New SKF long lead ball screws with a rotating nut design provide precise positioning and offer compact, ready-to-use, solutions for linear-actuation applications requiring high-speeds and long strokes. Their design allows the drive motor to move with the nut to reduce inertia. It also requires less power and achieves linear speeds up to 110 m/min.
Unlike traditional ball screws with rotating screw shafts, these integrate a nut rotating inside the bearings and along the fixed long-lead screw shaft. The motor moving with the nut minimizes the inertia and critical speed problems, typically associated with long rotating screw shafts, and promotes optimized performance.
Design features include angular contact bearings directly mounted on the nut and preloaded in a "O" configuration to fully support the torque generated by the belt tension; a fixed screw shaft to allow for simplified mounting; two all-metal seals to protect the support bearings and nut from contaminants; and brush wipers mounted in the ball screw in standard configuration
for additional protection.
These ball screws are available with a rotating nut with axial play (Series SLT) or with backlash elimination (Series BLT). Diameters range from 25 mm to 50 mm and leads range from 20 mm to 50 mm.