Shaft collars are mechanical clamps used to limit, space, or position components on a shaft. Set-screw collars are widely used and affordable but can damage shafts. One-piece clamping collars offer better hold and less shaft damage. Two-piece (split) collars install without disassembling other parts. Common materials include steel, stainless steel, and aluminum, with finishes such as black oxide, zinc plating, passivation, and anodizing. Choose collars based on holding needs, environmental conditions, and whether retrofit installation is required.

What is a shaft collar?

A shaft collar is a simple mechanical component that clamps to a shaft to hold, space, or locate other parts. Also called shaft clamps or keyless locking assemblies, collars are common in machinery, automation, robotics, medical equipment, and general industrial applications.

Types of shaft collars

Set-screw collars

Set-screw collars are the most common and usually the most affordable option. They use one or more screws to bite into the shaft. They are easy to install but can mar the shaft surface and offer lower holding power than clamping designs.

One-piece clamping collars

One-piece clamping collars wrap around the shaft and tighten with a bolt or bolts. They distribute clamping force around the shaft, reduce surface damage, and provide higher holding torque than set-screw collars.

Two-piece (split) clamping collars

Two-piece collars split into two halves and fasten together around the shaft. Their main advantage is retrofit installation: you can fit them without removing other components from the shaft. They also deliver consistent clamping force and easier alignment during installation.

Materials and finishes

Manufacturers commonly make collars from steel, stainless steel, and aluminum. Steel collars often receive protective finishes such as zinc plating or black oxide. Stainless-steel collars may be passivated or electropolished for corrosion resistance, while aluminum collars are typically anodized to protect the surface and reduce wear.

Choose material and finish based on load, environment, and compatibility with the shaft and mating components. For example, stainless steel is typical in corrosive or hygienic environments; aluminum suits applications where weight matters.

Common uses

Shaft collars serve three primary roles:

  • Limiters: act as mechanical stops to limit shaft travel
  • Spacers: maintain axial space between components
  • Positioners: secure pulleys, bearings, sprockets, sensors, and other parts in place
You will find them on conveyor systems, motor shafts, linear stages, flagpoles, medical devices, and recreational equipment such as trailers and campers.

Choosing and installing collars - practical tips

Match the collar bore to the shaft diameter and pick a material that suits the environment. Use clamping collars when shaft surface preservation or higher holding torque matters. Use two-piece collars for retrofit work.

When using set-screw collars, consider using shafts with flats or hardened set screws to reduce slippage and local damage. For critical torque applications, consult the collar manufacturer for holding-torque data and proper tightening sequence.

Conclusion

Shaft collars are versatile, inexpensive components for positioning, spacing, and stopping parts on a shaft. Understanding the differences between set-screw, one-piece, and two-piece designs plus material and finish options will help you pick the right collar for your application.

FAQs about Shaft Collar

When should I use a set-screw collar?
Use a set-screw collar for simple, low-cost applications where shaft damage is acceptable or the shaft has flats. They suit low-torque, easy-to-service installations.
What are the benefits of clamping collars?
Clamping collars distribute force around the shaft, reduce surface damage, and provide higher holding torque than set-screw collars. They are better for repeated assembly and disassembly.
Why choose a two-piece collar?
Two-piece (split) collars allow installation without removing other components from the shaft, making them ideal for retrofit or maintenance tasks.
Which material should I pick for a corrosive environment?
Stainless steel collars offer superior corrosion resistance and are commonly used in corrosive or hygienic environments; finishes like passivation or electropolishing further improve resistance.
Do collars come with protective finishes?
Yes. Steel collars commonly get zinc plating or black oxide. Stainless-steel collars may be passivated or electropolished, and aluminum collars are often anodized.

News about Shaft Collar

New aluminium shaft collars are lightweight and easy to machine - Process and Control Today [Visit Site | Read More]

Quick-release shaft collar secures components on shafts - Machine Design [Visit Site | Read More]

Ruland releases quick-clamping shaft collars, requiring no installation tools - Design World [Visit Site | Read More]

Food-Grade Shaft Collars Promote Sanitation and Safety - Quality Assurance & Food Safety [Visit Site | Read More]

Shaft Collar and Coupling Manufacturer Introduces New Quick Adjust Line With Manual Positioning Capabilities - Thomasnet [Visit Site | Read More]

Keltbray secures contract with the Align JV to deliver key structural elements for the next two ventilation shafts on the Chiltern Tunnels Section of HS2 Phase One - Keltbray [Visit Site | Read More]

Keltbray secures HS2 ventilation shaft contract - Planning, Building & Construction Today [Visit Site | Read More]