RU2532624C1 - Hot forging of semis from cylindrical billets - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to blank production and can be used in press shop in production of semis. Capsule has cylindrical wall and flat bottoms to accommodate cylindrical blank is fitted in container pass through bore. Container is secured at press bend. Through hole length part features diameter D_"б" corresponding to capsule wall OD. Axial force is applied by pressure male die with diameter D_M corresponding to ID of capsule wall ID via one of capsule bottoms. Note here that said blank thrusts via second bottom against support male die secured to the bed. Container pass bore on side facing the pressure male dia on length remainder features diameter D_M. Said capsule is arranged in said through bore with axial clearance between the side of first bottom facing the pressure male die and pass part of diameter D_M. Clearance magnitude is defined by cited relationship subject to blank height.

EFFECT: higher quality of semis.

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Description

The present invention relates to procurement and can be used in forging shops of metallurgical and engineering plants.

There is a method of hot pressing a semi-finished product from a workpiece, the latter being mounted in a capsule. Such a method is often used to increase the density of pre-pressed (or sintered) billets of metal alloy powders, to pressure treat metal castings to remove internal discontinuities formed during their solidification, etc. (see A. Prokhorov. Isostatic for cold and hot pressing of products, p. 5, publ. 02/11/2013 - Internet address: http // www / ruscastings.ru / work / 168/5617/5664/6636).

This method provides high quality semi-finished products and allows you to bring their properties closer to semi-finished products obtained using deformation technologies.

The disadvantage of this method is the difficulty of ensuring the uniformity of the properties of the resulting semi-finished products throughout their volume.

A known method of hot pressing a semi-finished product from a cylindrical billet, the latter being mounted in a metal capsule with a cylindrical wall and flat bottoms, comprising placing the capsule in the through hole of the container stream mounted on the press frame, and this hole is made with a diametric dimension corresponding to the length part the outer diameter of the cylindrical wall of the capsule, and an axial force is applied to the workpiece by a pressure punch with diametric dimensions corresponding to them to the inner diameter of the cylindrical wall of the capsule, through one of the said bottoms with its support through the second of the said bottoms on the support punch mounted on the press frame (see US patent No. 7037466, CL 419/48, published in 2006 - prototype) .

The disadvantage of this method is the irrational deformation scheme that does not provide "study" of the Central zone of the semi-finished product.

The proposed method of hot pressing a semi-finished product from a cylindrical billet mounted in a metal capsule with a cylindrical wall and flat bottoms, includes placing the capsule in the through hole of the container stream. On a part of the length, this hole is made with diameters D _b corresponding to the outer diameter of the cylindrical wall of the capsule. An axial force P _os is applied to the workpiece by a pressure punch with diameters D _m corresponding to the inner diameter of the cylindrical wall of the capsule, through one of the said bottoms with its support through the second of the said bottoms, onto a supporting punch fixed to the press frame.

On the container side, facing the pressure punch, on the rest of the length, the mentioned hole of the stream is made with diameters D _m corresponding to the inner diameter of the cylindrical wall of the capsule; the capsule is mounted in the container with an axial clearance Δ between the side of the first of the bottoms facing the pressure punch and the part the mentioned hole of the stream with a diametrical dimension of D _m The size of this gap is determined by the dependence

Δ = (0.02 ÷ 0.12) N,

where Δ and H are, respectively, the size of the aforementioned gap and the height of the workpiece before applying the force P _os to the workpiece.

The proposed method differs from the prototype method in that on the remaining part of the length, the said hole of the stream is made with diametric dimensions D _m corresponding to the inner diameter of the cylindrical wall of the capsule on the container side facing the presser, the capsule is mounted in a container with an axial clearance Δ between the facing to the pressure punch by the side of the first of the said bottoms and part of the said hole of the stream with diameters D _m , the size of this gap being determined by the dependence

Δ = (0.02 ÷ 0.12) N,

where Δ and H are, respectively, the size of the aforementioned gap and the height of the workpiece before applying the force P _os to the workpiece.

The technical result of the use of the invention is that by optimizing the “study” of the central zone of the semi-finished product and streamlining the deformation scheme, a high-quality semi-finished product is obtained.

The invention is illustrated by drawings, where in Fig. 1 is a capsule with a workpiece before hot pressing;

Fig. 2 schematically shows the experimental stamp in the initial position (before hot pressing);

Fig. 3 - the same, at the time of sampling the gap Δ;

Fig. 4 - the same in the final position (completion of hot pressing).

The invention is illustrated by examples of the method of hot pressing of a semi-finished product on experimental dies.

Example 1. A preliminarily prepared blank 1 (Fig. 1) from a “powder” of VT6 titanium alloy pressed to a density of 0.6 of the density of a solid material is placed in a steel capsule consisting of a cylindrical wall 2 and two bottoms 3 and 4 welded into it which is then degassed and sealed. The dimensions of the workpiece are ⌀120 mm with a height of H = 160 mm. The experimental stamp (Fig. 2) includes a heated container 5, mounted on the bed 6 of the press. A stream is made in the container in the form of a through circular hole, a length part 7 of which has diametrical dimensions D _b corresponding to the outer diameter of the cylindrical wall 2 of the capsule. Part 8 of this hole is made with diameters D _m corresponding to the inner diameter of the wall 2 of the capsule. The capsule with the workpiece is heated and mounted in part 7 of the opening of the container stream on the support punch 9, mounted on the bed 6 of the press. In part 8 of the creek opening, a pressure punch 10 is placed. Between the side 11 of the bottom 3 facing the punch 10 and part 8 of the creek opening, a gap Δ is provided. The gap A in the experiment is selected in the range Δ = (5 ÷ 7) mm.

An axial force P _os (Fig. 3) is applied to the workpiece 1 through the bottom 3 by means of a pressure punch 10 and supported through the bottom 4 onto the support punch 9. The workpiece 1 settles. In this case, the cylindrical wall 2 of the capsule is extruded in the opposite direction to the force P _os , and after sampling the gap Δ, the extrusion process of the wall 2 is terminated, the workpiece is pressed under full compression.

At the final stage of the process (Fig. 4), the support punch 9 is pressed into the wall 2 of the capsule, and the part 12 of the wall 2 adjacent to this punch is extruded into the part 7 of the opening of the container stream. With the emphasis of the punch 10 in the container 5, the pressing process ends. Then the capsule is removed from the container (not shown). By mechanical processing, for example, the steel capsule is separated from the finished semi-finished product.

The finished semi-finished product has a density of 0.98 ÷ 0.99 of the density of the continuous material.

Example 2. A pre-prepared blank 1 (Fig. 1) in the form of casting from aluminum alloy 1420 is placed in a steel capsule as in Example 1. The dimensions of the blank are ⌀170 mm; H = 200 mm.

Hot pressing is carried out as in example 1.

The finished semi-finished product has no internal discontinuities, such as porosity, internal shrinkage, and interdendritic cracks that formed during the solidification of the casting. Increases ductility and cyclic strength.

Thus, the proposed method allows the economical production of high-quality semi-finished products. Of particular importance is the method in the production of structural elements of modern aircraft.

Claims (1)

A method of producing a semi-finished product by hot pressing of a cylindrical billet placed in a metal capsule with a cylindrical wall and flat bottoms, comprising placing the capsule with the billet in the through hole of the container stream fixed to the press bed, and said through hole with a diameter D _b corresponding to a part of the length corresponding to the outer diameter of the cylindrical wall of the capsule, the application to the workpiece axial force P _OS pressure punch with a diameter of D _m corresponding to the inner diameter the cylindrical wall of the capsule, through one of the bottoms of the capsule with the support of the workpiece through the second bottom to a support punch fixed to the press bed, characterized in that a container is used, the through hole of the stream from the side facing the pressure punch, on the remaining part of the length is made with a diameter D _m, a capsule with the workpiece disposed in the through hole of the container stream axial gap Δ between the pressing punch facing the side of said first bottoms stream and a portion of the through-holes with a diameter D _m, when e Δ nd value of the gap determine the dependence of Δ = (0,02 ÷ 0,12) H, where H - the height of the workpiece prior to application of a force thereto F _oc.

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