SU1731398A1 - Tool complete set for manufacture of hollow blanks of axisymmetric articles - Google Patents

Abstract

Use: for making blanks of axisymmetric products such as railway wheels and solid-rolled rings. SUMMARY OF THE INVENTION: The tool kit comprises an upper with a central opening and lower sedimentary plates. Between them there is a calibration ring. A punch is installed in the central hole of the upper sedimentary plate. On the surface of the lower sedimentary plate, at its center, a boss is made in the form of a truncated cone with a height of 0.1-0.3 punch diameter and upper base diameter equal to 0.9-0.98 punch diameter. The angle of inclination of its generatrix is determined by the recommended limits. In the process of flashing the through hole, the cutting edge of the piercing falls on the tapered part of the cavity formed during the draft of the workpiece on the bottom plate with the boss. As a result, the jumper is removed without burrs, which improves quality and reduces metal consumption. 3 il. WITH S

Description

The invention relates to the processing of metals by pressure, in particular, to a tool for deforming pressing equipment, and is intended for the manufacture of workpieces of axisymmetric products such as railway wheels and solid rolled rings.

The purpose of the invention is to improve the quality of the blanks and reduce the consumption of metal by reducing the size of the burr on the inner surface of the blanks and reducing the allowance for mechanical treatment of the inner surface of the finished products.

Figure 1 shows the tool kit at the time of precipitation of the workpiece; figure 2 - tool kit during the distillation of the workpiece; fig. 3 shows the operation of obtaining a through hole in the workpiece.

A tool kit for making semi-symmetrical workpieces contains an upper sedimentary plate 1 with a central hole in which a punch 2 is installed, a calibration ring 3 and a lower sedimentary plate 4.

On the bottom plate, a boss 5 is made in the form of a truncated cone of height h (0.1 ... 0.3) d, with a diameter of the upper base eh (0.9 ... 0.98) d and the angle of inclination of its generatrix a, lying within

m ° (rdToYa + D. where d is the diameter of the punch;

Ad is the displacement of the punch and boss axes

VI

CJ 00

about

00

The toolkit also contains a lower piercing plate b for forming a through-hole and piercing 7.

The technology for producing blanks for axially symmetric products using a tool kit is as follows.

Having heated to the deformation temperature, the initial billet 8 is laid on the upper base of the boss and centered with a special centering device

A billet sediment is produced between the sediment plates by the force of the main traverse of the press (not shown in the figures) until the calibration ring stops against the lower sediment plate. Not removing the force from the main traverse of the press, the metal is distilled by the punch before filling the stamping brook formed by the deformation tool. Then the billet is transferred to the piercing press, centered. The firmware 7 is lowered into the cavity of the workpiece, the penetration of the punch 2 is obtained, and by further movement it flushes the jumper. In this case, since the diameter of the smaller base of the lower cavity of the workpiece is smaller than the diameter of the piercing (the diameter of the piercing is equal to the diameter of the punch), the cutting edge of the piercing falls on the tapered part of the lower cavity of the workpiece and the jumper metal detachment occurs without any significant burrs. The diameter of the smaller base of the conical lower cavity of the workpiece, equal to 0.9-0.98 of the punch diameter, determined the outcome of the practical possible accuracy of centering the workpieces relative to the piercing before the piercing and the diameter of the punch. In practice, the accuracy of the centering is in the range from 1 to 5 mm. The diameter of the punch ranges from 100 to 300 mm. In this case, with the firmware, the cutting edge of the firmware is guaranteed to be in the zone of the conical part of the lower cavity of the workpiece.

The minimum angle of inclination of the forming truncated cone is defined as follows. The bosses were made with a taper angle of 20, 25, 30, 35, 40 and 45 °, 25 mm high and a smaller base of 235 mm. With their use, rings were made with dimensions DH x dBH x H 1000 x 800 x 100 mm. The punch diameter was 250 mm. Experiments have shown that when the taper angle is less than 30 °, compression of the inner surface of the workpiece with the inner roller of the ring-rolling mill leads to the formation of intense local broadening in the form of a metal overflow onto the tapered surface, which then forms a fold and leads to a deep sunset. The upper value of the angle of inclination of the generatrix should be limited to

(0.1 ... 0.3) 0

a arctg

otherwise

(0.05 ... 0.01) d + Ad diameter of the larger base of the lug does not exceed the diameter of the punch, with the result that the cutting edge of the latter at the end of the firmware goes beyond the conical part of the hole of the workpiece,

When the height of the boss is less than 0.1 of the punch diameter, the area of cutting of the metal by the punch approaches the lower end surface of the workpiece and leads to the formation of the same burr as when piercing the workpiece with a flat bottom end surface.

When the height of the boss is more than 0.3 of the punch diameter, the probability of getting a piece (non-filling of the tapered part of the inner bore) on the ring products of a small bar appears, which requires an increase in the machining allowance.

The use of a tool kit for the manufacture of workpieces of axisymmetric products reduces the expenditure ratio of the metal in the manufacture of finished products from them by reducing the allowance for mechanical processing of their inner surface, as well as improving the quality of the blanks by reducing the burr size along their inner surface,

Claims (1)

Invention Formula A tool kit for the manufacture of hollow billets of axisymmetric products, comprising an upper with a central hole and lower sedimentary plates, a calibration ring and a punch between them, mounted in the axial opening of the upper plate, characterized in that, in order to improve the quality of the blanks and reduce the metal consumption, The working surface of the lower sedimentary plate is made of a central boss in the form of a truncated cone with a height of (0.1 ... 0.3) d, a diameter of the upper base (0.9 ... 0.98) d and an angle of inclination of its generatrix, which are defined within the 30, „W - .. WU (0.05 ... 0.01) d + Ad where d is the diameter of the punch; Ad is the amount of displacement of the punch and boss axes. Fig.Z