What a Taper-Bushed Sheave System Does
A taper-bushed sheave is a stock sheave with a tapered bore that mounts onto a split, keyed bushing. The bushing clamps onto the shaft, and the sheave is drawn onto the bushing taper with cap screws. The result: one sheave catalog number fits multiple shaft sizes, mounting is fast, and removal is simple — no pullers, no heat, no damage to the shaft.
The Components
- Sheave body: single- or multi-groove, with a tapered bore matching a bushing series.
- Bushing: split tapered bushing with a finished bore for your shaft size (or a re-machinable bore for odd diameters).
- Cap screws: draw the sheave onto the bushing and lock the assembly.
Bushing Series and Bore Limits
Using the taper-bushed sheave catalog data RBC stocks, common bushing series include:
| Bushing | Max Bore | Typical Use |
|---|---|---|
| 1108 | 1.125" | Light 3V drives |
| 1610 | 1.625" | 3V and light 5V drives |
| 2517 | 2.5" | Heavy 5V drives |
| 3020 | 3.0" | Highest-capacity wedge sheaves |
Each bushing series also has a length through bore specification — for example, the 1108 has a 0.875" length, while larger series run longer. If your shaft has limited space for the hub, that dimension decides whether the assembly fits.
Pitch Diameter and Groove Selection
Sheave pitch diameters in the catalog range from 2.65" up to 25" for 3V stock sheaves, with larger sizes for 5V and 8V. The number of grooves (1, 2, or more) is determined by the horsepower the drive must transmit at your operating RPM. Matching the belt section (3V/5V) to the groove profile is non-negotiable — a 5V belt will not ride correctly in a 3V groove.
Why It Matters on the Plant Floor
When a drive needs a different speed or a shaft is replaced, a taper-bushed system lets you swap only the bushing — not the whole sheave. That is real inventory savings and real uptime protection.
Related catalog item: RBC Industrial stocks taper-bushed sheaves (3V, 5V, 8V), QD and MST sheaves, variable-pitch sheaves, and the full line of taper, QD, and MST bushings. Bring us your shaft size, desired speed ratio, and motor HP, and we will pull the right part numbers.
Call us at (915) 845-8188 to size your sheave and bushing package.