Borelli Group 3 Cast Iron Speed Increaser – 70012 Series
The Borelli Group 3 Cast Iron Speed Increaser – 70012 Series is a mechanical unit designed to connect gear pumps to the power take-offs of agricultural tractors. Featuring high-strength cast iron housings, it incorporates UNI 18NiCrMo5 steel gears (ISO/DIN 3990-80 standards) and UNI 16CrNi4 steel shafts. It supports a power rating of 37 kW, maximum operating temperatures of 120°C and output speeds of up to 3000 rpm, ensuring quiet operation.
The available product codes are: 70012 Series, Flange 96100, Flange 96101.
The Borelli Group 3 Cast Iron Speed Increaser – 70012 Series is specifically engineered to provide efficient and secure coupling between hydraulic gear pumps and the power take-offs (PTOs) of agricultural tractors. Since the standard PTO output speed is 540 revolutions per minute (rpm), this component serves as an essential mechanical interface to increase that speed to the optimal operating speeds required by hydraulic pumps. The system is also designed to accommodate different input speeds, provided that the output speed of the speed increaser never exceeds the critical limit of 3000 rpm.
The structural integrity of the unit is ensured by housings manufactured from cast aluminium and cast iron, materials specifically selected to provide excellent resistance to mechanical stress and exceptional structural strength. Power transmission is handled by gears designed in strict compliance with ISO/DIN 3990-80 standards. These gears are manufactured from special UNI 18NiCrMo5 steel. The gear teeth feature a corrected, low-profile geometry, a design solution intended to increase the fatigue resistance of the transmission mechanism and minimize noise emissions, ensuring exceptionally quiet operation. The transmission shafts, essential for mechanical reliability, are manufactured from UNI 16CrNi4 steel. They are connected to the gears through robust splined sections, a solution that maximizes the system’s ability to withstand the high transmitted torque loads specified in the catalogue.
The torque specifications declared for this series refer strictly to continuous-duty operating conditions. However, the system is designed to withstand operational overloads: under intermittent-duty conditions, the specified maximum torque ratings may be exceeded by up to 20%. Regarding thermal parameters, the design requires that the operating temperature during continuous duty never exceed 120°C, beyond which component integrity may be compromised. The unit transmits a rated power of 37 kW while maintaining a relatively low total weight of 14.5 kg.
Proper lubricant management is essential for the durability of the assembly. To ensure reliable operation and maximize the service life of the speed increaser, only SAE 90 oil must be used. The maintenance procedure requires the lubricant level to be visually inspected through the integrated sight glass every 1500 operating hours. The first oil change is a critical part of the running-in process and must be performed after the initial 60-80 hours of operation. The maximum oil filling capacity is 0.520 litres.
The primary application is mobile hydraulic equipment used in agriculture. Installing hydraulic pumps onto the speed increaser always requires a coupling half and a specific adapter flange. During installation, it is essential to identify the correct interface: the series supports SAE A Group 3 flanges (code 96100) and SAE B Group 3 flanges (code 96101), using PTO shafts with a 1″ 3/8 Z6 DIN 9611 A profile.
| Specification | Value |
|---|---|
| Housing Material | Cast aluminium and high-strength cast iron |
| Gear Material | UNI 18NiCrMo5 Steel (ISO/DIN 3990-80 Standards) |
| Shaft Material | UNI 16CrNi4 Steel |
| Input Speed (Power Take-Off) | 540 rpm |
| Maximum Output Speed | 3000 rpm |
| Rated Power | 37 kW |
| Maximum Operating Temperature | 120°C (continuous duty) |
| Recommended Lubrication | SAE 90 Oil (Maximum capacity 0.520 litres) |
| Oil Change Interval (First / Subsequent) | 60-80 hours / 1500 hours |
| Total Weight | 14.5 kg |
| Model / Ratio | Input Speed (rpm) | Output Speed (rpm) | Torque M2 (daNm) | Additional Details |
|---|---|---|---|---|
| 70012 Series – Ratio 1 | 540 | 540 | 66 | Main Product Family |
| 70012 Series – Ratio 1.5 | 540 | 810 | 44 | Main Product Family |
| 70012 Series – Ratio 2 | 540 | 1080 | 33 | Main Product Family |
| 70012 Series – Ratio 2.5 | 540 | 1408 | 26.4 | Main Product Family |
| 70012 Series – Ratio 3 | 540 | 1620 | 22 | Main Product Family |
| 70012 Series – Ratio 3.5 | 540 | 1836 | 18 | Main Product Family |
| 70012 Series – Ratio 3.8 | 540 | 2057 | 16.6 | Main Product Family |
| Code 96100 | – | – | – | SAE A Group 3 Flange |
| Code 96101 | – | – | – | SAE B Group 3 Flange |