BG — worm gearboxes, square housing
Square worm gear reducers, sizes 025 to 150, ratios 7.5 to 100, up to 1 610 Nm.
The BG series is Bernati's main worm gearbox range. The square housing is die-cast aluminium up to size 090 and cast iron from 110 to 150, and can be fixed in any mounting position. Sizes up to 090 are lubricated for life with synthetic oil; sizes 110 to 150 use mineral oil and a simple maintenance plan.
Key characteristics
Conveyors, packaging lines, mixers, hoists and general machinery needing compact right-angle reduction.
- IEC input flange B5 / B14 for direct motor coupling (PAM 56 – 160) or solid input shaft
- Hollow output shaft; single or double solid output shaft, output flanges and torque arm as accessories
- Pre-stage (BGPC) and combined double-worm (BGC / BGSC) configurations for very low output speeds
- Epoxy finish RAL 9006
- Designed for input speeds up to 2 800 rpm
Available range
| Size | Ratio i | Max. output torque T₂ (Nm) | Input power P₁ (kW) | IEC motor flange (PAM) | Weight (kg) |
|---|---|---|---|---|---|
| BG 025 | 7.5 – 60 | 14 | 0.09 | 56 B14 | 0.7 |
| BG 030 | 7.5 – 80 | 22 | 0.09 – 0.25 | 56, 63 B5/B14 | 1.2 |
| BG 040 | 7.5 – 100 | 52 | 0.18 – 0.55 | 56, 63, 71 B5/B14 | 2.3 |
| BG 050 | 7.5 – 100 | 87 | 0.18 – 0.75 | 63, 71, 80 B5/B14 | 3.5 |
| BG 063 | 7.5 – 100 | 165 | 0.37 – 1.5 | 71, 80, 90 B5/B14 | 6.2 |
| BG 075 | 7.5 – 100 | 260 | 0.55 – 4.0 | 71, 80, 90, 100 B5/B14 | 9 |
| BG 090 | 7.5 – 100 | 478 | 0.75 – 4.0 | 80, 90, 100 B5/B14 | 13 |
| BG 110 | 7.5 – 100 | 764 | 1.1 – 7.5 | 90 – 132 B5/B14 | 35 |
| BG 130 | 7.5 – 100 | 1225 | 1.5 – 7.5 | 90 – 132 B5/B14 | 48 |
| BG 150 | 7.5 – 100 | 1610 | 3.0 – 15 | 100 – 160 B5 | 84 |
Technical specification
| Housing | Square, die-cast aluminium (025 – 090); cast iron (110 – 150) |
|---|---|
| Sizes | 025, 030, 040, 050, 063, 075, 090, 110, 130, 150 |
| Reduction ratios | 7.5 – 100 (025: 7.5 – 60; 030: 7.5 – 80) |
| Output torque | ≤ 1 610 Nm (BG 150) |
| Input power | 0.09 – 15 kW |
| Input | IEC motor flange B5 / B14 (PAM 56 – 160) or solid input shaft |
| Output | Hollow shaft; single or double solid output shaft as accessory |
| Finish | Epoxy paint RAL 9006 |
| Lubrication | 025 – 090 and pre-stages: synthetic, lubricated for life, universal mounting; 110 – 150: mineral oil, B3 fill, simple maintenance plan |
| Mounting | B3, B6, B7, B8, V5, V6 — square housing mounts in any position |
| Max. input speed | 2 800 rpm |
Mounting arrangements
B3, B6, B7, B8, V5, V6 — square housing mounts in any position
- B3Foot-mounted
- B6Foot, side
- B7Foot, side
- B8Foot, inverted
- V5Vertical, shaft down
- V6Vertical, shaft up
Configurations
| Code | Input | Sizes |
|---|---|---|
| BG | IEC input flange B5 / B14 | 025 – 150 |
| BGS | Single solid input shaft | 030 – 150 |
| BGB | IEC input flange and solid input shaft | 030 – 150 |
| BGSB | Double solid input shaft | 030 – 150 |
| BGPC | Integrated pre-stage with IEC flange | pre-stage 63 – 90 |
| BGC | Double worm (combined) with IEC flange | combined |
| BGSC | Double worm (combined) with solid input shaft | combined |
| BGL | With torque limiter (data on request) | — |
Technical downloads
3D / CAD models
3D models (STEP) and 2D drawings are available for every BG variant on our distributor's product pages. Downloading requires a free customer account.
Typical applications
General machinery
Production machines and assembly lines running for long periods: three-phase BMT and BCT motors, worm gearboxes with pre-stage for low speeds.
Packaging
Conveyors, filling, wrapping and labelling machines: BMT motors with BG or BV gearboxes for compact right-angle drives.
Hoisting and lifting
Applications needing safe stopping and holding: BCL brake motors and cast-iron BCT motors.
Assembly and disassembly
Modular gearbox configurations and accessories simplify integration and servicing.
Related Bernati ranges

worm gearboxes, compact housing
Compact worm gear reducers, sizes 030 to 090, ratios 7 to 100, up to 350 Nm.
- Sizes030 – 090
- Reduction ratios7 – 100
- Output torque≤ 350 Nm

three-phase motors, aluminium frame
Three-phase IEC motors in aluminium frames 56 to 160, IE1 / IE3 / IE4, 0.09 – 22 kW.
- IEC frame sizes56 – 160
- Rated power (kW)0.09 – 22
- Efficiency classesIE1, IE3, IE4

three-phase motors, cast-iron frame
Three-phase IEC motors in cast-iron frames 80 to 315, IE3 / IE4, 0.75 – 200 kW.
- IEC frame sizes80 – 315
- Rated power (kW)0.75 – 200
- Efficiency classesIE3, IE4