The M3RVHF90 vertical hollow shaft gearbox is the large bored-output option of the upright range: the process shaft rises straight through the gear unit, and the drive hangs on the column instead of the column hanging on the drive. A lapped bevel pair at the input places the motor alongside the vessel at working height, and two helical stages reduce speed before torque reaches the bore. For tank, basin and sump duties it removes the coupling, the spacer and the alignment shift from the installation entirely.
What a Bored Output Buys at This Size
With a solid shaft plus coupling, every bending moment from a long column passes through a bolted joint that must be realigned after each service. The bored output eliminates that joint: the shaft is keyed or clamped by a shrink disc inside the housing bore, and the gear unit bearings carry the moment directly. At the 90 frame the bore accepts the heavy shaft sections used on industrial thickeners, digester mixers and large circulation pumps without adapters.
The trade is precision. Bore diameter, tolerance, key dimensions or shrink-disc rating and end float all have to be quoted to the millimetre, which is why a mating shaft drawing belongs with the enquiry. A unit that is correct in ratio but loose on bore cannot be recovered on site.
Reading the Designation
| M | Industrial multi-stage gear unit family |
| R | Right-angle input through a ground bevel set |
| V | Vertical housing, output at the underside |
| H | Hollow output, machined bore through the housing |
| F | Foot pads and flange face for headplate mounting |
| 90 | Frame size, largest of the stock upright builds |
Each letter converts into a dimension that belongs on the purchase confirmation: bore and fit, keyway or shrink-disc grade, seal material, flange drilling, breather position. Quoting the duty and the shaft drawing together is what produces a unit that bolts on without rework.
The Lower Seal Is a Consumable - Design for It
On a bored vertical unit the output seal sits directly beneath the process medium, and it is the one part scheduled for periodic attention. Cold water is the friendly case; brine, abrasive slurry, hot oil, solvent vapour and vacuum service each push the choice toward a different seal grade, and that choice is made at order stage, not in the stores.
The lower bearing shares the same environment and takes the shaft moment, so its life depends on whether the far end of the column is guided by a steady bearing and how the vessel floor is aligned. Declaring those details up front lets the factory set internal clearances to the real duty instead of to a guess.
Machine groups this unit is specified into: Final clarifier bridges at works treating combined flow Chest agitators feeding the machine section of paper mills Vertical propeller pumps lifting water to treatment stages Anaerobic digester mixing with tall centre columns Sedimentation basin scraper drives in alumina plants Brine circulation stirrers in chlor-alkali cells Foam breaking stirrers in fermentation vessels Settling cone drives in mineral processing thickeners
Installation on a Working Vessel
Measure the headplate before the order: bolt circle, hole pattern, face flatness and any pedestal height all belong on the drawing. On site, clean the face, check it with a straight edge across the full circle, and set the unit down without rocking it onto high spots. Raise the process shaft through the bore to the marked insertion depth, set end float to the drawing so thrust loads share as designed, then close the key or shrink disc to the recorded torque.
Fit the breather upright, fill to the plate quantity and read the level at rest. Hand-rotate the train once - a single binding point means the column is running out - then run unloaded briefly before applying process load. Record oil temperature and any seal weep at the end of the first shift; those two numbers become the reference for every later inspection.
Documentation and Repeat Supply
Every unit leaves with a dimensional drawing that fixes bore, flange and shaft data for the vessel file, and a nameplate that repeats frame, ratio and build. Kept alongside the vessel record, that pair lets a works order for an identical spare be raised from a photograph of the plate years later. For plants running several identical basins, one drawing plus one seal kit part number is usually the difference between a one-day changeover and a two-week stop.
Full Frame Range of the M3 Series
| 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 |
Every frame in the table can be ordered with alternative shaft and mounting styles. If you are matching an existing installation, send the nameplate details and we confirm the equivalent frame in writing.
Installation Snapshots
Airport baggage conveyor
An airport baggage-handling integrator uses reducers on check-in conveyors. Thousands of start-stop cycles a day are absorbed without overheating, and the low noise level matters in a public terminal.
Quarry primary crusher
A quarry operator fits industrial gear units on its primary jaw crusher feeders. The shock of rock dumped straight from the haul truck is covered by the service factor, and the cast-iron housing shrugs off years of dust and vibration.
Selection Example: Typical duty point
Work through the numbers for 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. Use the same method for any frame in the series, then confirm the service factor with us - it is the one number buyers most often get wrong.
![speed reducer selection process diagram]()
The selection path we follow when checking your enquiry.
Technical Q&A
Can this unit mount on my existing installation without redesign?
Yes - the series is manufactured to the same centre distances, shafts and flange dimensions of the common industry frames, so couplings, guards and foundations stay untouched.
Which lubricating oil should be used?
GB L-CKC220~460 or Shell Omala 220~460 as supplied. Under normal duty the housing is lubricated for life; in hot or continuous-duty environments an oil change after the first 400 hours and then every 4000 hours is recommended.
![speed reducer use cases across sectors]()
Typical installation environments for this gearbox family.
Get the Selection Checked - Free of Charge
Already picked a model? One screen in the WGT Motor & Gearbox Online Selection System is usually enough to pin down the frame size; we confirm the service factor afterwards.
Send us your calculated model and duty point. We cross-check the ratio, torque and service factor independently and confirm or flag the difference - a free second pair of engineer eyes. Looking for a reducer for woodworking machine? Tell us the duty point and we will confirm the model in writing.
