The M3RVSF70 vertical bevel helical gear unit extends the upright right-angle range into the 70 frame, where flange geometry and bearing seats grow enough to serve process shafts that a smaller build would have to overhang. A lapped spiral bevel pair accepts the motor from the side at the top of the stack; two ground helical stages hand torque down to a solid keyed output shaft under the housing. The arrangement keeps the deck clear, moves the electric motor to where a fitter can reach it, and holds the output axis rigidly in one casting rather than a chain of pedestals.
Where the 70 Build Starts to Pay
Frame selection is rarely a matter of nominal torque alone. On vertical duties three quantities accumulate: the bending moment of whatever hangs on the output, the steady running torque, and the axial push that a loaded shaft sends back up into the housing. The 70 build is dimensioned for the point where a single step-up in any one of them would leave a smaller frame running hot with a diminished bearing life. Specifying it at enquiry means the headplate is drilled once, the grout is poured once and the lifting plan is written for one weight - rather than a second visit after the first unit starts to run warm.
There is also the cost of confusion on site. When several vessels on one line share a frame, oil grades, seal kits and bolting torque all collapse into a single stores line. A plant that standardises on one build saves more in a year of stop-starts than it loses in first cost.
Decoding the Designation
| M | Three-stage industrial gear unit family |
| R | Spiral bevel input stage at a right angle to the output |
| V | Vertical output axis aimed down into the process |
| S | Solid keyed shaft; H in this slot marks a bored shaft |
| F | Foot and flange fixing to a headplate or steel support |
| 70 | Frame size in the upright range |
Each letter resolves to a machined feature: flange bolt circle, shaft diameter and keyway, seal bore, breather position, foot pattern. Two units sharing a ratio but differing in frame are different castings, and the coupling that fits one will not fit the other. That is why an order placed on ratio alone is a frequent source of return freight.
Lubrication With No Horizontal Reference
Upright housings need their own oil logic. The bottom bearing sits in the sump, the upper ones rely on splash thrown by rotating parts, and the breather has to sit where vapour escapes rather than where condensate collects. The dipstick or sight glass reads correctly only with the unit level and stopped; checking while the shaft turns is the standard route to overfilling, and overfilling drives oil up the top seal and onto the deck. Follow the plate for grade and the sheet for quantity, and log both when the unit is commissioned - later arguments about warranty tend to hinge on those two numbers.
Service profiles this build is regularly chosen for: Rake drives on grit removal channels at municipal works Vertical pump columns in steel mill scale pits Impeller agitators in latex and rubber compound tanks Slurry lift units on tailings pond reclaim lines Clarifier drives at paper mill white water loops Vertical screw feeders into lime silos Dosing tank mixers in water treatment plants Submerged pumps in shipyard dry dock sumps
Mounting and First Rotation
A vertical unit is assembled, run on a test stand in its working posture and shipped oil filled in a braced crate. The first look on site should match the drawing without shimming or rework. On the headplate, flatness and squareness decide seal life: any tilt passes straight through the shaft into the lip. Tighten in the sequence stamped on the flange, fit the breather vertically, then let the unit idle unloaded for several minutes before applying load. That idle pass exposes coupling run-out, a blocked breather and reversed rotation while the vessel is still empty.
Data to Send With the Enquiry
Output torque or motor rating, output speed, overhung load, direction of rotation, mounting posture, medium, ambient and daily hours are enough to size the frame and ratio in one exchange. Clear photographs of the existing installation and its nameplate remove the rest of the ambiguity faster than a written questionnaire.
Questions We Hear Most Often
How do I match the gear unit to my existing foundation?
Send the nameplate or the outline drawing of the unit being replaced. Frame dimensions follow the common industry dimension ladder, so foot holes, shaft heights and flange bolt circles normally match without redrilling foundations.
What ratio range does an industrial gear unit cover?
The range spans from low single-digit reductions to very high ratios by combining stage counts: two-stage builds for the lower band and up to five-stage builds for the highest reductions, with intermediate ratios available between catalogue steps on request.
Which lubrication system does the unit use?
Small and medium frames run on splash lubrication with mineral or synthetic oil. Larger frames or high ambient temperatures can be ordered with forced-feed circulation and cooling coils; the lubricant grade is stated on the nameplate and in the manual.
Choosing the Right Frame Size
| 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 |
One family, two layouts. Choose P for a coaxial-in / parallel-out drive train, R when the motor must turn 90 degrees; then pick the shaft type and mounting style that the machine interface needs.
Selection Example: Typical duty point
A quick worked example using this frame: Motor speed divided by the target output speed gives the ratio, rounded to the nearest available step, and the required torque with the service factor then fixes the frame size. It always comes down to those three figures. Send them over and we confirm the frame, ratio and service factor in writing.
![online gearbox selection system workflow]()
Selection workflow used by our engineers for every quotation.
Real-World Duty Points
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.
![right angle gearbox duty points overview]()
An overview of the duty points this series is built for.
Torque Margin Checked Before Every Quotation
No catalogue guessing. Use the WGT Motor & Gearbox Online Selection System to turn your motor data into a model number, and we will quote that exact unit within the day.
Every quotation includes the calculated service factor and the resulting torque margin, so the unit you buy covers the real duty - including starts, jams and reversals - not just the average load. Looking for a gearbox for mixer and agitator? Tell us the duty point and we will confirm the model in writing.
