METHOD FOR MANUFACTURING TERMINAL BOLTS Russian patent published in 2021 - IPC B21K1/46 B21K7/10 

FIELD: metal processing.

SUBSTANCE: invention relates to the processing of metals by pressure and can be used in the manufacture of terminal bolts for rail fasteners of railway tracks. The preliminary formation of the bolt head and its spherical support surface is carried out. The head is given the shape of a rectangle having the size of the side (0.7-0.9)S, where S is the larger or smaller side of the finally formed rectangular head. Preliminary formation is carried out in a floating punch with a pusher in the form of a wedge at the end. At the same time, they give the head from the side of the smaller face the shape of a truncated prism with an angle of 4-15°. Then, the rectangular head and the spherical support surface are sequentially calibrated simultaneously with the reduction of the rod under the thread rolling and the formation of a chamfer at its end.

EFFECT: invention ensures the possibility of evenly distribution of the load on the cold-upsetting tool and, consequently, a favorable flow of metal and the formation of a product of the required shape and size.

1 cl, 6 dwg