Industrial Pulleys Sheaves
An industrial pulley is a simple machine used in conjunction with conveyor belts and pumps to help accomplish general hoisting and holding tasks. A sheave is a single wheel in an industrial pulley assembly, which are common components in belt drives. They are also often found in block and tackle assemblies, conveyors, and linear slide rails.What is the difference between friction sheaves and timing sheaves?
Friction sheaves have a smooth outer edge and function by allowing the belt drive to drag on the outer edge, creating friction that transfers energy between the industrial sheave and the belt. Timing sheaves contain teeth that fit into grooves in the belt. They are sometimes called "positive drive" or "synchronous." The teeth grip the belt and maintain precise positions over long periods of time.How do you choose a sheave for an industrial pulley?
If you are replacing a worn or broken industrial pulley, the easiest approach is to match the manufacturer's specifications exactly. When selecting for a new application, consider factors such as shaft diameter, bearings, tension, belt width, timing, and RPM. The keyway or spline placement must be compatible with the axle on which you wish to mount the pulley. Don't forget to check your specific requirements such as solvent resistance, high or low temperatures, and continuous use.How do you choose a timing pulley?
A timing pulley differs from other industrial pulleys in that one or more of its sheaves contains teeth for use with a timing belt. The teeth allow the belt to be operated with less risk of slippage than with other industrial pulleys but require additional considerations and maintenance. Ensure that the tooth pitch, spacing, size, and shape match your application.
- Tooth pitch
- Other factors
The diameter of an industrial sheave can be measured by running a string around its outer edge at its narrowest point and then measuring the length of the string. Wrap the string repeatedly and mark it so that one mark touches each string wrap. Measure the distance between points with a tape measure or ruler, take the average, and divide by pi.What size belt should you use with the sheaves?
The belt size can be determined by a simple formula, L = 2C + 1.5708 (D + d), where L is the length, C is the distance between sheave centers, D is the size of the first sheave, and d is the size of the second sheave.