At the top of the SF range sits the SF107 heavy duty gear reducer - a 107 mm centre-distance, two-stage helical-worm unit built for the toughest continuous duties. Its ductile-iron capable housing, large output shaft bearings and ground gearing make it the natural choice for existing S107 installations on sugar mills, wastewater thickeners, kilns and heavy material-handling drives.
Frame and Build
- Precision-machined cast-iron housing, HBS190-240, one-setup boring for shaft alignment
- 20CrMnTi gears carburised to HRC58~62; 42CrMo shafts tempered to HRC25~30
- Efficiency 94%~96%; noise 60~68 dB; vibration ≤20 μm; backlash ≤20 arcmin
- Lubrication: GB L-CKC220~460 or Shell Omala 220~460; NAK oil seals standard
- Mounting: foot, flange or torque arm; M1-M6 positions; solid or hollow output
Complete Specification
| Housing material | Cast iron/Ductile iron |
| Housing hardness | HBS190-240 |
| Gear material | 20CrMnTi alloy steel |
| Surface hardness of gears | HRC58~62 |
| Gear core hardness | HRC33~40 |
| Input / Output shaft material | 42CrMo alloy steel |
| Input / Output shaft hardness | HRC25~30 |
| Machining precision of gears | precision grinding, grade 6~5 (ISO 1328) |
| Lubricating oil | GB L-CKC220~460 / Shell Omala 220~460 |
| Heat treatment | tempering, cementit-ing, quenching, etc. |
| Efficiency | 94%~96% (depends on the transmission stage) |
| Noise (max) | 60~ 68dB |
| Temp. rise (max) | 40°C |
| Temp. rise (oil) (max) | 5 0°C |
| Vibration | ≤20μm |
| Backlash | ≤20Arcmin |
| Brand of bearings | HRB/LYC/ZWZ/C&U (SKF, FAG, INA, NSK optional) |
| Brand of oil seal | NAK -- Taiwan or other brands requested |
Proven in service across these industries:
- Building and construction machinery
- Conveyors, mixers, agitators and hoists
- Chemical and environmental protection plants
- Wood, forest and recycling equipment
- Metal processing lines
Ordering from WGT
Send the driven-machine data - torque, ratio, duty cycle, ambient temperature - and WGT engineers confirm the SF107 selection and quote within one working day. Units ship in reinforced wooden crates via NINGBO or SHANGHAI with full test documentation. One-year warranty, worldwide spare-part support and OEM batch pricing are all available from the factory.
Common Models in the SF Series
| Model | Centre distance | Output | Typical duty |
|---|
| SF37 | 37 mm | solid shaft, foot | small conveyors, dosing |
| SF47 | 47 mm | solid shaft, foot | packaging, dosing pumps |
| SF57 | 57 mm | solid shaft, foot | belt conveyors, stirrers |
| SF67 | 67 mm | solid shaft, foot | mixers, feeders |
| SF77 | 77 mm | solid shaft, foot | turntables, elevators |
| SF87 | 87 mm | solid shaft, foot | screw conveyors, washers |
| SF97 | 97 mm | solid shaft, foot | thickeners, kilns |
| SF107 | 107 mm | solid shaft, foot | heavy material handling |
The table below lists the eight foot-mounted frames;
Naming makes selection easy: S = solid shaft, SA = hollow shaft, SAF = hollow shaft with flange, SAZ = torque-arm version - all sharing the same gear set and centre distance as the SF foot model.
Application Cases
Automatic car-wash system
A car-wash equipment builder fits SA57 hollow-shaft reducers to its conveyor chains. The compact frame hides inside the wash tunnel, and FKM seal options handle the constant moisture.
Dust-extraction fan bank
An environmental-equipment plant uses SF47 reducers on rotary valve feeders of its dust-extraction systems. Compact size, quiet running and food-grade oil options made the approval easy.
![industrial gearbox applications - conveyor mixer crusher wastewater]()
Selection Example: Heavy belt feeder
Take a 15 kW, 1440 rpm motor on a apron feeder needing 18 rpm. The ratio follows directly: 1440 / 18 = 80, i=80. In this case the 107 mm frame and 42CrMo shafts carry the high starting torque. The same three numbers - motor speed, target output speed, required torque - are all you need; our engineers (or the online selector below) cross-check the service factor for your duty cycle.
![how to size a gear reducer in 4 steps - gearbox selection flow]()
Get Your Drawing and Quotation within 24 Hours
One minute, one model. Skip the back-and-forth: configure your drive in the WGT Motor & Gearbox Online Selection System and send us the result for a same-day quotation.
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 reducer for woodworking machine? Tell us the duty point and we will confirm the model in writing.
Frequently Asked Questions
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.
How do I calculate the ratio I need?
Divide motor speed by the target output speed (i = n1/n2), then check the required torque against the rating table with your service factor. The online selector below does this automatically.
