The MC2PLSF07 heavy duty parallel shaft gearbox is the largest of the compact two-stage frames, and it is bought for the duties that break smaller units: a primary crusher discharging onto a belt that starts loaded, a boom conveyor on a bulk terminal that reverses under load, a raw mill feed that never really stops. Same layout as its neighbours - parallel stages in one plane, footed base, motor alongside - but the casting, shafts and bearings are sized for punishment rather than for nominal torque.
Where the 07 Frame Belongs on a Bulk Plant
Three locations keep coming back in enquiries. The first is downstream of a primary crusher, where the belt sees rock at uncontrolled lump size and the drive absorbs shocks that no steady-state calculation predicts. The second is a terminal conveyor train, where a loaded boom has to stop and restart without emptying the belt first. The third is the wet end of a minerals plant, where sticky material builds on the belt and the effective load creeps up through the shift.
In all three, the 07 is not chosen because the running torque demands it. It is chosen because the starting torque, the shock content and the consequence of a stoppage together justify a frame with room to spare. Plants that have already paid for one unplanned shutdown tend to make that argument for themselves.
Reading MC2PLSF07 Without the Catalogue
| MC2 | Compact two-stage family with parallel shafts in a single plane |
| P | Shafts run parallel, so the drive stays low and long rather than tall |
| L | Cast case with integrated foot pads and a generous oil sump |
| S | Solid output shaft, keyed for a coupling hub or a pulley |
| F | Foot mounted, horizontal; the base is drilled for through bolts |
| 07 | Top frame of the range, with the widest centre distance and heaviest shaft set |
Nothing in that string tells you the ratio, which is why the full order code always carries the ratio and mounting position as separate fields. Quote both when asking for a drawing, or the reply will be a generic dimensional sheet that does not match the mounting you have.
Checking a Quotation Against the Driven Machine
When an offer arrives, three checks settle most of it. First, the ratio: motor speed divided by the required output speed, rounded to an available step, and the resulting output speed compared with what the process actually needs. Second, the service factor: it should reflect the starting condition, not only the running load, and a supplier who does not ask about starting should be asked why. Third, the shaft and bore detail, because a gearbox that fits the frame but not the coupling becomes a machining job on site.
Thermal capacity is the fourth, quieter check. A unit can pass the torque sum and still run hot if the ambient is high or the sump sits in still air. On an 07 frame there is usually margin, but the question is worth putting in writing for a drive installed inside a closed gallery.
Duties This Frame Was Made For
Drive points where a shaft-mounted bevel-helical unit is the natural answer:
- Primary crusher discharge conveyors in hard-rock quarries
- Stockyard and ship-loader boom conveyor drives at bulk terminals
- Raw mill feed and reject conveyor drives in cement works
- Sinter and pellet handling conveyors in iron and steel plants
- Heavy duty screw conveyors moving wet ore and tailings
- Wagon loading and unloading conveyor drives at rail sidings
If a duty on that list looks like yours, the next step is simply to confirm the numbers rather than to debate frame size.
Installing a Heavier Unit with the Crew You Have
An 07 frame is heavy enough that lifting needs a plan: certified slings on the cast lugs, a spreader if the angle is wide, and nobody under the load while it swings. Set it down on prepared pads, not on packing timber, and check the frame with a level before the bolts are torqued. Shims go in full packs under each foot so the case is not stressed into alignment.
Alignment then follows the usual discipline: rough centring by straight edge, fine work with a dial gauge or laser, and a hot check after the drive has run under load. On a crusher discharge duty, re-check after the first week - the belt tension settles and pulls the pulley, and the coupling tells you about it before the bearing does.
Watching Oil and Bearings on a Larger Sump
A bigger case holds more oil, which is both an advantage and a trap. The advantage is thermal stability and longer drain intervals; the trap is that a slow leak takes longer to show on the sight glass, and by the time the level drops the top gearset may have been running on splash alone. Mark the cold level on the glass with a paint pen, and check against the mark rather than against memory.
Bearing condition is best followed by temperature and sound together. A monthly reading with a contact thermometer at the same point on each bearing housing builds a trend; a rise of a few degrees over several weeks is the earliest usable warning. Vibration readings, where the site has the instrument, confirm it. Neither method needs the unit to be opened.
Procurement Details That Shorten Delivery
For a quotation that can be turned into an order without a second round, send the motor rating and speed, the required output speed or ratio, the mounting position, the driven machine and its starting condition, the ambient and altitude, and any shaft or bore dimension that has to match existing hardware. Paint colour, nameplate language and inspection requirements belong in the same message. With those on the table the frame, ratio and options are fixed in one exchange, and the delivery slot is confirmed against a specification rather than an assumption.
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
Grain terminal elevators
A grain terminal powers its bucket elevators with gear reducers. The anti-run-back option holds the loaded buckets during power cuts, and standard interface dimensions meant the old foundations were reused as they were.
Pallet lift in a warehouse
A logistics integrator selected units for pallet lifts. The hollow output bore carries the lift screw directly, and one year of three-shift operation has passed without a single seal replacement.
Selection Example: Primary crusher discharge conveyor restart
Take a 1485 rpm four-pole motor starting a crusher discharge belt that is still loaded, at a pulley speed of 11 rpm. The ratio follows directly: 1485 / 11 = 135, which needs the deepest two-stage band and a breakaway torque figure taken from the belt maker rather than from running load. In this case the 07 frame and its heavy shaft set are chosen for that breakaway moment, so the unit is not living at its limit every time the belt restarts. 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
What is a service factor and which value should I use?
The service factor multiplies your required torque to cover shock and duty class: around 1.0 for uniform conveyors, 1.25 for moderate shocks and 1.5 or higher for crushers, shredders and reversing drives. Tell us the driven machine and we apply the correct value before quoting.
Can the gear unit hold a load on an inclined conveyor?
For inclined belts a backstop prevents the loaded belt from driving the unit backwards when power is cut. Specify the incline angle when ordering so the backstop and the oil level are matched to the actual mounting position.
![speed reducer use cases across sectors]()
Typical installation environments for this gearbox family.
Sample Units Available for Performance Testing
Validating before you commit? 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.
Sample units can be supplied for bench or field testing so your team can confirm noise, temperature rise and backlash before a production order. Tell us the test conditions and we will prepare the documentation. Looking for a speed reducer for bucket elevator? Tell us the duty point and we will confirm the model in writing.
