Curved Jaw Couplings



Curved jaw couplings, also called spider jaw couplings, are 3-piece units comprised of two metal hubs (jaws) encapsulating an elastomeric element (the spider). The two jaws join loosely, and the elastomeric spider fills the gap between the jaws. Spider jaw couplings perform best in applications involving angular shaft misalignment; however, they can also handle small amounts of parallel misalignment.

There are several benefits of using curved jaw couplings:

  • Easy to install, disassemble, and visually inspect
  • Requires no lubrication for maintenance-free operation
  • Zero-backlash
  • No metal-to-metal contact between drive components

Finding the Right Curved-Jaw Coupling for Your Application

The compact design and flexible elastomer material allow for high torque capacity in misalignment applications. Examples of typical applications for curved jaw couplings include:

  • Gearboxes
  • Motor-driven machinery
  • Pumps

Selection criteria for multi-jaw couplings include torque requirements, linear and torsional vibration, shaft-to-shaft alignment, operating conditions, and space limitations. The spider component of jaw couplings determines the torque rating and how the collar responds to vibration, misalignment, high speeds, and exposure to chemicals or high temperatures. Because of this, it is vital to select an elastomer with the appropriate material properties for your application.

The Advantage for Curved Jaw Couplings

  • Zero backlash
  • Superior durability for long working life
  • Speeds up to 34,100 RPM
  • Torsional stiffness up to 33,000 in-lbs./rad
  • Torque values up to 3980 in-lbs.
  • Wide range of inch & metric jaw coupling bore sizes
  • Any bore-to-bore combination is possible within defined limits
  • Outstanding shock & vibration damping
  • Operating temperature range from -40°F (-40°C) to 212°F (100°C)
  • Resistant to oils, grease, and most solvents
  • Good atmospheric & chemical resistance