Bonfiglioli WR75UD28150P71B5B3 Worm Gearbox
The Bonfiglioli WR75UD28150P71B5B3 worm gearbox is a W series right angle reducer configured with a P71 B5 motor flange and B3 mounting. The WR75 size is designed for robust industrial duty and is suitable for conveyors, mixers, and general machinery. The P71 B5 flange allows a standard IEC 71 frame motor with a B5 flange to be mounted directly to the gearbox. The B3 mounting provides a foot mounted base for secure installation.
Product Overview
The W series uses a worm and wheel design to achieve high reduction ratios in a single stage. A hardened and ground worm shaft drives a bronze worm wheel, producing smooth motion and low noise. The WR75 size offers high torque capacity in a compact housing. The UD configuration and 28150 code define the shaft, ratio, and mounting details of the unit. The P71 B5 motor flange and B3 mounting make the gearbox suitable for a wide range of industrial installations.
The gearbox housing is designed for rigidity so that the gear mesh remains stable under load. Bearings support the radial and axial forces generated by the worm gear action. Seals protect the lubricant and bearings from dust and moisture. Lubrication is contained within the housing and distributed to the gear mesh and bearings during operation. The cast iron construction supports heat dissipation and structural strength.
Construction and Design
The worm shaft is hardened and ground for smooth contact and reduced wear. The bronze worm wheel provides favorable friction characteristics and contributes to quiet operation. The housing maintains correct alignment between the worm and wheel under load. The P71 B5 interface is machined for precise motor mounting. The B3 foot mounting includes holes for securing the unit to a machine frame or baseplate.
The output shaft is machined to accept couplings, pulleys, sprockets, or other driven components. The housing design supports heat dissipation, which is important in worm gearboxes because sliding contact generates heat. Proper lubrication and clean exterior surfaces help maintain stable operating temperatures. The unit should be selected with an appropriate service factor for the application.
Performance Characteristics
The WR75 worm gearbox provides smooth and quiet power transmission across a range of input speeds. The sliding contact between the worm and wheel produces gradual torque transfer, which helps reduce shock in driven equipment. The reduction ratio of the unit determines the output speed and torque multiplication. The P71 B5 motor flange allows the gearbox to be paired with a matching motor for a compact drive package.
Worm gearboxes have a self locking tendency under many load conditions. This can be useful when the load must remain in position after the motor stops. However, self locking is not guaranteed in all conditions and should be verified for the specific application. Efficiency depends on the ratio, load, speed, and lubrication. Thermal capacity should be checked for continuous duty or high ambient temperatures.
Applications
The Bonfiglioli WR75UD28150P71B5B3 gearbox is suitable for belt conveyors, screw conveyors, mixers, agitators, packaging machines, and general industrial drives. The robust WR75 size is useful in applications that require higher torque capacity and reliable operation. The right angle layout allows the motor to be positioned at 90 degrees to the driven shaft, which can save space in machine frames.
The P71 B5 flange supports direct motor mounting, which simplifies alignment and reduces the number of separate transmission components. The B3 foot mounting provides a stable installation on baseplates and frames. The gearbox can be paired with standard three phase motors or other motors that match the interface. When variable speed operation is required, the motor and gearbox should be evaluated together.
Installation Guidelines
Installation should begin with a check of the nameplate data and a visual inspection of the gearbox. The unit should be mounted on a rigid base that can withstand the torque reaction. The B3 mounting bolts should be tightened to the recommended torque. The motor should be aligned with the P71 B5 flange so that the motor shaft engages the gearbox input correctly. The output shaft should be aligned with the driven equipment to avoid excessive loads on bearings and seals.
After installation, the gearbox should be checked for smooth rotation and correct oil level. A short run without load helps confirm that the assembly operates correctly. Any unusual noise, vibration, or temperature rise should be investigated before full service. Electrical connections to the motor should be made by qualified personnel following local regulations. Proper grounding and correct motor rotation direction are essential for safe operation.
Maintenance Recommendations
Regular maintenance supports reliable performance and long service life. Oil level and oil condition should be checked at recommended intervals. The first oil change should be performed after the initial running in period, and later changes should follow the schedule for the operating conditions. Seals and bearings should be inspected periodically. Leakage, abnormal noise, or vibration should be addressed promptly.
The exterior of the gearbox should be kept clean to support heat dissipation. Adequate airflow around the housing helps maintain stable temperatures. In dusty or humid environments, additional protection may be needed to prevent contamination. Maintenance records help identify trends and support planned servicing. Following a consistent maintenance schedule reduces the risk of unexpected downtime.
Selection Considerations
When selecting the WR75UD28150P71B5B3 gearbox, engineers should confirm the required output torque, output speed, duty cycle, and environmental conditions. The ratio and motor speed determine the output speed. The available torque depends on motor power and gearbox efficiency. A service factor should be applied for starting loads, shock loads, and continuous operation. The P71 B5 flange and B3 mounting must match the motor and machine.
The gearbox mounting position should provide adequate support and allow correct lubrication. The output shaft and mounting features should match the driven equipment. For applications that rely on holding or self locking, the load conditions should be evaluated carefully. Correct selection helps ensure smooth operation, stable thermal behavior, and long service life.
Conclusion
The Bonfiglioli WR75UD28150P71B5B3 worm gearbox offers a robust reduction solution with a P71 B5 motor flange and B3 mounting. Its cast iron construction and worm gear design support smooth torque transmission and reliable performance in conveyors, mixers, and industrial machinery. With correct installation and maintenance, the gearbox provides dependable operation and long service life.
