RU2278764C1 - Method for extruding unlimited length products from melt metal - Google Patents

Abstract

FIELD: production of articles by extrusion in combination with casting.

SUBSTANCE: method comprises steps of using extrusion container in one end of which die is mounted and in other end extruding ram with diameter less than that of container is mounted; casting metal into container; extruding ingot after its crystallization by means of ram at removing remainder of blank and forming gap between ram and container of press-jacket. In said jacket all surface flaws of ingot are concentrated. Then new doze of metal is cast into container and the last is welded with remainder of blank at crystallization. Press-jacket is melt by action of new doze of metal and ingot is extruded into the same product. Such operations are repeated depending upon desired length of product.

EFFECT: lowered quantity of circulating metal waste, improved quality of product.

7 dwg, 1 ex

Description

The invention relates to methods of pressing, combined with casting, and is intended to obtain products of a given chemical composition and length.

A known method of manufacturing long products, such as seamless pipes, rods, wire, including heating the billet-ingot, feeding it to the press container, and pressing, which ends with the remainder of the press residue in the container (N. Yermanyuk and others aluminum alloys "Edition. 2. Metallurgy, 1977)

The disadvantage of this method is the presence of recycled waste in the form of press residues with a thickness of 20 to 50 mm., Which is 5-15% of the weight of the workpiece. The length of the product is limited by the dimensions of the ingot, which depend on the magnitude of the pressing force.

An analogue to the claimed method is a continuous method of extruding profiles of rods, pipes and wire billets of non-ferrous metals and alloys of stamping (pressing) from liquid metal, including pouring liquid metal (see copyright certificate of F.V. Tulyankin SU 128436).

This method of continuous pressing of finished ingots without the use of liquid melt and, accordingly, without combining with casting.

Since 1948, it has not been widely used due to its shortcomings - pressing without a press shirt, it is impossible to remove it structurally, surface defects of the ingot pass into the product and welding of the press residue with the subsequent ingot occurs only due to pressure.

Therefore, it is possible to extrude products whose requirements imply the possibility of welding them and only with a low surface quality, since all surface defects of the hardening metal pass into the product.

Or press previously turned ingots, which requires an additional cycle of work, significantly increasing costs.

Also an analogue to the claimed method is the Japanese method (see patent JP 63199016). The difference between this method and the claimed one is the separation of the crystallizable melt into two chambers. Here, semi-solidified metal from another chamber is fed into the pressing chamber. Thus, during pressing, the liquid phase is almost eliminated. Accordingly, during subsequent pressing, only the end walls are welded, and washing with molten melt and a more durable connection of the pressed portions into the product does not occur. Given that the main crystallization process does not occur in the pressing chamber, but in a separate chamber, there is no possibility to press with a press jacket.

Surface defects formed both in the first chamber and in the direct pressing chamber will pass to the surface of the product and partially disperse over its cross section, significantly reducing the quality of the profile. Surface defects are not contemplated here. The presence of surface defects passes into the final product and seriously degrades the quality up to its unsuitability. Due to pressing with defects, the method cannot be widely used.

The closest analogue to the claimed method is the Ignatov method of manufacturing profiles (see patent RU No. 1557774), differs from the proposed one in that its main purpose is to utilize the heat of the poured metal to heat the gas used during extrusion. The melt is poured through the hole, at the same time intended for the location of the press matrix. It is impossible to fill in a new portion of metal until you remove the press matrix with the press residue. Therefore, in this way it is impossible to obtain welding of the melt to be poured with a press residue, and it is therefore impossible to obtain a product of a greater length. The scheme does not have a mechanism for removing press residue and there is no mention of what it should be. After the melt solidifies at the metal - container interface, defects will inevitably form, which, when pressed, completely pass to the surface of the extruded profile.

When introducing the Ignatov method, it is inevitable to obtain a profile with surface defects and a highly developed press-up due to the fact that the press residue is not provided in the cycle, as a result, a central press-up, that is, the formation of voids in the center of the product, is inevitable, which makes it unusable.

As a result, this method for pressing metals is of little use.

The objective of the invention is to obtain products of any desired length and reduce recycled waste, as well as improving the quality of the product by solving the problem of the formation of surface defects.

The problem is solved in that in the pressing method, which includes pouring liquid metal into a container and crystallizing it with the formation of an ingot, use a container with a sleeve, a die is installed to one end of the die before being filled, and a press stamp is pressed to the other, after the ingot is formed, it is pressed into the product using a press stamp, leaving a press residue, then the press stamp is again taken to the end face of the sleeve and a new portion of the liquid metal is poured, crystallization is carried out by welding this portion of the liquid metal with tavshimsya from the previous molding press remainder into a single ingot and then pressing it into the same product.

For the necessary improvement of the surface quality of the product, pressing is performed by a stamp with a smaller diameter than the container. As a result, a press shirt is formed in which all defects of the ingot remain at the border of the ingot - container. The press shirt is then not removed and when the next portion of the liquid metal is poured, it melts to form new defects during crystallization.

Pressing operations are repeated depending on the desired length of the product.

Figure 1 shows a longitudinal section of a device for implementing the method; in FIG. 2 - view "A" in figure 1; figure 3 is a view of "B" in figure 1.

The device for implementing the method comprises a container 1 with a sleeve 2, a die 3, a press stamp 4 with a press washer 5, a gate attachment 6 and a gate channel 7. In Fig. 1, the positions 8, 9 and 10 denote the press residue, liquid metal, respectively and the resulting product. From the side of the matrix, it is advisable to bore the container sleeve onto the cone by 2-3 degrees. The depth of the cone bore should not exceed the thickness of the press residue left during pressing. The depth of the cone bore should not exceed the thickness of the residue.

An example implementation of the method.

The press stamp 4 with the press washer 5 attached to it is exposed on one end of the sleeve 2, the matrix 3 is adjacent to the other end, thereby clogging the cylindrical space of the sleeve 2 with the formation of a cavity. A gating attachment 6 is pushed onto the press stamp and pressed against the gating channel 7. Liquid metal is poured into the cavity formed. When it crystallizes with a press stamp, if necessary, the resulting ingot is pressed to such a distance that it does not completely block the gate channel to eliminate air and shrink shells.

After complete crystallization of the ingot, it is pressed with a press stamp, not reaching the conical part of the sleeve, leaving a press residue and a press shirt. The conical part does not allow the stamp during the reverse stroke after pressing to entrain the press remainder. In this case, the press residue is ejected freely towards the matrix. Then the press stamp 4 is removed from the container, the gating attachment is removed and it is freed from the solidified metal. Further, operations can be repeated an unlimited number of times, as necessary to obtain a product of any length. This ensures that products of infinite length are obtained. In this case, each filled portion of the molten metal undermines the wall of the press residue remaining from the previous pressing, and melts the press shirt. The crystallizing ingot is sintered with a press residue. During subsequent pressing, the sintering site expires into the die of the matrix, stretching along the length of the pressed product and forming a single whole.

This is seen in FIGS. 4-7. The designations of FIG. 4 are also valid for FIGS. 5-7. Each of the figures shows the position of the pressed ingot and the press residue. Press shirt not shown. The press stamp 5 with the press washer 6 presses on the crystallized ingot 7 and it is finally welded with the press residue 2 along line 9.

With further pressing, the metal of the central zone will be ahead of the peripheral metal, as shown in FIG. (Yermanyuk N.Z. et al. “Extrusion of profiles from aluminum alloys”, ed. 2. Metallurgy 1977, pp. 64-70). After complete pressing of the metal, the welding line is dispersed and almost completely disappears.

With existing welding methods, the product is butt welded, as shown in Fig. 7. The welding line is clearly visible here and the crystal structure is broken near it.

After the required number of compacts, the press residue is removed in the traditional way. The board is pushed back, which presses the matrix to the container (not shown) and the press stamp pushes the press residue together with the matrix. Then the press residue is cut from the matrix.

The claimed method can achieve the following technical result. Get the product (pipe, bar, wire, profile, etc.) of any length. Along the way, eliminate the disadvantages of the previous analogues in order to introduce the inventive method into mass production. Significantly reduce metal waste. To reduce energy costs for the production of products by pressing.

Claims (1)

A method of extruding articles of unlimited length from a liquid metal, including pouring liquid metal into a container and crystallizing it to form an ingot, characterized in that they use a container with a sleeve, a die is installed at one end of it before pouring, and a smaller diameter press stamp is applied to the other, than a container, to form a gap in which metal can remain during pressing, after the ingot is formed, it is pressed into the product using a press stamp, leaving a press residue and a press shirt, then the press piece the mpel is again taken to the end of the sleeve and a portion of the molten metal is poured, the press shirt is melted by it, crystallization is carried out with welding of this portion of the molten metal with the remainder from the previous pressing of the press residue into a single ingot and subsequent pressing of the ingot into the product, then the operations are repeated as many times as necessary .

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