The M3RSF50 bevel helical gearbox is the right-angle member of the M-series at the entry of the horizontal size ladder. A bevel input stage turns the drive 90 degrees, and two further helical stages bring the speed down on a solid foot-mounted output shaft. Where a parallel-shaft unit would force the motor to stand out along the conveyor line, this build tucks the motor to the side - often the only way to keep a drive point inside a narrow plant layout.
A Right-Angle Drive in the Smallest Horizontal Frame
Size 50 is the smallest horizontal frame of the industrial range, and in the R build it covers the drives that are modest in power but relentless in duty: inclined belt conveyors, classifiers, chippers and crane travel mechanisms. The horizontally split cast-iron housing, the case-hardened and ground gearing and the generous bearing spans are shared with every other frame in the family, so maintenance routines and spare-parts thinking carry over from the larger units already running in the plant.
How the R Build Differs from the P Build
| Gear arrangement | R adds a bevel input stage, turning the motor 90 degrees; P keeps all stages helical on parallel axes |
| Footprint | Right-angle input shortens the drive line along the machine axis - decisive in narrow corridors |
| Low-speed shaft | Solid steel in this build, keyed for a standard coupling; hollow variants use the H code |
| Mounting | Foot mounting to industry foundations; the T code swaps feet for a torque arm |
| Ratios | The bevel stage plus two helical stages cover the moderate band typical of conveyor and machine drives |
One caution worth stating plainly: the right-angle build trades a little efficiency for the 90-degree turn, because the bevel stage is a sliding-contact gear. For the duties listed here that trade is well understood and routinely accepted; for very high-power continuous service, plants often prefer the parallel-shaft build.
The machines this unit is routinely paired with:
- Inclined and swan-neck belt conveyors where the motor must turn 90 degrees
- Screw classifiers and rake drives in mineral processing
- Cooler and dryer drum drives in fertiliser plants
- Stationary concrete mixer and batching plant drives
- Scrap and wood chipper drives with shock-type load profiles
- Overhead crane long-travel mechanisms on wall consoles
Decoding the M3RSF50 Code
| M3 | M-series industrial gear unit with three gear stages |
| R | Bevel-helical right-angle layout (P would be the all-helical parallel build) |
| S | Solid low-speed shaft (H marks a hollow shaft) |
| F | Foot mounting (T marks torque-arm mounting) |
| 50 | Frame size, the entry point of the horizontal range 50 to 90 |
Drawings, Selection and Supply
WGT issues the M-series catalogue and the size 50 outline drawing as PDF downloads, so shaft height, foot pattern and the motor-side interface can be confirmed before ordering. Send the driven machine, the motor power and speed, the required output speed and the running pattern; the rated torque is checked, a written quotation follows, and every unit ships factory-tested in an export wooden crate with a one-year warranty.
How Customers Use This Unit
Pet-food extruder feeder
A pet-food plant chose reducers for the feeder screws ahead of its extruders. Steady torque at variable output speed keeps the kibble size consistent, and washdown sealing protects the unit during sanitation shifts.
Ceramic tile press feeder
A ceramic tile producer fitted reducers to press feeders. The dusty environment is handled by sealed housings, and the stable low-speed output stops the tile blanks shifting before pressing.
What Engineers Ask Us
What is the maximum overhung load on the output shaft?
The permissible overhung load depends on frame size, output speed and the distance from the shaft shoulder - all listed in the catalogue. If you drive a chain sprocket or V-belt pulley direct on the output shaft, send us the load and pitch diameter and we will confirm the limit.
Do you offer a version with an integrated gear motor?
We can supply the unit as a complete gear motor with an IEC motor bolted on and tested as one assembly. That saves you the alignment and coupling work, and the whole assembly carries the same one-year warranty.
Model Table: Frames, Shafts and Duty
| Model | Centre distance | Output | Typical duty |
|---|
| M3RSF50 | size 50 | solid shaft, foot, right-angle | inclined conveyors, elevators |
| 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 |
| 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 |
Larger size numbers mean higher torque capacity and larger shafts. Because interfaces follow the common industrial dimensions, a size-for-size change is the normal upgrade route for these industrial units.
Selection Example: Inclined belt conveyor drive
Take a 30 kW motor at 1465 rpm driving an inclined belt at 58 rpm. The ratio follows directly: 1465 / 58 = 25.3, so i=25 with the bevel stage providing the right-angle input. In this case the right-angle build turns the motor 90 degrees so the conveyor line keeps a straight footprint. Note that the ratio comes from speeds alone, while the frame size depends on torque and service factor - never size a unit on ratio only.
![industrial helical gearbox selection chart]()
A quick visual of the selection sequence for a industrial helical unit.
![M3 series gear reducer installation examples]()
Application coverage of the the M3 series.
Gearbox Selection Support from the Factory Floor
Talk to the people who build it. Prefer to check the figures yourself? The WGT Motor & Gearbox Online Selection System gives you the model, torque margin and ratio before you ask us.
Our technical team sits beside the assembly line, not in a call centre. Describe the application in your own words - we will tell you honestly whether this series is right, or point you to a better frame or a different series. Looking for a reducer for woodworking machine? Tell us the duty point and we will confirm the model in writing.
