SU912404A1 - Apparatus for cutting tubes - Google Patents

Description

(54) PIPE CUTTING DEVICE

one

The invention relates to the processing of metals by pressure and can be used in mechanical engineering for cutting pipes.

It is known a device for cutting pipes, having, kinematically connected with a drive of a reciprocating movement, two knives having cuts with cutting edges located at an angle of one to the other 1.

A disadvantage of the known device is that the cutting is carried out by limited areas of the knives, which leads to uneven wear of the cutting edges and, accordingly, the durability of the knives decreases.

The purpose of the invention is to increase the stability of knives.

The goal is achieved by the fact that in a pipe cutting device containing kinematically associated with the drive of the reciprocating movement of two, 0 knife, having cutouts with cutting edges at an angle to one another, the tops of the corners of the cut of each of the blades are mutually offset from the axis devices by an amount equal to 4-TtdCos A.,

and the cutting edges of each knife are located at a right angle to one another, while one of the edges of each knife is made flat and the other is inclined to the axis of the device at an angle d determined by the following dependence arctg (l-). where - the smallest diameter of the pipe being processed;

D - the largest diameter of the processed pipe.

FIG. 1 image f eco device, general view; in fig. 2 - the same plan view; in fig. 3 - design scheme.

The device for cutting pipes contains knives 2 mounted in guides .1, each of which is made with notch 3 in the form of an internal right angle, the tops of which are displaced by an amount. cUCosd-, which contributes to the overlapping of the cutting edges when cutting. The amount of displacement is determined by the minimum diameter of the pipe being processed (Fig. 3). The cutting edges 4 are made flat, and the cutting edges 5 are pointed and inclined to the device axis at an angle.

o (arctg (1- -f)

This angle is determined by calculation from the condition of ensuring that the pipe is centered with a maximum diameter D while all the edges of the knives are in contact with the pipe. If this condition is not observed, the tube will move towards the absence of contact and the cut will be oblique. The second condition accepted in the calculation is that the pipe of minimum diameter should not be displaced relative to the axis of symmetry of the device. Otherwise, the pipe may shift along the cutting edges of the knives during final compression, which degrades the quality of the cut.

The device works as follows.

From the reciprocating drive (not shown), the knives 2 move towards each other, with the pipe 6 being picked up by the edges 4 and 5 of the knives 2, centered, compressed and cut. Then the knives 2 are returned to their original position.

The device makes it possible to increase the durability of the blades by uniformly distributing the loads along the cutting edge.

Claims (1)

1. The patent of France No. 2144937, cl. In 23 D 21/00, 1973 (prototype). Mti Tpt / / fffФaf