The Curved Jaw coupling consists of two standard hubs and one elastomeric spider.

    Elastomeric spiders are offered in four different shore hardnesses:

    80 Shore A (Blue) - offering good dampening properties
    92 Shore A (Yellow) - for general and hydraulic applications
    95/98 Shore A (Red) - for high torque requirements
    64 Shore D(Green) - for high humidity environments
Unit of Measure





N/A Jaw

Spider Type

N/A 98 Shore A


N/A Polyurethane


N/A Open Center


N/A Red

Coupling Type

N/A Elastomeric Insert

Stock Sizes

N/A 14 - 180


N/A 0.25 lb

Dimensional Data

Spider Size

N/A 42

Set Screw Size

N/A 5/16-18

Set Screw Style Coupling Location Size (Dimension SL)

N/A 0.790 in20.07 mm

Outside Diameter

N/A 3.74 in95 mm

Spider Outside Diameter (Dimension A)

N/A 3.740 in95.00 mm

Spider Inside Diameter (Dimension H)

N/A 1.810 in46.00 mm

Spider Thickness (Dimension W)

N/A 0.790 in20.00 mm

Dimension G

N/A 1.020 in25.91 mm

Dimension S

N/A 1.810 in45.97 mm

Distance between Spider and Hub Face (Dimension CL)

N/A 0.120 in3.05 mm

Cubic inches

N/A 11.05020 in³

Performance Data

Normal Temperature Range

N/A -40 to 212 ºF

Max. Temperature Range

N/A -40 to 248 ºF

Nominal Torque

N/A 3980.00 in·lb450.00 N·m

Max. Torque

N/A 7960.00 in·lb899.00 N·m

Max. Speed

N/A 6000 rpm

Angular Displacement

N/A 0.070 in

Max. Angular Displacement (∆ Ka), n=1500 [1/min]

N/A 1 º

Max. Axial Displacement (∆ Ka)

N/A 0.0790 in

Max. Radial Displacement (∆ Kr)

N/A 0.0120 in

Axial Misalignment

N/A 0.039 to 252 in

Angular Misalignment

N/A 0.90 to 1.30 º

Parallel Misalignment

N/A 0.008 to 0.027 in

Wind-Up Angle at Nominal Torque

N/A 3.20 º

Wind-Up Angle at Max. Torque

N/A 5.00 º

Rated HP at 1,200 rpm

N/A 75.00 hp

Rated HP at 1,800 rpm

N/A 110.00 hp

The Curved Jaw Design

The Curved Jaw Design

  • Three piece design that is easy to assemble
  • The curved jaw design incorporates both radial and axial curvature (crowning) to the elastomer (spider)
  • Hubs are offered in sintered iron, steel, aluminum, cast iron and nodular iron materials
  • Three different urethane elastomers available
  • No metal to metal contact and no lubrication required
  • Fail safe design due to the jaw in compression design (continues to function after the elastomer fails)
  • The CJ series covers a torque range of 67 to 247,800 in-lbs

Elastomer Characteristic

Elastomer Characteristic

  • Four types of spiders are available for the CJ Series of couplings
  • Urethane spiders provide high abrasion resistance and elasticity, along with good damping characteristics
  • The spiders are offered in a variety of shore hard nesses, each providing a different level of torque capacity, damping, and chemical resistance
  • The 92A shore insert (yellow in color) is the standard, offering excellent torque carrying capacity
  • The 80A shore insert (blue) offers the best damping characteristics
  • The 95/98A shore spider (red) offers higher torque than the standard 92 shore, but retains greater damping capacity compared to the 64D shore insert (green)
  • The 64D shore insert is offered for high humidity environments, higher temperatures, and offers the highest torque capacity
  • The standard curved jaw spider design has a hole in the center to accommodate small between shaft end measurements
  • The 80A, 92A, and 95/98A shore spiders have a temperature capacity of 212° F
  • The 64D shore spider has a temperature capacity of 230° F
  • The curved jaw spider’s urethane material also resists oil, dirt, sand, grease, moisture, many solvents, as well as atmospheric effects of ozone

Application Types Requiring

Application Types Requiring

N/A High Torque Requirements



  • Maximum bore may be achieved through the use of a shallow keyway.
  • Maximum bore refers to maximum straight bore with keyway allowed in hub.
  • Outside Diameter is equal to Dimension HD for B style aluminum sizes: 19, 24, and 28.
  • S = Solid hub with no bore
  • Spider Outside Diameter (Dimension A) is equal to Outside Diameter
  • The values regarding displacement are provided assuming normal operating conditions (i.e. temperature, torque with nominal rating of the coupling, speed/ RPM rating of the coupling, and misalignment).
    Careful installation (i.e. alignment) and periodic inspection should be provided to provide the optimum life of the coupling. Special consideration should be given as to the position of the shafts and the amount of axial movement the coupling will be exposed to.
    The more accurate the alignment of the coupling, will result in greater life of the elastomer. A coupling guard and rotating equipment safety procedures should always be followed.
    Please consult the Lovejoy web site at for assembly instructions of the curved jaw coupling.