Sprag Clutch Guide

At GMN Bearing USA, we’re here to help you get the information you need fast, no matter where you are in your knowledge journey or your engineering project.

This Sprag Clutch Guide is designed to provide everything you need to know about clutches—what they are, what they do, how they are used. We’ve dissected each of the nuanced functions, theories and application types for sprag clutches, creating this practical, all-in-one reference tool.

This guide provides a general understanding of sprag clutches. GMN Bearing USA in- house engineers are happy to answer any of your questions and better learn how we can support your clutch needs.

Sprag Clutch 101

A sprag clutch goes by many names: One-way bearing, freewheel clutch, cam clutch, overrunning clutch. Whatever you call it, sprag clutches are a critical mechanical device in many heavy industrial applications—from automatic transmissions to torque converters, industrial winches to helicopter rotors. Learn how a sprag clutch works in our Sprag Clutch 101 guide.

Sprag Clutch Applications

Depending on your application, we offer several sprag clutches to choose from. To learn more about the ways a sprag clutch supports and controls an applications movement, check out our article 3 Ways a Sprag Clutch Stops the Rotation.

Sprag Clutches vs. Roller Ramp Clutches

Sprag clutches are similar in functionality to roller ramp clutches. However, sprag clutches have numerous benefits over roller ramp clutches, including simplified surfaces and engagement elements. Learn more about the various benefits of sprag clutches in this article.

Material & Wall Thickness Requirements

For optimal sprag clutch performance, GMN offers several recommendations for mating part material as well as wall thickness in our article Material & Wall Thickness Requirements.

Lubrication Requirements

Proper lubrication is crucial for sprag clutch performance. GMN recommends several oil and grease lubricants for many applications. Check out our recommendations in our Lubricating a Sprag Clutch: Best Practices Guide.

Torque and Hertzian Pressure

Torque capacity is one of the most important factors considered when selecting a clutch. In our Torque & Hertzian Pressure Guide, we will cover what torque capacity is, the effects of Hertzian pressure, and best practices to ensure optimal performance of your application.

Gap Height

Ensuring the gap height of your sprag clutch application is controlled as much as possible is crucial to performance. In our Gap Height article, we discuss the importance of the engagement curve and recommended shaft and housing tolerances and runouts.

Clamping Angle

At GMN Bearing USA, our sprag clutches have a unique design that ensures a proper clamping angle throughout the engagement zone. Learn more about clamping angles in this article.

Angle of Twist

The amount the mating components in a sprag clutch application rotate to reach equilibrium is known as the twisting angle, or angle of twist. Check out our Angle of Twist article to learn more.

Indexing Frequency

GMN Bearing USA offers sprag clutches that are designed for various indexing frequencies. Check out our helpful guide to Indexing Frequency.

RPM Effects

Looking for a way to calculate maximum RPM for your sprag clutch application? In this article, we cover maximizing and calculating RPMs, and solutions for your application.

Drag Torque

Drag torque occurs due to the pressure from sprags on the raceways. GMN products are designed to have little to no drag torque. Learn more with our Drag Torque Guide.

Springs

In a sprag clutch, springs are used to keep each sprag in contact with the mating surfaces while in a freewheeling stage. In our Sprag Clutch Springs Guide we discuss two spring types and their features.

Failure Mechanisms

• Sprag clutch failure can be broken down into three types:
• Overrunning failure
• Loading failure
• Cage failure

To learn more about these failure mechanisms and how to correct them, check out our Failure Mechanisms Article.

Why GMN

Our mission is to be a full-cycle resource for our customers through speed, agility and expert-level support. This empowers us to enrich the lives of our family, friends and community.

At GMN Bearing USA, we’re proud of what we do – helping engineers, spindle rebuilders and distributors find the right high-precision component… Fast! 

We opened in 1994 and are located in Houston, Texas. We are a precision component supplier of GMN manufactured products. Read More>>

How We’re Different

When selecting precision components, there are a lot of brands to choose from. We strive to build relationships, not just sell a precision component. We want to be on a first-name basis with our customers and be known for Quality in all we do.

Whether it’s shipping a precision component to a distributor or partnering with an OEM engineer to offer engineering support for a new application. We provide a quality-driven approach to all your precision needs. Read More >>

GMN’s Quality 360

Our quality measures go above what’s required of ISO standards, we check and triple-check every step from manufacturing to production to receiving and shipping. 

You might say we have control issues and we’re ok with that because we like the end results. For example, our quality control process for receiving and shipping has an internal accuracy rating of 99.9%. That means, what you order gets shipped out correctly, 99.9% of the time.

In this article read all about our Quality 360 approach to business.