RU1773543C - Radial forging tool - Google Patents

Abstract

SUMMARY OF THE INVENTION: a tool for radial forging consists of strikers, on the working surface of which, formed by the inlet and gauge sections, a recess is made. The recess is located at the interface between the inlet and gauge sections. One of the two open sides of the recess is made from the entrance area. The side opposite to it extends to the gage section with its face. The depth of the excavation is equal to the magnitude of the working stroke of the tool. 1 C.p. f-ls, 2 ill.

Description

The invention relates to the processing of metals by pressure, namely, to deformation of workpieces on radial forging machines (RCMs) and can be used in forge-and-press shops of machine-building plants.

A known tool for radial forging, adopted as a prototype, in the calibrating section of which, from the side opposite to the entry section along the axis of symmetry of the tool, a recess is made open from its two adjacent sides, two other adjacent sides of which form faces on the calibrating section, respectively its wide and narrow parts.

The use of these dies for radial forging allows the formation of helical protrusions and their compression in one pass, which does not fully provide a sufficient requirement for the quality of the metal in the axial zone of the forging. This is explained by the fact that the protrusions formed on the workpiece during their subsequent deformation by the calibrating section of the striker do not allow creating sufficient conditions for

penetration of deformation into the central areas of the forging.

The aim of the invention is to improve the quality of the metal forgings in the axial zone.

To achieve this goal, the proposed technical solution uses a tool for radial forging, the cutout on which is made not from the calibrating section, but from the entry section of the striker, and the depth of each striker is equal to the working stroke of the RCM.

The invention is illustrated in FIG. 1 and 2,

In FIG. 1 shows a radial forging hammer, general view. In this case, the cutout is made both on the calibrating section and on the section of the inlet cone, the calibrating part of the striker consists of two sections - wide 1 and narrow 2, which are adjacent to each other, while I c is the length of the wide section of the calibrating part of the striker, h - the length of the narrow section of the calibrating part of the striker. The width of the narrow section of the calibrating part of the striker is 50% of the width of the calibrating part, i.e. one of the side surfaces of a narrow section of the calibrating part faces along its longitudinal axis

cl

with

VI VI

CA)

SL

4 gj

the symmetry of boycé. The length of the cut at the inlet of the striker li is interconnected with the angle of the inlet cone and the stroke of the striker with the following expression

H htg ",

where N is the depth of cut or working stroke of the RCM;

a-angle of inclination of the lead part of the striker.

The lateral sides of the recess are located obliquely to its bottom and have an inclination angle of 25-45 °. When this angle is selected on the strikers of less than 25, the maximum single reduction at the point of transition from the bottom of the notch to the calibrating section is sharply reduced and, for example, at an inclination angle of 13 ° and a feed rate of 20 mm / s it will be 3.6 mm. Increasing the angle above 45 ° can lead to the formation of clamps on the outer surface of the forgings.

The tool works as follows (Fig. 2).

In a circular cross-section, the workpiece is crimped simultaneously by four strikers, which have cutouts at the entry and gauge sections. In this case, four helical protrusions are formed with a height equal to the depth of the cutout N. The height of the protrusions H is formed gradually from the inlet to the calibrating section and gains its maximum equal to the working stroke of the RCM, in front of the wide section of the calibrating part of the striker.

When forged by the prototype method, deformation of the workpiece is first carried out by the inlet and gauge parts of the striker and only then protrusions of height d begin to form, followed by compression in a narrow section of the gauge part of the striker.

Thus, the value of a single compression of the helical protrusions of the proposed tool in comparison with the crimps in the prototype tool will be K times larger and determined by the formula

K I7d

The depth of the recess H is chosen equal to the magnitude of the stroke. If the depth of the recess H at the inlet and calibrating parts of the striker will be greater than the working stroke of the RCM, then after the formation of the helical protrusion, it is not possible to feed the workpiece in the longitudinal direction, since the diameter of the workpiece along the protrusions will be greater than the distance between the pairwise opposite wide parts of the calibrating section brisk. If the height H of the helical protrusions, which is associated with the depth of the cut, is less than the working stroke of the RCM, then the degree of deformation of the protrusions will be insufficient to work out the axial zone of the forging. Therefore, the depth of cut on the strikers is taken equal to H, the working stroke of the RCM.

Example. Ingot weighing 2600 kg,

with an outer diameter of 570x520 mm made of steel 38KHNZMFA heated to a temperature of 1160 ° C, they were forged by strikers having a cutout from the entry area with a depth equal to the working input of the RCM, on a machine with a force of 10 MN (model SXP-55). The lateral edges of the tool are made with an inclination angle of 30 °.

After forging, samples were cut from forgings for mechanical tests in the radial direction. The mechanical properties of the metal obtained by the proposed tool:

Ukova coefficient 2.5 a, MPa1166

0v, MPa1215

d,% 13.0

% 55.0

KCU, kJ / m2715

A similar ingot weighing 2600 kg was forged according to the prototype method in strikers having cutouts on the opposite side of the entry section. Then, radial samples were also cut from the obtained forgings. Mechanical properties of the metal obtained by the prototype method Uklov coefficient 2.5 From, MPa1127

SVG, MPa1205

5% 12.5

$% 46.0

KCU, kJ / m2479

When forged on a radial forging machine in strikers having a cutout on a gauge section on the opposite side of the entry section, prototype forging, deformation of the same section of the workpiece are performed with crimps dg in one stroke, interrelated with the longitudinal feed rate and angle slope of the entry section of the striker. Then, in this case, the value of a single reduction in one stroke of the striker is determined by the expression

V

0 02 - tgo, (1)

where dg is a single compression;

V is the feed rate;

p is the number of reductions;

and - the angle of the entry part of the striker. 5 Thus, the value of a single reduction in the prototype tool will be

equal to 62 - 1.38 mm.

V-60

P

 tga

20-60 200

tg13c

If there is a cutout at the input and calibrating parts of similar strikers equal to the working stroke (for RCM SXP-55 N 15 mm), the single reduction will be (3i 15 mm. Therefore, when forging in the proposed tool, the magnitude of the single compression of the protrusions will be larger in 11 times, where 6g is the value of a single crimp when using the prototype tool, 5i is the value of a single crimp by the proposed tool.

The data on the increase in single reduction during forging by the proposed tool are consistent with an increase in the mechanical characteristics of the metal, half of the screen during testing. Thus, the relative narrowing increases by 20%, and impact strength by 47%.

Claims (2)

1. A radial forging tool, consisting of strikers, a recess is made on the working surface of each of which is formed by the return and gauge sections, located along the symmetry axis of the tool, formed by the faces of its two adjacent sides, which divide the gauge section, respectively on its wide and narrow parts, and is open on the side of two other adjacent sides, characterized in that, in order to improve the quality of the forgings due to the intensification of the processing of metal in the axial zone of the forging, the recess is made in the place filar stress and sizing portions, wherein one of the open sides of the recesses formed by the lead-in area, another side opposite to it, on its face leaves the gauge portion, and recess depth of each striker equal to the working stroke of the tool. 2. The tool according to claim 1, characterized in that the edges of the recess are located obliquely to its t, well.