RU2270734C1 - Flush-headed bolts forming method - Google Patents

Abstract

FIELD: plastic working of metals, possibly manufacture of flush-headed bolts with riffled rod and head with flat in cold upsetting automatic machine.

SUBSTANCE: method comprises steps of reducing rod for forming thread in first position; preliminarily shaping head at forming flat in second position; finally forming head and flat in next position; forming riffles on smooth portion of rod and knurling thread.

EFFECT: manufacture of the whole flush-headed bolt in the same equipment according to advanced fin-free procedure of upsetting without cutting off part of bolt head.

1 dwg

Description

The invention relates to the processing of metals by pressure can be used in the manufacture of rod products such as embedded bolts with flat on cold heading machines.

A known method of stamping bolts with a multifaceted head, including pre-molding on the original cylindrical billet of the head with a profiled side surface and final molding of the head, carried out in the cold state of the workpiece (USSR author's certificate No. 1402405, class B 21 K 1/46, 1988) .

The disadvantage of this method is the possibility of loss of stability of the workpiece in the process of forming the head, since a forming tool of a special design is required.

There is also known a method of manufacturing bolts with a hex head, including cutting a workpiece, reducing a threaded rod, a set of heads, upsetting corrugations and knurling (Japan Patent No. 10277691, 21 K 1/46, 1998).

The disadvantage of this method is to obtain only one separate part, also to obtain a hexagon on the head.

The basis of the invention is the task of manufacturing embedded bolts, without trimming part of the bolt head, using a trouble-free landing, with corrugations under the head and thread rolling on the same equipment.

The problem is solved in that, in the method of manufacturing embedded bolts containing a rod with corrugations and a head with a flat, including reducing the rod under the thread in the first position, the formation of the head in the second and subsequent positions, obtaining corrugations on the rod and rolling of the thread, according to the invention on the second positions pre-set the head to obtain a flat, and at the next position - the final molding of the head and flats, after which they get corrugations on the rod.

The invention is illustrated in the drawing, which shows the technological process of a flawless landing of embedded bolts.

The method is as follows.

Cut the workpiece. In the first position, the reduction of the rod under the thread occurs. In the second position, a preliminary set of heads with obtaining a flat. In the third position, the final forming of the head and flat is carried out. In the fourth position, corrugation is obtained on the smooth part of the rod in the matrix. In the fifth position, the thread is rolled.

The proposed method allows the manufacture of embedded bolts without trimming part of the bolt head, using a progressive, trouble-free landing, also using this technology of grooving under the head and thread rolling is performed on the same equipment.

Claims (1)

A method of manufacturing embedded bolts containing a rod with corrugations and a head with a flat, including reducing the rod for threading in the first position, forming a head in the second and subsequent positions, obtaining corrugations on the rod and rolling the thread, while in the second position a preliminary set of heads is made to obtain flats, and in the subsequent position - the final molding of the head and flats, after which they get corrugations on the rod.