SU1204309A1 - Method of forging hollow work - Google Patents

Description

one

The invention relates to the processing of metals by pressure, namely, forging, and can be used in the preparation of hollow forgings.

The aim of the invention is to reduce the labor intensity and increase the utilization rate of metal in the manufacture of hollow forgings with convex outer and inner surfaces due to the use of the optimal shape of the semi-finished product and the profile mandrel.

Fig, 1 shows a mandrel and a semi-finished product with a central location of the protrusion, the initial position; figure 2 is the same, with the offset arrangement of the protrusion; on fig.Z - processed semi-finished product of figure 1 after rolling; in fig. 4 is the same for the semifinished product of FIG. 2; on fig.Z - semi-finished product with a stepped protrusion, the initial position; figure 6 - rolling of the semifinished product in fig.Z, the initial stage; 7 - the same, intermediate stage; in FIG. 8 - the same. Final stage: in FIG. 9 - calibration of the obtained forging; 10, the final stage.

The method is carried out as follows.

The hollow semi-finished product 1 is made with a protrusion 2 in the central part of the outer surface. At the same time, depending on the given curvature of the forging, the protrusion is arranged symmetrically to the ends (figure 1) or is shifted to one of the ends of the semi-finished product (figure 2). The semifinished product is put on a profile mandrel 3 with the length of the AOP working part 0.3 - 1.2 projection B length and 0.1 - 0.7 length of the semi-finished product L mounted on supports 4, and cut by strikers 5 by crimping the protrusion to obtain forgings 6 with external and internal surfaces (Figs 3 and 4),

In order to expand the sizes of the forgings obtained, the protrusion in the central part is made with the diameters of the benches, successively decreasing to the ends (Fig. 3), and the semi-finished product is rolled in several transitions. Prefabricated I with a protrusion of length E, consisting of steps 7 and 8, is put on the profile mandrel 3. The length of the working part of the mandrel is 0.3 - 1.2 times the length of the step 7 and is

043092

0,1 - 0,7 lengths of the semifinished product L. At first, step 7, which has a maximum size in diameter, is subjected to rolling, the total reduction on this

5 transition is equal to the height of the ledge. As a result of rolling, a billet 9c is obtained by convex outer and inner surfaces with a wall thickness of variable length (Fig. 6). After this, the mandrel 3 is shifted in the axial direction relative to the workpiece 9 so that the edge of the ledge 8 is located at the corresponding end of the working mandrel 3, taking into account the broadening

15 when rolling (Fig.7). In this position, the workpiece is rolled, after each pass around the perimeter, the working part of the mandrel is displaced in the axial direction. The total size on the deformed section is equal to the height of the step B, As a result of rolling, a forging 10 with a uniform wall thickness is obtained (Figure 8).

If it is necessary to obtain forgings that are exact in geometry, they are calibrated by rolling with a curly striker 11 on the profile mandrel 12. As a result, a forging 13 with a radius of curvature of the outer surface R is obtained.

30 (FIG. 9).

If it is necessary to obtain forgings with a small radius of curvature and relatively small hole diameters at the ends of the forging 1c

In this case, it is not possible to use rolling on the mandrel because of the impossibility of removing it from the forging cavity) a draft of the forging 13 underneath is used. figured or flat plates

0 14. At the same time, a forging 13 with a radius of curvature R is obtained (Fig. 10).

The expansion of the hollow semi-finished product with a protrusion in the central part is carried out on a mandrel with a working length

5 parts equal to 0.3-1.2 of the protrusion length and constituting 0.1-0.7 of the length of the semifinished product.

When the length of the working part of the EOP LIP mandrel is the length of the semi-fab ricata), rolling leads to the appearance of clamps and ring folds on the inner surface of the forgings and disruption of the forming of the forging. When (j 0,7 L rolling does not have

55 meaning due to the low intensity of shaping the curvature of the lateral surface. When, 3 (where & - the length of the protrusion is in violation of

The formation of forgings due to the appearance of folds on the inner surface, at an inlet of 1.2 t, redistributes metal volumes along the length of the workpiece, which leads to a low intensity of curvature formation on the lateral surface.

Example. The simulation of industrial technology was carried out on lead blanks. Sizes of preparation:

Outer diameter (main), mm Outer diameter of the protrusion, mm Length of the workpiece (L), mm

204309.

Projection length

(X) mm14.5

Internal diameter-- meter, mm 35

5 The blank is rolled out on a profile mandrel with a working length tan of 15 mm (ttftp 1.04), the diameter of the mandrel is 20 mm, the collar diameter is 34 mm. Rolling is carried out flat. After rolling and sediment get a forging with the following dimensions.

Forging length, mm 66.0 Outer maximum diameter, mm 70 Outer diameter at the ends, mm45.0

Wall thickness mm 6

ten

15

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Lg

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FIG If

5

6

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iV2.7

f / 2.

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Compiled by I. Akmulin. Editor N. Gorvat Tekhred. Father Nece. Corrector S.Cherni

Order 8459/9 Circulation 646 Subscription

VNIIPI USSR State Committee

on affairs invented and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch PPP Patent, Uzhgorod, Proektna St., 4

Fig.Yu

Claims (3)

(54) (57) 1. METHOD FOR FORGING HOLLOW FORGINGS, mainly with convex outer and concave inner surfaces, including the manufacture of a hollow semi-finished product and its subsequent rolling, characterized in that, in order to reduce the complexity of manufacturing and increase the metal utilization coefficient, the semi-finished product is made with an annular protrusion on the outer surface and rolling is carried out by compressing the protrusion on the mandrel with a length of the working part equal to 0.3 - 1.2 of the width of the protrusion and component 0.1 - 0.7 of the length of the semi-finished product. 2. The method according to π. 1, with the fact that the protrusion is performed stepwise with lowering the level of the ledges to the ends of the semi-finished product. 3. The method according to claim 2, with the fact that the rolling is carried out by sequentially compressing the ledges of the semi-finished product, starting with the step of the maximum diameter, carrying out the axial feed of the workpiece after IV after each pass perimeter. [R