Buyers who need a mid-size right angle gearbox that does not give away efficiency will find the K47 a proven answer. The unit uses the same 47 mm centre-distance family, so existing couplings, guards and foundations stay untouched. Because both stages are toothed - helical in, bevel out - the K47 speed reducer runs cooler and quieter than any comparable worm unit at the same ratio.
Why the K47 Holds Its Efficiency
Two toothed stages mean rolling contact rather than sliding contact, so losses stay low whatever the ratio. The housing is a single casting in cast iron or ductile iron, hardness HBS190-240, bored in one setup; gears are 20CrMnTi, case-carburised to HRC58~62 over a tough HRC33~40 core and finished by precision grinding to grade 6~5. Shafts are 42CrMo, quenched and tempered to HRC25~30, and bearings are supplied by HRB, LYC, ZWZ or C&U, with SKF, FAG, INA or NSK available on request.
Specification Table
| 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 |
Typical duty points where this unit is specified:
- Conveyors, mixers, agitators and crushers
- Paper and light industry
- Harbour and shipping machinery
- Electric power plants
- Coal mining and bulk material handling
Quotation and Delivery
Every K47 ships factory-tested, with noise, temperature rise and backlash recorded before packing in a standard export wooden crate. Send your ratio, output torque and mounting style - our engineers confirm the selection the same day and quote EXW or CIF accordingly. Urgent units for a breakdown can be air-freighted after payment, and spare seal and bearing kits are available from stock.
The K Series at a Glance
| Model | Centre distance | Output | Typical duty |
|---|
| K47 | 47 mm | solid shaft, foot | packaging, agitators |
| K37 | 37 mm | solid shaft, foot | small conveyors, hoists |
| K57 | 57 mm | solid shaft, foot | belt conveyors, mixers |
| K67 | 67 mm | solid shaft, foot | mixers, feeders, hoists |
| K77 | 77 mm | solid shaft, foot | turntables, elevators |
| K87 | 87 mm | solid shaft, foot | screw conveyors, washers |
| K97 | 97 mm | solid shaft, foot | thickeners, heavy conveyors |
| K107 | 107 mm | solid shaft, foot | heavy material handling |
| K157 | 157 mm | solid shaft, foot | mill drives, large hoists |
| K167 | 167 mm | solid shaft, foot | heaviest right-angle drives |
All frames share one helical-bevel gear set family, so a change of frame size rarely means a change of mounting: K is the foot-mounted version with a solid shaft, KA has a hollow output, KF adds a flange and KAF combines the flange with a hollow shaft.
Selection Example: Packing-line turntable
Take a 2.2 kW motor at 1440 rpm turning a packing turntable at 36 rpm. The ratio follows directly: 1440 / 36 = 40, i=40. In this case a 90 degree output lets the motor sit parallel to the machine frame. That single division gives the catalogue ratio; the service factor for your duty class is then applied to the torque, and the frame size follows.
![how to size a helical-bevel gearbox in four steps]()
Sizing flow: motor speed, target output speed, torque, service factor.
Where This Series Works in Practice
Automatic car-wash line
A car-wash equipment builder fits hollow-shaft reducers to its conveyor chains. The compact frame hides inside the wash tunnel, and FKM seal options handle the constant moisture.
Textile dyeing drums
A dyeing machine maker uses speed reducers on its fabric-turning drums. Low vibration (under 20 microns) prevents streaks in the fabric, and the 94-96% efficiency keeps the heat load down in a warm workshop.
Technical Questions, Answered
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.
Can the reducer be supplied with a brake motor or an IEC motor flange?
Yes. We supply the reducer as a bare unit with an IEC standard input flange, and you can bolt on any IEC or NEMA motor - including a brake motor. The flange dimensions follow the common IEC pattern, so existing motors drop straight on.
![helical-bevel gear reducer application fields]()
Common application areas for right-angle helical-bevel drives.
Size It, Quote It, Ship It
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.
Give us the driven machine, the required output speed and the daily running hours, and we return a confirmed model number with torque margin and a firm price - no obligation, no charge for the selection work. Looking for a gear reducer for screw conveyor? Tell us the duty point and we will confirm the model in writing.
