One question we’re often asked is, “What’s the difference between a urethane drive wheel and a urethane idler wheel?”

This is a great question!

What they have in common

  • Urethane drive wheels and idler wheels are similar in that they often feature hubs or cores.
  • They’re also used in many types of applications: industrial, material handling, manufacturing, and even food.
  • Finally, drive wheels and idler wheels are typically installed on production line shafts or within machinery or other units.

How they’re different

  • A drive wheel is attached to a shaft in such a way that when the shaft turns, the wheel must turn.
  • To ensure the wheel turns when the shaft turns, drive wheels incorporate some sort of positive means of engagement: a keyway, set screw, or an odd-shaped center (such as the middle wheel in the above photo).
The metal core for a urethane drive wheel featuring a keyway.

How drive wheels and idler wheels work

A drive wheel does a lot of work. It can help pull material through a production line. Drive wheels and rollers can be used to drive belts, as print rollers, or to propel a piece of machinery down a track.

They can also be used in conjunction with other wheels and rollers (such as a stain roller), turning at the same speed as a belt to apply coatings, or to transport a product, cart, or apparatus from one place to another.

A urethane drive wheel with keyway core and set screw.

An idler wheel, on the other hand, turns independently of the shaft to which it’s mounted. Idler wheels sometimes have bushings or bearings – or simply feature a hollow center (that is, no core or hub) – that allow the wheel to spin without restriction.

Other idler wheels feature a hub made of harder urethane – aka dual durometer idler wheels.

Dual durometer idler wheels.

Idler wheels do not have drive capacity. They simply turn. Or put another way, they follow the process or product.

Generally, urethane covered bearings are used in applications requiring a wheel without drive capacity as the bearings allow the wheels to spin unrestricted at high speeds.

No crush wheels, on the other hand, can bat from both sides of the plate. With the addition of a core and set screw, no crush wheels become drive wheels. As idler wheels or rollers, they tend to roll over material in place without crushing, pulling, or cracking it.

Urethane idler rollers used in the glass industry.

Our bonding makes the difference

What makes UI’s drive and idler wheels different is that we take the time to bond the urethane material to the core using either our proprietary chemical or mechanical bonding process (or both, depending on the application).

A chemical bond is when the hub is coated with a chemical, which creates a bond between the urethane cover and the core.

A mechanical bond is when the core or hub features grooves or pass-through holes. When the urethane is poured, it fills the grooves and makes a very tight mechanical bond – thus enhancing our substantial chemical bonding process.

Mechanical bond is usually used in more extreme or aggressive applications and is more costly to produce due to the machining involved.

Both the chemical and mechanical bonding process help reduce the potential for failure or slippage.

This means your drive and idler wheels last longer, especially for rigorous or high-speed applications.