Ground recirculating ball screws are obtained from extremely precise grinding techniques. However, the distinguishing feature of B.B. brand products is their “Gothic Arch” profile, a particular rolling track profile designed to optimise contact pressure occurring between ball and screw tracks as well as axial load capacity.
This profile is made up of two symmetrical arches which have a bend radius that is larger than that of the balls themselves. These arches meet on the axis of symmetry, forming a point; the two arches are related to the ball radius in such a way as to produce an optimum contact angle. This solution definitively prevents ball slippage or wedging.
Another distinctive characteristic is the type of nut used for ground screws, which B.B. supplies in two versions: double preloaded nut and single preloaded nut.