M3PHT80 | size 80 | hollow shaft, torque arm, parallel | shaft-mounted conveyors |
| M3RHT90 | size 90 | hollow shaft, torque arm, right-angle | heavy shaft-mounted drives |
The series is sized for continuous heavy duty rather than by motor power alone: the required torque with the service factor decides the frame, and the stage count (2 to 5) decides the ratio band.
Get Your Drawing and Quotation within 24 Hours
Ready to size your drive? Run your duty point through the WGT Motor & Gearbox Online Selection System first: it saves a round of emails and gets you to a firm price faster.
Or simply send your motor data (kW, speed, duty) and driven-machine details through the inquiry button - we reply with a completed datasheet, dimension drawing and factory price the same working day. Looking for a gear reducer for textile machinery? Tell us the duty point and we will confirm the model in writing.
