LT Series Two stage Crane Duty Gearboxes
Compact two-stage helical gearboxes for crane travel drives and lower-ratio duties. Three sizes, cast iron or fabricated steel housing, horizontal or vertical mounting.
Choose a size
Each size has its own page with full dimensions, power ratings and the GA drawing.
Nominal rating chart
Input power in kW at 1500, 1000 and 750 rpm. Select a size whose rating is at least your motor power multiplied by the service factor.
| Ratio i | Input rpm | LT-250 | LT-305 | LT-360 |
|---|---|---|---|---|
| 6 | 1500 | 18 | 35 | 52.5 |
| 1000 | 12 | 23.5 | 35.5 | |
| 750 | 9 | 18 | 27 | |
| 8 | 1500 | 16 | 31 | 45.5 |
| 1000 | 11 | 20.5 | 30 | |
| 750 | 8 | 15.5 | 23 | |
| 10 | 1500 | 12.5 | 25 | 37 |
| 1000 | 8.5 | 16.5 | 24.5 | |
| 750 | 6.5 | 12.5 | 18.5 | |
| 12 | 1500 | 10.5 | 20 | 27.5 |
| 1000 | 7 | 13.5 | 18.5 | |
| 750 | 5.5 | 10 | 14 | |
| 14 | 1500 | 9 | 17.5 | 24 |
| 1000 | 6 | 12 | 16 | |
| 750 | 4.5 | 9 | 12 | |
| 16 | 1500 | 7.5 | 15 | 21.5 |
| 1000 | 5 | 10 | 14.5 | |
| 750 | 4 | 7.5 | 11 | |
| 18 | 1500 | 6.5 | 13.5 | 18.5 |
| 1000 | 4.2 | 9.5 | 12.5 | |
| 750 | 3.2 | 7.5 | 9.5 | |
| 20 | 1500 | 5.8 | 12 | 17.5 |
| 1000 | 3.8 | 8.5 | 11.5 | |
| 750 | 2.9 | 6 | 9 | |
| 22 | 1500 | 5.3 | 10.5 | 15 |
| 1000 | 3.5 | 7 | 10 | |
| 750 | 2.6 | 5.5 | 8 | |
| 26 | 1500 | 5 | 9.8 | 14 |
| 1000 | 3.2 | 6.5 | 9.4 | |
| 750 | 2.5 | 5.1 | 7.5 |
Ratings from the J.S. Gear Crane Duty catalogue, Edition 2027. – means the ratio is not available in that size.
General arrangement
Frequently asked
Are the gearboxes supplied with oil?
No. Gearboxes are supplied without oil unless the order specifies it. Fill mineral oil of ISO VG 320 or 460 to the oil level indicator before commissioning, and change it every 4,500 operating hours under standard conditions.
Cast iron or fabricated housing: which should I choose?
Graded cast iron (CI body) is the standard housing. A fabricated steel housing is available on request in the standard sizes, and the heavy duty sizes marked F are made in fabricated steel only.
Do you make a hollow output shaft?
No. All J.S. Gear crane duty gearboxes have a solid output shaft. For a drum, mount it directly on the output shaft within the permissible overhung load, or use our standard gear ring arrangement.
Can you supply a direct replacement for another make?
We supply our standard models with a general arrangement (GA) drawing so you can check the fit against your existing mounting. We do not copy other makes one-to-one.
Is the ratio exact?
Catalogue ratios are nominal. The actual ratio of each size is shown on the model page and confirmed on the certified GA drawing.
Need a price or a certified GA drawing?
Send us your motor power, speed and ratio.