• S flanges are made of high strength cast iron and are bored-to- size for a slip fit on standard shafts.
  • S flanges are easy to install, are readily available from stock in a wide range of popular bore sizes, and are supplied with two set screws at 90°.
  • The S Type coupling consists of two flanges and one sleeve.
Unit of Measure




Coupling Size

N/A 7S


N/A Coupling Flange


N/A Cast Iron


N/A Gray

Bore Type

N/A Finished Bore

Coupling Type

N/A S-Flex


N/A 3.11 lb

Dimensional Data

Bore Size

N/A 32.00 mm

Thread (Dimension T)

N/A 3/8-16

Keyway Size (W x D)

N/A 10 x 3.3 mm

Outside Diameter

N/A 4.625 in117.48 mm

Max. Bore (Dimension ID)

N/A 1.625 in

Dimension FL

N/A 0.780 in19.81 mm

Dimension HD

N/A 2.810 in71.37 mm

Dimension L

N/A 1.840 in46.74 mm

Dimension P

N/A 0.690 in17.53 mm

Dimension SL

N/A 0.350 in8.89 mm

Cubic inches

N/A 39.35875 in³

Performance Data

Nominal Torque (with EPDM Sleeve)

N/A 725 in·lb81.91 N·m

Max. Speed

N/A 5250.00 rpm

Torsional Stiffness

N/A 2769.00 in·lb/rad

Rated HP at 100 rpm

N/A 1.20 hp

Rated HP at 1,200 rpm

N/A 14.00 hp

Rated HP at 1,800 rpm

N/A 21.00 hp

Rated HP at 3,600 rpm

N/A 41.00 hp



  • All standard finished bore keyway flanges have 2 set screws at 90°.
  • Sizes 13, 14 and 16 RSB flanges are suitable for reboring and have two set screws at 90°.
  • Sizes 5-12 RSB flanges have no set screws.
  • Metric Bore / Keyway per DIN specifications.
  • Spacing between shafts should be greater than 1/8 inch and less than OAL minus the sum of the two bore dimensions.