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TOOLS & RESOURCES

Support Unit Selection Guide and Recommended Selection Procedure

Published:2025-06-11 12:03:26

  1. Fully understand the load capacity, rigidity requirements, and end dimensions of the ball screw, trapezoidal screw, or ball spline, as well as the assembly characteristics of the entire transmission system.

  2. Determine the mounting method of the bearing block: axial or radial.

    • Axial-mounted support units include: FF, FK, FK-E, FK-TAC, FKA, FBSA, WBK, MBK, FF.

    • Radial-mounted support units include: EK, EK-E, EK-TAC, EF, BF, BK, BK-E, BK-TAC, AK, AF, LF, LFA, SBK, SBK-U.

  3. For axial mounting:

    • In heavy-duty machine tool applications, choose FBSA or WBK types.

    • For engraving machines or small machining centers, MBK and FK-TAC types are recommended.

    • For automation equipment, FK, FKA, or FK-E are recommended, with FF for the support side.

    • When the length-to-diameter ratio of the rotating screw (screw total length / screw outer diameter) exceeds 50, it is recommended to use the same support units type for both fixed and support ends, adopting a double-tension mounting method.

    • Once the bearing block type is selected, choose the specific size based on the screw shaft end dimensions.

  4. For radial mounting:

    • First, select the support unit specification based on the screw shaft end dimensions.

    • Then determine the type based on the center height in the assembly layout to finalize the model.

    • The selected bearing block should meet the axial load capacity requirements.

    Allowable axial load capacity ranking for radial-mounted support units of the same specification:
    SBK-DFD, SBK-DFD-U > SBK-DF, SBK-DF-U > BK-TAC, EK-TAC > AK, BK, EK, LK

    • For heavy-duty machine tool applications, choose SBK or SBK-U types.

    • For engraving machines or small machining centers, BK-TAC and EK-TAC are recommended.

    • For automation equipment, use BK, BK-E, EK, EK-E, LK, or AK, and for the support end, use BF, EF, LF, or LFA.

    • When the length-to-diameter ratio of the rotating screw exceeds 50, it is also recommended to use the same bearing block type on both ends and adopt a double-tension configuration.