METHOD TO MANUFACTURE LIGHT ARCHED GIRDER Russian patent published in 2013 - IPC E04C3/08 

FIELD: construction.

SUBSTANCE: blank from a rolled section, having a solid wall and two parallel shelves, is cut along the wall. Two parts with ledges are created, in which the outer edge has larger size compared to the base. The cut blank is divided into two parts, the produced parts are shifted in the transverse direction. Each ledge of one part is connected to two ledges of the other part. Longitudinal sections of ledge edges consist of three adjacent straight sections. The middle one from the sections is parallel to shelves, and the extreme ones are arranged as the angle to it. One part of the cut blank is prepared in such a way that the shelf is bent convex to the wall. For this purpose V-shaped cuts are arranged in well ledges to the plane of the shelf. Further the shelf is bent to match edges of V-shaped cuts, and these edges are fixed. The other part of the cut blank is prepared in such a way that the shelf is bent concave to the wall. At the same time the ledges of the wall is cut in the middle to the entire height of the wall to the shelf, and cut edges are opened by means of shelf bending. Further an insert is made between these edges and connected by means of welding.

EFFECT: reduced labour intensiveness of manufacturing and assembly.

3 cl, 9 dwg