Bonfiglioli RAN series bevel gearbox selection and maintenance guide

Practical Guide for Engineering Selection and Maintenance of Bonfiglioli RAN Series Cone Gearbox

In industrial transmission systems, when power transmission needs to change direction, the bevel gearbox is an indispensable key component. The RAN series bevel gearbox launched by Bonfiglioli provides a reliable right angle transmission solution for applications such as conveying machinery, packaging equipment, lifting platforms, screw jacks, etc., thanks to its compact structure, multiple shaft arrangements, wide torque range, and extremely low maintenance requirements. This article will systematically explain the technical points of the RAN series in practical projects from the dimensions of engineering selection, installation alignment, lubrication and maintenance, and fault diagnosis, to help engineers fully tap into the performance potential of this series of products.

Overview of Product Series and Interpretation of Technical Parameters

The RAN series is a right angle bevel gear transmission unit, designed with quasi double curved or spiral bevel gears, featuring smooth transmission, strong load-bearing capacity, and high efficiency. This series covers a wide range of application scenarios from low power to high torque.

1. Torque and power range

Provides a rated torque range of 2.8 Nm to 3000 Nm, covering 9 machine base specifications (RAN 8 to RAN 48).

At an input speed of 1400 min ⁻¹, the mechanical power range is 0.15 kW to 90 kW, which can be matched with common industrial motor power.

The gear ratio range is 1.0 to 7.7. In addition to the 1:1 straight ratio, multiple reduction ratios are also available (such as the dedicated model with i=3), making it easy to achieve synchronous drive or multi axis speed matching.

2. Axis arrangement and output form

Input shaft: All are solid shaft inputs, providing single axis extension or dual axis extension options (for easy connection to encoders or auxiliary brakes).

Output shaft: Provides a hollow shaft form for key connection, making it convenient to directly fit onto the equipment shaft and saving coupling space; Solid shaft versions can also be provided according to demand (please refer to the ordering code for details).

Axis layout: Supports single-sided output and double-sided output, adapting to different mechanical layout requirements.

3. Thrust bearing capacity

The RAN series emphasizes the rated thrust capacity and is suitable for applications that require bearing axial loads, such as screw conveyors and mixers

RAN 1：50,000 N

RAN 2：80,000 N

RAN 2R：150,000 N

This characteristic gives it significant advantages in working conditions where it is installed vertically or subjected to large axial reaction forces.

4. Special models

The RAN 2R model provides an additional thrust carrying capacity of up to 150000 N, making it particularly suitable for screw jack applications such as lifting platforms, adjustment mechanisms, etc.

The suffix "R" for the model indicates a reinforced thrust design.

Selection calculation and engineering matching principle

The correct selection is the first step to ensure the long-term reliable operation of the bevel gearbox. Engineers need to verify based on actual operating parameters.

1. Determine the required torque and power

Calculate the reduction ratio i=n ₁/n ₂ based on the required torque (T ₂) and speed (n ₂) on the load side, and then deduce the input torque T ₁=T ₂/(i × η). The efficiency η of the RAN series is usually between 0.94 and 0.97 (depending on the speed ratio and lubrication conditions).

When selecting a model, the rated output torque should not be less than the actual load torque, and a safety factor of 1.2-1.5 times should be considered (especially for impact loads or frequent start stop conditions).

2. Verify radial and axial loads

Hollow shaft output is usually used for directly installing drive rollers or spiral shafts. At this time, it is necessary to verify the radial load that the shaft extension can withstand (specific bearing life data of the model needs to be consulted, and if the manual does not provide specific values, technical support can be consulted).

For applications that require significant axial force, such as vertical mixing and spiral extrusion, the RAN 1/2/2R series is preferred, and the corresponding specifications are selected based on the thrust value to ensure that the rated thrust is not exceeded.

3. Thermal power verification

When the ambient temperature is high (over 40 ℃) or the continuous operation time is long, the thermal capacity needs to be checked. The RAN series adopts a cast iron box with good heat dissipation performance, but it is still necessary to consider whether to install forced cooling (such as fans or cooling coils) according to actual working conditions.

4. Installation orientation and lubrication

Different installation orientations (horizontal, vertical, inclined) will affect the selection of lubricating oil level and the position of the vent valve. The manual does not specify all installation methods. In engineering, the installation posture needs to be indicated when ordering, and the manufacturer will provide corresponding oil level indicators and vent plug configurations.