The SU Type coupling has a single flex plane, and is comprised of a single disc pack kit with two hubs. It is suitable for angular and axial misalignment only. Two SU couplings are often combined with a shaft to make a floating shaft coupling. The shaft can be hollow for long light weight floating shaft couplings.
Unit of Measure



N/A SU90-6 CPLG 1.251X1.251 KWSSBE

Bore Size  

N/A 1.251 & 1.251 in

Hub Style

N/A Standard


N/A Disc Coupling


N/A Steel


N/A Bored


N/A 3.39 lb


N/A Metallic

Coupling Series

N/A SU-6

Coupling Type

N/A Disc

Dimensional Data


N/A 90-6

Keyway Size (W x D)

N/A 1/4 x 1/8 Both Ends in

Set Screw Style Coupling Size (Dimension T)

N/A 1/4-20 Both Ends

Length thru Bore

N/A 1.570 in39.88 mm

Dimension FD

N/A 3.540 in90.00 mm

Overall Length

N/A 3.44 in88.00 mm

Max. Bore (Dimensions ID1/ID2)

N/A 1.5 in38 mm

Dimension HD

N/A 2.280 in58.00 mm

Distance between Shaft Ends (Dimension BSE)

N/A 0.295 in7.50 mm

Cubic inches

N/A 43.10870 in³

Performance Data


N/A -40 to 450 ºF

Nominal Torque

N/A 2100 in·lb

Max. Torque

N/A 4200 in·lb

Max. Speed (Unbalanced)

N/A 9100 rpm

Max. Speed (Balanced)

N/A 22700 rpm

Max. Angular Misalignment

N/A 1.50 º

Torsional Stiffness x 10^6 (of one disc pack)

N/A 2.40 in·lb/rad

Rated Power at 100 rpm

N/A 3.50 hp2.60 kW



  • Unitized disc pack
  • Infinite life when properly aligned
  • Torsionally rigid without any back lash
  • No need for lubrication or maintenance
  • No wearing parts and high resistance to harsh environmental conditions
  • Larger sizes are available upon request