UA67960A - Method for extrusion of hollow parts with shaped side - Google Patents

Abstract

The method for extrusion of hollow parts with shaped side consists in radial extrusion of the billet material into the transverse clearance between the upper matrix and lower movable support followed by subsequent change in the direction of the metal flow for the straight line along internal side ofmould, moreover the upper shaping tool is divided into half-mould and cavity-retainer plate. Lower working tool is divided into deforming anti-punch and shaping half-mould, in this case the inner diameter of lower half-mould is taken as equal to 1.05... 1.3 of diameter of the cavity of upper half-mould, the clearance length at transverse extrusion changes due to axial displacement of one of the shaping tools or their connection, the diameter of external surface of part changes due to the longitudinal travel of the cavity-retainer plate, which has surfaces of different diameters on the height.

Description

Description of the invention

The invention relates to the field of technology, namely to the processing of metals by pressure and can be used in the manufacture of hollow parts by the method of transverse extrusion.

There is a known method of radial extrusion into the gap between the working tools (anti-punch and die) followed by a change in the direction of the metal flow to an axial one along the inner side surface of the clip (peripheral part of the die). This method produces pipes whose diameter is twice the diameter of the original workpiece (1). However, this method does not allow you to obtain hollow parts with a variable wall thickness of 70, due to the constant position of the working tool (counter punch and matrix).

Also known, chosen as a prototype, is the method of manufacturing hollow parts, which consists in radially extruding the workpiece material into the transverse gap between the upper matrix and the lower movable support, followed by changing the direction of the metal flow to a straight line along the inner side surface of the matrix. To obtain parts with variable wall thickness, the size of the transverse gap during extrusion is changed due to 12 movements in the direction of the extrusion force of the solid working tool - the movable support (21.

The disadvantage of this method is the impossibility of obtaining hollow parts with a variable external profile.

This is due to the fact that the change in the direction of the metal flow from radial to straight is carried out in the "turning" zone, which has a fixed position relative to the axis of symmetry (the angle of contact of the matrix and the clamp), therefore, the constant value of the diameter of the outer cylindrical surface of the part, which is formed by the side surface of the clamp. In addition, since the change in the gap between the matrix and the movable support when the latter is moved down occurs over the entire surface of the movable support, it leads to a rigid movement under the action of the punch of the entire semi-finished product also down behind the support. This, in turn, leads to the formation of a transitional stepped area on the upper side, and not on the side of the movable support. Transferring this "step" to the inner surface in the area of the spatial bend - changing the flow direction to 907 - is accompanied by distortion of the shape and deterioration of the quality of the product. Such a defect 22 is due to the fact that the gap change is carried out over the entire contact surface of the movable support with the workpiece, which is "inadmissible.

The basis of the invention is the task of obtaining parts with a variable external profile and improving the quality of the design of internal and external contours, that is, expanding the technological capabilities of the process and improving the quality of the product. at

The problem is solved due to the fact that in the method of extruding hollow parts with a shaped side surface, the upper forming tool is divided into a half-matrix and a clamp, the lower working tool is divided into a deforming counterpunch and a forming half-matrix, while the inner diameter of the lower half-matrix is taken as equal to 1, 05...1.3 of the diameter of the cavity of the upper part of the semi-matrix, the size of the gap during transverse extrusion is changed due to the axial movement 39 of one of the forming tools or their combination, the diameter of the outer surface of the part is changed due to the longitudinal movement of the clamp, which has surfaces of different diameters by height

The change in the size of the gap due to the axial movement of the upper and lower half-matrices in relation to each other and to the counterpunch does not occur over the entire contact surface of the movable support with the workpiece (as in the prototype), but only in the peripheral part - the zone of the metal of the workpiece flowing into the transverse gap, thanks to Z 50, a transitional "step" does not form on the upper side of the flange of the workpiece, and when the direction of flow changes to 907, there is no distortion of the shape of the product and deterioration of quality. The inner diameter of the lower half-matrix

"Iz" is taken to be equal to 1.05...1.3 diameters of the cavity of the upper half-matrix, which allows you to establish an entrance to the transverse cavity outside the zone of power support, which must be provided with a counterpunch during one-sided metal supply.

In addition, the clip can be not only two-stage, but also multi-stage, which allows you to switch from any stage to any other, both in the direction of increase and in the direction of decrease in diameter. - and Profiling of the external contour is carried out due to the local deepening of the protrusion on the transition edge of the upper half-matrix into the workpiece. o Displacement of the rotation zone leads to a change not only in the outer diameter of the product, but also, if necessary,

Gee! 20 internal diameter, which allows you to obtain complex products with a variable external and internal profile at a constant thickness. c By varying the size of the transverse gap and the position of the clip, it is possible to obtain hollow parts with different wall thicknesses, with shaped both inner and outer surfaces.

Fig. 1 schematically presents a section of a stamp for implementing the proposed method, on the left - in the initial state, on the right - the formation of a section of a part with an outer diameter of 0. and a wall thickness of y; in. in Fig. 2 - the same, but with wall thickness b. and with a diameter of 0"; in Fig. 3 and 4 - the formation of an empty part with a complex external and internal profile; in Fig. 5 and 6 - the formation of an empty part with an edge and engraved external grooves.

The method is implemented in a die consisting of a container 1, in which working tools capable of independent 60 longitudinal movement (from individual drives) are placed: deforming - upper punch 2 and lower punch (anti-punch) 3; shape-changing - upper half-matrix 4, lower half-matrix 5 and clip 6.

The starting blank 7 is placed in the cavity of the upper half-matrix 4 on the end of the counter-punch Z and, under the influence of the punch 2, is pressed in the transverse (radial) direction into the transverse gap formed by the upper half-matrix 4 and the lower half-matrix 5, set relative to the upper half-matrix in such a way that the gap, formed by these formative tools, is equal to Her. In the initial stage of the process, the deformed metal, having passed the first turn (zone "a"), flows radially, and after reaching the second angular zone of rotation or spatial bending (zone "6") and colliding with the vertical walls of the clamp, it changes the flow direction to 907" and flows parallel axis of symmetry along the inner side surface of the clip 6, forming a wall

The thickness of this is a cylindrical section with an outer diameter of 3. To obtain a variable thickness of the wall, the size of the gap is changed, for example, it is increased to the thickness of the hole by moving the upper half-matrix 4 relative to the lower half-matrix 5 and the counter-punch З and fixing it in this position. As a result of this, in the process of extrusion, the thickness of the metal that flows in the radial direction first increases, and then the section with this thickness turns and flows parallel to the axis of symmetry, forming the wall of the semi-finished product with 7/0 thickness b, which is different from its original thickness c. A change in the height of the transverse gap can be provided by joint movement of the lower half-matrix 5 and counterpunch Z or by simultaneous displacement of the upper half-matrix 4 and a set of tools (half-matrix 5 and counterpunch 3). At the moment of change in the size of the transverse gap, a transition section of the wall with a thickness of 4 to 5 is formed on top of the flange. By ensuring the necessary ratio of the speed of movement of the punch 2 (and, accordingly, the speed of transverse extrusion /5 of the metal) and the speed of movement (approaching or moving apart) of the forming tools, it is possible to obtain the necessary change in wall thickness and configuration at the specified length (height) of the manufactured part.

It should be noted that the mutual movement of the upper half-matrix 4, the lower half-matrix 5, as well as the clamp 6, is also possible when the pressing force is removed and the punch 2 stops moving. This allows you to significantly reduce the length of the transition section.

To obtain a shaped external profile, along with changing the size of the transverse gap, the height position of the clip 6, which has surfaces of different diameters in height, is changed, and thus the diameter of the outer surface of the part is changed. To do this, the clip b is moved up to the coincidence of the conical sections of the upper half-matrix 4 and the clip b (these forming tools form the corner turning zone "6"), the diameter of the inner side surface of the clip 6 increases. Thus, before the approach of the section of the product with its thickened wall, the section of the clip with its larger diameter of the inner surface is exposed. As a result of this, in the process of extrusion, the metal of increased thickness Ko first flows radially, and after colliding with the "walls of the expanded section of the clamp b, it changes direction by 90", finally turns around and flows along the axis of symmetry, forming a part with a wall thickness of 5 and an outer diameter of O. which differs from its original diameter 03. Thus, the proposed method allows you to obtain empty parts with variable (stepped) external profile and with different wall thickness depending on the height of the product.

With an unchanged position of the clamp 6 and a constant value of the outer diameter, the change of the gap and, accordingly, the thickness of the wall of the part i is carried out by moving only the lower half-matrix 5 at an unchanged position of Ge! counterpunch 3, which will lead to obtaining steps only from the bottom of the flange and to a change in the internal diameter, a complication of the internal profile (Fig. 3). uh-

With an unchanged gap and wall thickness of the part (, a change (increase or decrease) in the outer diameter will be accompanied by a change in the inner diameter, which makes it possible to obtain multi-stage hollow parts with a complex outer and inner profile (Fig. 4).

The combination of various options for changing the size of the transverse gap with options for changing the position of the clip in height allows you to obtain details of complex configurations with a shaped external and internal profile of various standard sizes in one stamp. з с To obtain a shaped external profile, only the upper half-matrix 4 can be moved. At the same time, it is advisable to reduce the wall thickness by locally deepening the protrusion on the transitional edge. of the upper half-matrix 4. In combination with the tension of the wall of the part by the forces applied by the clip 6, this makes it possible to obtain parts of the "glass" type with a rim and several narrow grooves "c" on the outer surface (fig. 5 and 6). Profiling of the internal contour is performed by moving the lower half-matrix 5

Ge" relative to the counterpunch Z and the upper half-matrix 4.

Example.

Sh- Blanks with a diameter of 0-28.1 mm from the ADI alloy after applying lubricant (animal fat) were extruded in a cold state according to the proposed method. First, 5p metal was extruded into the transverse gap with a height of Zmm along a 12 mm stroke of the punch and an empty part with a relatively equal wall thickness was formed

Me, (decreasing the thickness of the wall of the part after turning the metal flow by 90" by 0.3...0.5 mm) with a height of 15 mm and an outer diameter of 0-4 mm. Then the size of the gap was increased to 5.0 mm by moving the matrix up (Fig. 2 ). After the stroke of the punch by 14 mm, the clip was moved up in such a way that a vertical cavity with a diameter of 05-44 mm was formed. With further movement of the punch by 17 mm, a part with a stepped outer surface with a total height of 40 mm and a step height of a smaller diameter of 1 mm was obtained.

Thus, the proposed method allows you to obtain empty parts with different wall thicknesses, with

P shaped both internal and external surface, which significantly expands the technological possibilities of the process.

The proposed method allows you to reduce the volume, and in some cases to eliminate mechanical processing due to ensuring a high-quality and clear transition from step to step, to increase manufacturing productivity, while ensuring high quality and accuracy.

Sources of information: 1. US patent Mo3263468, cl. 72-46, 1979. 2. Copyright certificate of the USSR Mo1017399, B21С3/00, 1981. for

Claims (5)

The formula of the invention 1. The method of extruding hollow parts with a shaped side surface, which consists in radially extruding the workpiece material into the transverse gap between the upper die and the lower movable support, followed by a change in the direction of the metal flow to a straight line along the inner side surface of the die, which is characterized by the fact that the upper forming tool is divided into a half-die and a clip, the lower working tool is divided into a deforming counterpunch and a forming half-die, while the inner diameter of the lower half-die is taken to be equal to 1.05...1.3 of the diameter of the cavity of the upper half-die, the size of the gap during transverse extrusion is changed due to the axial movement of one of 70 forming tools or their combination, the diameter of the outer surface of the part is changed due to the longitudinal movement of the clip, which has surfaces of different diameters in height. 2. The method according to claim 1, which is distinguished by the fact that the change in the direction of the metal flow can be multi-stage, which allows you to switch from any stage to any other, both in the direction of increase and in the direction of decrease in diameter. Q. The method according to claim 1, which differs in that the profiling of the external contour is carried out due to the local deepening of the protrusion on the transition edge of the upper half-matrix into the workpiece. 4. The method according to claim 1, which is distinguished by the fact that the displacement of the rotation zone leads to a change not only in the outer diameter of the product, but also, if necessary, in the inner diameter, which allows obtaining complex products with a variable external and internal profile at a constant thickness. 5. The method according to claim 1, which differs in that by varying the size of the transverse gap and the position of the clamp, it is possible to obtain hollow parts with different wall thicknesses, with a shaped inner and outer surface. « «c) then that (o) in (Se) - and? (o) -i se) (o) (42) 60 b5