Purchase now: Bonfiglioli W 75 U 100 P71 B5 B3 Gearbox
Purchase now: Atlantechdrives provides you the W 75 U 100 P71 B5 B3, a highly robust, industrial-grade universal worm gear reducer expertly engineered by the global power transmission specialists at Bonfiglioli. Belonging to the exceptionally durable W Series, this heavy-duty gearbox is specifically designed to handle intense torque applications, continuous duty cycles, and severe radial shock loads that would easily shatter standard lightweight aluminum drives. The «U» designation stands for a Universal unibody cast-iron housing, precision-machined on multiple geometric faces to provide unmatched mounting flexibility in complex industrial machine frames. This specific unit is configured with an extreme 100:1 reduction ratio, making it the absolute perfect 90-degree transmission for ultra-slow, high-torque applications such as heavy-duty inclined safety conveyors, massive rotary mixing vats, precise positioning tables, and automated heavy extrusion machinery. Designed to seamlessly accept a standard IEC P71 frame electric motor via a large B5 mounting flange, it offers a formidable blend of extreme torque multiplication, spatial efficiency, and uncompromising mechanical durability.
Technical Specifications of the W 75 U 100 P71 B5 B3
The W 75 series utilizes a profile-ground steel worm shaft paired with a highly wear-resistant, centrifugally cast bronze worm wheel. Under the intense sliding friction of a massive 100:1 ratio, this premium metallurgical combination ensures optimal heat dispersion, drastically reducing operating noise and extending the lifespan under brutal 24/7 operations.
- Part Number: W 75 U 100 P71 B5 B3
- Gearbox Series: W (Heavy-Duty Cast Iron Worm Gear)
- Frame Size: 75 (Industrial cast iron frame)
- Housing Type: U (Universal, multi-face mounting)
- Reduction Ratio (i): 100:1 (Ultra-low output speed, extreme torque)
- Motor Interface: IEC P71 frame
- Motor Flange Type: B5 (Large standard mounting flange)
- Mounting Position: B3 (Horizontal, foot mounted)
Expert Tips: The Physics of a 100:1 Ratio
Understanding mechanical holding power and thermal efficiency is absolutely vital when dealing with ultra-high worm gear ratios like the 100:1. Expert Tip: The 100:1 reduction ratio provides massive mechanical leverage, firmly placing the W 75 into the category of absolute static irreversibility (self-locking). It acts as a highly effective, natural mechanical brake, securely holding suspended loads perfectly stationary when the motor turns off. However, this massive ratio also means the gearbox is mechanically inefficient. A large percentage of the electrical motor’s power is converted directly into sliding friction (radiant heat) rather than rotational output. You must carefully calculate your required output torque and never heavily oversize your electric motor without verifying the thermal dissipation capacity of the cast-iron housing, or the internal oil will boil and destroy the seals.
Maintenance: Thermal Management in High-Ratio Drives
Unlike smaller fractional aluminum gearboxes, the heavy-duty W 75 cast-iron size requires active internal pressure management, especially with a 100:1 ratio that generates massive amounts of heat. This specific gearbox is configured from the factory for the B3 mounting position (horizontal, with the integral mounting feet at the bottom). As the high-ratio friction heats the internal synthetic ISO VG gear oil during operation, the air inside the rigid housing expands significantly. To prevent this expanding pressure from blowing out the critical input and output rubber 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, you must physically relocate the vent plug to the new highest port.
Frequently Asked Questions (FAQs)
Q: What size motor shaft does the P71 B5 input accept?
A: A standard IEC 71 frame motor features a 14mm diameter solid shaft. The B5 mounting flange for the 71 frame has an outer diameter of 160mm. The gearbox input quill and mounting face are perfectly matched to these standard IEC dimensions.
Q: Can I use standard automotive gear oil in the W 75?
A: No. High-performance industrial worm gears operating at extreme ratios like 100:1 require specific, high-quality synthetic gear oil to handle the extreme pressure (EP) sliding friction and elevated operating temperatures. Using standard mineral or automotive oil will cause premature bronze wheel failure.
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To ensure maximum mechanical synergy across your production line, this universal worm gear unit can be synchronized with a reliable high-speed power source such as the BN 90S 2 230/400-50 IP55 electric motor.
