Rigid Couplings
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Rigid Shaft Couplings from Ruland



Rigid Shaft Couplings are available in carbon steel, aluminum and stainless steel.Rigid shaft couplings are available in one and two-piece designs, with and without keyways, in aluminum, carbon steel, and stainless steel. A large number of standard sizes are available in straight and step bore combinations to fit shafts ranging from 1/8" to 2" in the inch series and from 3mm to 50mm in the metric series. Inch to metric conversion couplings are also available by special order. Each rigid coupling is stamped with the Ruland name and the bore sizes for easy identification.

The one-piece rigid coupling wraps around the shaft, providing high torsional holding power without the shaft damage and fretting inherent when set screw style couplings are used. The two-piece rigid coupling has the additional benefit of allowing for disassembly and maintenance without removal of other components. The two-piece design also features opposing hardware for dynamic balancing.

Extra steps are taken in the manufacture of rigid couplings to provide important performance benefits. As one of these steps, the bores of Ruland straight bore rigid shaft couplings are precision honed. Honing of the bores provides several benefits that enhance the overall performance of the rigid coupling. Applications that require strict control of shaft alignment benefit greatly from honing, which assures both bores are collinear. Honing also corrects any residual distortions caused by stresses introduced during the manufacturing process, resulting in a round, precisely sized bore. Proper sizing and geometry assures a large percentage of shaft contact and greater torque transmission ability.

Rigid couplings come with Ruland's unique Nypatch® socket head cap screws for increased performance and reliability. Nypatch® is a proprietary process that involves depositing a 360 degree coating of Nylon on several threads of the socket head cap screws. This coating is designed to reduce screw vibration, which can cause the screws to loosen and torque transmission ability to diminish during the course of normal use. The Nylon also provides the necessary dissimilar material to reduce galling of the screw threads in stainless steel rigid couplings.

Double wide shaft collars are an excellent alternative to rigid shaft couplings in applications where space is limited. The double wide shaft collar has a reduced torque capability compared to the rigid coupling due to its use of a single socket head cap screw per shaft. However, the compact size of the collar reduces inertia making it ideal for motion control applications.

The benefits of using rigid shaft couplings include their economy, high torque capacity, and zero backlash. Rigid couplings are suitable for applications when misalignment is neither present nor desired, including connecting line-shafting or attaching a motor to a gearbox.

Rigid couplings are increasingly used in precision motion control applications where components are properly aligned. Read the article "Rigid Couplings for Precision Motion Control Applications" to learn how a rigid shaft coupling can be used in servo applications.

Why Ruland

  • Step-bore rigid couplingOnly manufacturer with precision honed bores on straight bore rigid couplings for superior fit and torque transmission and alignment.
  • Ruland rigid couplings do not introduce misalignment, vibration, or bearing noise into the system making them suitable for high precision servo applications and shaft to shaft connections.
  • Highest grade forged screws (DIN 12.9 for metric screws) test to or beyond industry standards for maximum torque ability.
  • Proprietary Nypatch® coating on hardware provides even seating of the screw, repeated screw installations and prevents galling.  Nypatch® hardware also resists vibration and maintains holding power.
  • In house proprietary black oxide process produces a fine glossy finish while increasing holding power and resisting corrosion.
  • The cross cut design ensures a proper clamp on both shafts because it can accommodate slight deviations in the size of the shafts being connected.
  • Opposing screws balance the two-piece coupling to reduce vibration and have higher speed capabilities.
  • Keyways are available as a standard in two-piece rigid couplings.  Step bore combinations including inch to metric are also available.
  • Available in a variety of sizes and materials including lead-free steel, stainless steel, and high grade aluminum (for low inertia).


CLX Rigid Coupling
CLX One-Piece
Inch Dimensions
MCLX Rigid Coupling
MCLX One-Piece
Metric Dimensions
CLC Rigid Coupling
CLC One-Piece
Inch with Keyways
MCLC Rigid Coupling
MCLC One-Piece
Metric with Keyways
SPX Rigid Coupling
SPX Two-Piece
Inch Dimensions
MSPX Rigid Coupling
MSPX Two-Piece
Metric Dimensions
SPC Rigid Coupling
SPC Two-Piece
Inch with Keyways
MSPC Rigid Coupling
MSPC Two-Piece
Metric with Keyways
SCX Rigid Coupling
SCX Set Screw
Inch Dimensions
MSCX Rigid Coupling
MSCX Set Screw
Metric Dimensions
SCC Rigid Coupling
SCC Set Screw
Inch with Keyways
MSCC Rigid Coupling
MSCC Set Screw
Metric with Keyways
WCL Shaft Collar
WCL Double Wide
Inch Dimensions
MWCL Shaft Collar
MWCL Double Wide
Metric Dimensions
WSP Shaft Collar
WSP Double Wide
Inch Dimensions
MWSP Shaft Collar
MWSP Double Wide
Metric Dimensions

Custom Designs

Custom Rigid CouplingAs a service to our customers, we offer our vast machining experience and talents to meet special needs with custom parts. Our shop is equipped with the machines and skilled people necessary to fill all of your special requirements. If you don't see what you are looking for in our standard line, please inquire about our custom fabrication service.

Examples of Past Specials:

  • Three-piece rigid couplings
  • Rigid couplings without center cuts
  • Special bore sizes and geometry
  • Special lengths, widths and outside diameters
  • Special material and hardware requests
  • And Many Others... Please Contact Us for More Information

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Ruland Rigid Shaft Couplings

Rigid Shaft Coupling

Rigid Shaft Coupling

Set Screw
Rigid Shaft Coupling

Double Wide
Shaft Collar

Double Wide Shaft Collar Set Screw Rigid Coupling Two-Piece Rigid Coupling One-Piece Rigid Coupling