A complete CJ Series coupling is comprised of two standard CJ hubs and one CJ spider. Four types of spiders are available for the CJ Series.
Unit of Measure



N/A CJ 55/70BX HUB STL 2" 1/2KW

Hub Style



N/A Curved Jaw Coupling Hubs

Hub Material

N/A Steel


N/A Bored

Coupling Type

N/A Jaw


N/A 8.05 lb

Dimensional Data

Bore Size 

N/A 2 in

Coupling Size

N/A 55

Set Screw Style Coupling Size (Dimension T)

N/A 3/8-16

Keyway Size

N/A 1/2 x 1/4 in

Length thru Bore (Dimensions LTB1/LTB2)

N/A 3.540 in89.92 mm

Outside Diameter

N/A 4.720 in119.89 mm

Overall Coupling Length

N/A 4.560 in115.82 mm

Spider Outside Diameter

N/A 4.720 in120.00 mm

Spider Inside Diameter

N/A 2.360 in60.00 mm

Spider Thickness (Dimension W)

N/A 0.870 in22.00 mm

Set Screw Style Coupling Location Size (Dimension SL)

N/A 0.790 in20.07 mm

Min. Bore (Dimensions ID1/ID2)

N/A 0.470 in12 mm

Max. Bore (Dimensions ID1/ID2)

N/A 2.750 in70.00 mm

Dimension G

N/A 1.180 in29.97 mm

Dimension HD

N/A 4.720 in119.89 mm

Distance between Spider and Hub Face (Dimension CL)

N/A 0.160 in4.06 mm

Cubic inches

N/A 78.86554 in³

Performance Data

Normal Temperature Range (with 80 Shore A, 92 Shore A, and 95/98 Shore A spiders)

N/A -40 to 212 ºF

Max. Temperature Range (with 80 Shore A, 92 Shore A, and 95/98 Shore A spiders)

N/A -50 to 248 ºF

Nominal Torque (with 92 Shore A spider)

N/A 3625.00 in·lb

Max Torque (with 92 Shore A spider)

N/A 7250.00 in·lb

Max. Speed

N/A 4750 rpm

Angular Displacement

N/A 0.090 in

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

N/A 1.10 º

Max. Axial Displacement (∆ Ka)

N/A 0.8700 in

Max. Radial Displacement (∆ Kr)

N/A 0.0140 in

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



  • 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 www.lovejoy-inc.com for assembly instructions of the curved jaw coupling.