SCREW PILE Russian patent published in 2011 - IPC E02D5/56 

FIELD: construction.

SUBSTANCE: screw hollow shaft is made along the perimeter in the form of a multiple helical surface with screw grooves inside and outside of the screw hollow shaft at the angle of 30°-55° to its axis of rotation in the form of pockets of curvilinear shape with centres of curvature of curvilinear pockets on the helical surface arranged in turns outside and inside the cross section of the screw hollow shaft, is mounted from one strip of identical width, coiled into cylindrical turns, connected to each other along longitudinal edges, and the strip is bent in a wave-like manner along bending lines arranged at the angle to its longitudinal edges, to form helical surfaces along outer and inner surfaces directed to one and the same side at the angle of 30°-55° to the axis of rotation of the screw hollow shaft, as pockets of curvilinear shape along outer and inner surfaces, which along the perimetre of the screw hollow shaft may be different not only in shape, but also in dimensions, at the same time the distance between bending lines is equal to the sum of length of perimetres of geometric figures of pockets of inner and outer surfaces.

EFFECT: expansion of functional capabilities.

1 cl, 6 dwg