Purchase now: Bonfiglioli W 75 U 50 P80 B5 B3 Gearbox
Purchase now: Atlantechdrives provides you the W 75 U 50 P80 B5 B3, a rugged, high-capacity universal worm gear reducer engineered by the power transmission experts at Bonfiglioli. Belonging to the heavy-duty W Series, this gearbox is specifically designed to handle intense torque applications where standard lightweight aluminum gearboxes would fail under shock loads. The «U» designation stands for a Universal cast-iron housing, precision-machined on all faces to provide unmatched mounting flexibility. Configured with a steep 50:1 reduction ratio and designed to accept a robust IEC P80 frame motor via a B5 large mounting flange, this unit delivers exceptional mechanical advantage. It acts as a massive torque multiplier, making it heavily utilized in aggregate conveyors, industrial mixing vats, heavy packaging lines, and continuous extrusion machinery where reliable 90-degree power transmission is critical.
Technical Specifications of the W 75 U 50 P80 B5 B3
The W 75 series utilizes a profile-ground steel worm shaft paired with a highly wear-resistant, centrifugally cast bronze worm wheel. This metallurgical combination ensures optimal sliding friction, reducing noise and extending the operational lifespan under continuous heavy-duty cycles.
- Part Number: W 75 U 50 P80 B5 B3
- Gearbox Series: W (Heavy-Duty Worm Gear Reducer)
- Frame Size: 75
- Housing Type: U (Universal, cast iron, multi-face mounting)
- Reduction Ratio (i): 50:1 (High ratio torque multiplier)
- Motor Interface: IEC P80 frame
- Motor Flange Type: B5 (Large standard flange)
- Mounting Position: B3 (Horizontal, foot mounted)
Expert Installation Advice: The B3 Mounting and Vent Plugs
Unlike smaller, sealed-for-life gearboxes, the W 75 size requires active thermal and internal pressure management. Expert Tip: This specific gearbox is ordered and configured for the B3 mounting position (horizontal, with the mounting feet located at the bottom). When the internal synthetic oil heats up during continuous operation, the air inside the cast-iron housing expands significantly. To prevent this pressure from blowing out the input and output oil seals, Bonfiglioli installs a breather/vent plug at the highest point of the gearbox based strictly on this B3 orientation. If you alter your machine design and mount this gearbox vertically on a wall without physically relocating the vent plug to the new highest port, the expanding oil will destroy the rubber seals, causing a catastrophic lubrication leak and gear seizure. Always verify plug locations before startup.
Maintenance: Lubrication and Thermal Limits
Worm gears naturally generate more heat than helical gears due to their sliding contact mechanics. During the initial 48-hour «running-in» period, the W 75 will run noticeably hotter than normal as the bronze wheel mates with the steel shaft. Ensure the gearbox is filled with the correct ISO VG synthetic gear oil. Periodically check the oil level sight glass. If the ambient temperature is extremely high, ensure there is adequate airflow around the cast-iron housing to prevent the oil from breaking down, losing its viscosity, and failing to protect the bronze wheel.
Frequently Asked Questions (FAQs)
Q: What size motor shaft does the P80 B5 input accept?
A: A standard IEC 80 frame motor with a B5 flange features a 19mm diameter shaft and a 200mm outer flange diameter. The gearbox input quill and mounting flange are perfectly matched to these standardized dimensions.
Q: Is a 50:1 ratio gearbox self-locking?
A: It is highly resistant to back-driving. While a 50:1 ratio enters the zone of «dynamic irreversibility,» heavy vibrations can sometimes break the static friction. If your application involves a safety-critical hoist or elevator, you must still employ an external failsafe electromechanical motor brake to guarantee the load will not fall when power is lost.
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