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Date Updated:Nov. 26. 2025

Slip Torque of Coupling – Set Screw Type

Set screw type couplings secure the shaft directly using hexagon socket set screws.
Therefore, the slip torque is determined based on the coefficient of friction at the contact surface between the set screw and the shaft.

The slip torque values, calculated based on the test results, are shown below.

  • The load torque applied to the coupling must be less than the slip torque.
  • Slip torque varies depending on the operating conditions. Be sure to perform testing under the same conditions as actual use in advance.
  • Please check each product page for the set screw size and quantity for the corresponding product.
  • When two set screws are used, the slip torque represents the value when the set screws are positioned with a θ of 90°

    • 配置角度


    Aluminum Alloy Coupling

    The following test results were obtained by testing the material combinations shown in the table and are provided for reference only; they are not guaranteed values.

    Shaft S45C (Hardness: 16–27HRC)
    Hexagon Socket Set Screw SCM435 (Hardness: 45H)
    Ferrosoferric Oxide Film (Black)
    Hub Aluminum Alloy
    Anodized Finish

    slip-torqu

    M：Screw Diameter
    T：Screw Tightening Torque

    Stainless Steel Coupling

    The following test results were obtained by testing the material combinations shown in the table and are provided for reference only; they are not guaranteed values.

    Shaft S45C (Hardness: 16–27HRC)
    Hexagon Socket Set Screw SUSXM7 (Hardness: 21H)
    Hub SUS303

     

    M：Screw Diameter
    T：Screw Tightening Torque

    Carbon Steel Coupling

    The following test results were obtained by testing the material combinations shown in the table and are provided for reference only; they are not guaranteed values.

    Shaft S45C (Hardness: 16–27HRC)
    Hexagon Socket Set Screw SCM435 (Hardness: 45H)
    Ferrosoferric Oxide Film (Black)
    Hub S45C
    Ferrosoferric Oxide Film (Black)

     

    M：Screw Diameter
    T：Screw Tightening Torque
    Technical Data Technical Data Couplings