Alignment Couplers | McMaster-Carr

Also called double-loop couplings, these have a flexible center that reduces vibration and compensates for high parallel and angular shaft misalignment.

Servomotor Precision Flexible Shaft Couplings

Able to handle high twisting forces as well as misalignment, these couplings are good for high-performance servomotor applications.

High-Speed Precision Flexible Shaft Couplings

With a bellows between two hubs, these couplings handle all types of misalignment and are good for precision stepper and encoder motion-control applications.

High-Speed Servomotor Precision
Flexible Shaft Couplings

Connect shafts and ball screws to high-speed servomotors and stepper motors—these shaft couplings handle four times more speed than standard servomotor couplings.

High-Misalignment Precision Flexible Shaft Couplings

Specially designed ridges allow these bellows couplings to compensate for more misalignment than other precision couplings—useful for low-torque, high-precision applications such as instrumentation and motion control.

Electrically Isolating Servomotor
Precision Flexible Shaft Couplings

An acetal plastic spacer at the center of these couplings insulates bearings, encoders, and other shaft components from stray electric current. Use them with servomotors, which sometimes generate current that travels down the shaft and can damage circuit boards, interfere with readings, and cause wear on bearing raceways.

Set Screw Flexible Shaft Couplings

Each hub includes a set screw (unless noted), which bites into your shaft to hold the coupling in place.

High-Torque Set Screw Flexible Shaft Couplings

The thick split spider on these couplings can take on twice as much torque as standard spiders, extending the life of bearings, seals, and motors.

Clamping Flexible Shaft Couplings

Designed to grip evenly around your shaft, these couplings provide more holding power than set screw couplings without marring the shaft.

Metal-Detectable Flexible Shaft Couplings

Designed for use in food-processing applications, where a fraying spider could contaminate a batch, these couplings have a metal-detectable rubber spider. Small pieces of metal inside the rubber will set off a metal detector, alerting you to the problem.

Clamping High-Parallel-Misalignment
Flexible Shaft Couplings

Designed to grip evenly around your shaft, these couplings provide more holding power than set screw couplings without marring the shaft.

Set Screw High-Parallel-Misalignment
Flexible Shaft Couplings

Each hub includes a set screw, which bites into your shaft to hold the coupling in place.

High-Angular-Misalignment Flexible Shaft Couplings

Also known as Schmidt couplings, these handle higher angular misalignment than other three-piece couplings. Good for applications with varying shaft misalignment, they're commonly used with conveyor rollers and roller feeds in printing and packaging machines.

Cleaned and Bagged Flexible
Heat-Resistant Shaft Couplings

Machinable-Bore Flexible Shaft Couplings

Customize the bore of these flexible couplings to align uncommon shaft sizes as well as shafts that have become undersized from wear or oversized from coatings.

Shock-Absorbing Flexible Shaft Couplings

A strip of flexible spring steel wraps around the teeth of both hubs to absorb sharp, momentary load increases that can come from motor startups, emergency braking, or sudden impact with hard objects.

Lightweight Flexible Shaft Couplings

Made with lightweight nylon sleeves, these gear couplings require less energy to move than other high-torque flexible couplings. They compensate for parallel, angular, and axial misalignment.

High-Speed Vibration-Damping Flexible Shaft Couplings

Use these gear-shaped couplings for high-speed and high-torque applications.

Vibration-Damping Flexible Shaft Couplings

A flexible tire on these couplings safeguards components on your shafts by reducing vibration and shock.

Ultra-High-Torque Flexible Shaft Couplings

With a rigid gear design, these steel couplings transmit more torque than other couplings of the same size.

High-Torque Flexible Shaft Couplings

With a rugged roller-chain design, these couplings provide excellent torque and angular misalignment capacities.

Noncontact Magnetic Shaft Couplings

Magnetic force transfers torque from one half of these couplings to the other; there’s no contact between the parts, so they won’t wear. Couplings compensate for angular and parallel misalignment.

Splined Flexible Shaft Couplings

For use with splined shafts, which are commonly found in gearboxes and pumps, these couplings are capable of transmitting more torque than couplings for round and keyed shafts.

Splined-to-Keyed Flexible Shaft Couplings

Connect splined shafts to keyed shafts. These couplings are commonly used to connect hydraulic pumps, compressors, and other heavy duty equipment, which often have splined shafts, to electric motors and other components that often have keyed shafts.

Constant-Velocity Single U-Joints

Keep shafts moving in sync with these U-joints—a flexible spring at the center stabilizes input and output speed and reduces vibration.

Keyless Locking Shaft Couplings for Overhung Loads

Support the weight of a motor and transfer torque to another shaft at the same time with these couplings.

Torque-Limiting Flexible Shaft Couplings

Protect shafts, motors, and gear boxes from damage that’s caused by torque overload from machine jams and emergency stops.

Connection-Severing Flexible Shaft Couplings

To protect power-transmission components from damage, these couplings will shear or tear in overtorque conditions (approximately 10-20 times the maximum rated torque) to sever connections between shafts.

Torque-Limiting Flexible Shaft Couplings with Alarm

If they exceed maximum torque, these couplings disengage, sound an alarm, and then automatically re-engage once the overtorque condition is eliminated.