YOXP Connection Dimension Data Sheet for Pulley-Type Torque-Limiting Fluid Coupling

Structural characteristics, performance, and selection precautions

• The output and input are on the same end, used for mechanical equipment with parallel transmission. Generally, the coupling is suspended on the motor shaft. (See Fig. 1)
• When the working machine speed is higher than the motor speed, the coupling should be suspended on the main shaft of the working machine. (See Fig. 2)
• It can be used in vertical applications, and there are two mounting types: suspended type (Fig. 3) and seated type (Fig. 4). This must be specified when placing an order.
• When the coupling and pulley are excessively large in size and weight, and the overhang is too long resulting in excessive bending moment, it is recommended to adopt the double-support structure shown in Fig. 5, or the structure with support at the opposite end as shown in Fig. 6.
• Tension bolts should be used to fasten the coupling to the motor shaft to prevent the coupling from detaching from the motor shaft. The user is required to drill and ream a tapped hole on the motor shaft to match the tension bolt. (See Fig. 7)
• The pulley is equipped with internal bearings, providing good centering and stable, reliable support. However, the outer diameter of the pulley should not be too small; otherwise, there will be insufficient space to accommodate the bearings.
• Various performance parameters are basically the same as those of the direct-coupled torque-limiting fluid coupling.
• Due to the relatively low transmission efficiency of the V-belt drive, the overall efficiency of the V-belt

pulley coupling can reach a maximum of only η = 0.92. To prevent overheating of the coupling, a power margin

should be reserved during selection.

• For V-belt pulley couplings driven by two-speed motors,

 Functions and Applications of Torque-Limiting Fluid Coupling

Functions: Provides light-load start-up, overload protection, impact dampening, torsional vibration isolation, load equalization for multi-drive systems, flexible braking, and energy efficiency.

1. The motor starts under near-no-load conditions, reducing starting time and starting current, and minimizing impact on the power grid.
2. It allows starting with the motor's peak torque, thereby enhancing the motor's starting capability and avoiding the "over-sized motor for under-sized load" phenomenon. Compared with rigid drives, it can reduce the motor frame size by at least one grade.
3. It enables the use of economical and low-cost squirrel-cage motors as a replacement for expensive wound-rotor motors.
4. It protects both the motor and the driven machine from damage during overload conditions, reduces failure rates, and extends service life.
5. The starting torque of the driven machine can be controlled, allowing extremely smooth starting and acceleration of heavy-load, high-inertia equipment.
6. As a flexible drive, it cushions impact loads and isolates torsional vibrations.
7. In multi-motor drive systems, it enables sequential start-up of the motors, balanced load sharing, and synchronized operation.
8. It provides wear-free power transmission, with no direct mechanical friction except for bearings and oil seals.
9. It is easy to operate, maintain, and service, with low maintenance costs and a long service life.
10. It features low initial investment and high cost-effectiveness, with energy-saving rates reaching 8–15%.

Applications: Suitable for all types of machinery and equipment that require light-load starting, overload protection, torsional vibration isolation, coordinated multi-motor driving, and flexible braking.

Applications:

Mining – Ball mills, rod mills, crushers, feeders, rotary screens, belt conveyors, excavators, bucket-wheel excavators, hoists, fans, and water pumps.

Electric Power – Coal pulverizers, belt conveyors, bucket-wheel stacker-reclaimers, air preheaters, cable-laying tow trailers, and slag crushers.

Metallurgy – Belt conveyors, steel plate lifting machines, forging feeders, overhead cranes, excavators, bridge cranes, coal pulverizers, gantry cranes, balling machines, straightening machines, and crane cable reeling mechanisms.

Coal – Scraper conveyors, belt conveyors, coal cutters, car dumpers, crushers, ploughs, transfer machines, coal feeders, and screw conveyors.

Petroleum – Mud separators, beam pumping units, oil well pumps, and drilling rigs.

Leather – Dryers, staking machines, drums, and paddle vats.

Construction – Tower cranes, concrete mixers, asphalt mixers, graders, pavers, gantry cranes, brick-making machines, belt conveyors, and crane cable reeling structures.

Building Materials – Ball mills, wet pan mills, crushers, pug mills, drawbenches, mixers, belt conveyors, and plate chain elevators.

Grain, Oil & Food, Pharmaceutical – Mixers, vegetable oil separators, frame saws, belt conveyors, tube bundle dryers, centrifuges, starch separators, cane crushers, buried scraper conveyors, and gantry cranes.

Chemical Industry – Sand mills, coating machines, mixers, dryers, centrifuges, belt conveyors, and pelletizers.

Ports – Belt conveyors, grain conveyors, coal cutters, gantry cranes, tower cranes, and buried scraper conveyors.

Textile – Carding machines (for cotton and wool), rope-making machines, lap winders, lap combiners, and rotor spinning machines.

Amusement – Various rotary amusement rides and ski lift towing machines.

Transportation – Canal lock gate openers, railway foundation excavators, snowplows, automotive plant overhead conveyors, garage door openers, gantry cranes, tower cranes, and subway air conditioning systems.

Posts & Telecommunications – Parcel sorting machines and overhead chain conveyors.

Light Industry – Beer filling machines, rotary advertising lighting fixtures, tobacco dryers, carpet washing machines, dewatering machines, glass crushers, and chain tensioning devices for tinplate printing machines.

Woodworking – Particleboard laying machines, hoisting machines, wood veneer lathes, shredders, and bark separators.

Foundry – Sand mixers, shot blasting machines, and gantry cranes.

Rubber & Plastics Machinery – Injection molding machines, extruders, and rubber mixing mills.