KR20140089986A - Deformation method of radial or hoop severe plastic for tube materials and processing apparatus thereof - Google Patents

Abstract

The present invention relates to a rigid plasticity processing method for a metal pipe provided to improve mechanical stiffness such as internal pressure fatigue resistance inside and outside a metal pipe, vibration fatigue resistance, cavitation and scratch resistance, and durability while maintaining the shape of the metal pipe, which is manufactured or is being manufactured within a predetermined range; and a rigid plasticity processing apparatus therefore. The rigid plasticity processing method of the metal pipe comprises: a step of compressing a metal pipe wall facing an outer mold or an inner mold or to load the metal pipe between the outer and inner molds spaced apart from the wall of the metal pipe, wherein either the outer mold facing the outer wall of the loaded metal pipe along the circumference of the outer wall or the inner mold facing the inter wall of the loaded metal pipe along the circumference of the inner wall is divided into a plurality of segments, and a gap between the outer and inner molds increased or decreased by a pressurizing drive unit, thereby compressing the wall of the metal pipe; a step of compressing either the outer mold or the inner mold to the faced wall of the metal pipe; and a step of rotating either the outer mold or the inner mold or to pass the metal pipe through the gap between the outer and inner molds.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of machining a steel pipe,

More particularly, the present invention relates to a method and a device for rigid-working a metal tube, and more particularly, to a method and apparatus for processing a metal tube, , Vibration fatigue resistance, cavitation resistance, scratch resistance, bending stability, and the like.

Generally, metallic pipe materials are mainly used for supporting structures, constructing structures, pipes for dividing fluid passages, and the like.

In the production of the metal tube, the relatively large diameter is produced through a process of casting or bending the plate and re-welding it. In the case of a relatively small-sized metal tube, the tube is drawn or extruded, And the like.

These metal tube materials are generally uneven in physical properties, and are locally or globally unevenly deformed, and have a problem of bowing effect generated in the molding process.

Particularly, it is disadvantageous in that the material of the inside of the metal tube along the circumferential direction, including the welded portion, is not uniform even when the plate material is formed by the tube.

As a method for compensating for the disadvantages of the mechanical rigidity or low durability of the metal pipe, there is proposed a method of increasing the thickness or the size of the metal pipe, or plastic deformation using the plastic property as one of the processing methods of the metal material.

Here, increasing the thickness of the metal tube may not only result in unnecessary weight increase and waste of material, but may also be difficult to apply in addition to increasing the size thereof.

On the other hand, in the method of plastic deformation, when the metallic material undergoes plastic deformation, the phenomenon that the crystal grains gradually become finer as the plastic deformation amount increases from the formation of the small boundary cell structure to the grain boundary angle increases.

Recently, there is a rigid processing method in which a large deformation is applied to a metal material to make the grain micro-fine or nanocrystalline.

When the grain size of the metal material is made ultra-fine or nanocrystalline, the above-mentioned rigid-body machining method exhibits excellent mechanical properties (strength, hardness, abrasion resistance, super plasticity, etc.)

Plastic deformation applied to a metal material such as extrusion, tensile, and shear deformation is important for forming such a crystal grain. In order to apply a large amount of plastic deformation, a repeated process is required. In order to enable the above- It is necessary to design the mold so as to have the same material shape.

The presently developed rigid-plastic machining method which enables the repetitive process as described above includes Equal Channel Angular Pressing (ECAP), High-Pressure Torsion (HPT), Accumulative Roll (ARB) Bonding, and Equal Channel Angular Rolling (ECAR).

These rigid-plastic processing methods are common in that the material shapes are similar before and after the process, and it is possible to control the plastic deformation amount and the mechanical properties of the material by controlling the number of revolutions or the number of steps of the mold, It is possible to apply a large plastic deformation, so that it has an effect on strengthening and homogenization of the material due to ultrafine grains and nano-size of the crystal grains.

The present invention relates to a rigid machining method for a metal tube in a metal material and a machine for its application.

The present invention relates to a method for manufacturing a metal tube or a manufacturing method thereof, in which a shape of a metal tube is maintained with respect to a metal tube in a manufacturing process, and a rigid deformation is uniformly added to the entire metal tube so that the crystal grains of the metal material, Hardness, abrasion resistance, super plasticity and the like of the metal tube and to improve the mechanical properties of the metal tube and to make the overall property uniformity of the metal tube so as to have stability and durability including the shape and the apparatus.

It is another object of the present invention to provide a method and apparatus for rigid metal processing that enables repetition or continuous processing on a metal tube and enables adjustment of the amount of deformation and control of mechanical properties thereof.

According to another aspect of the present invention, there is provided a method of rigidly machining a metal tube, wherein at least one of an outer mold facing the outer wall of the metal tube to be mounted and an inner mold facing the inner wall of the metal tube, And a rigid machining device of a metal tube which is divided into a plurality of segments along the periphery of the pipe and is spaced from or spaced apart from each other by a pressurizing drive part so as to press against or face the wall of the metal pipe facing each other, Mounting the metal tube between the outer mold and the inner mold; Pressing the outer mold or the inner mold against the wall surface of the metal tube facing the inner mold; And rotating the outer mold or the inner mold or passing the metal tube between the outer mold and the inner mold.

Preferably, the pressing drive unit is configured to rotate at least one of the outer mold and the inner mold, and further includes a step of rotating the outer tube in a state where the tube is pressed against the wall surface of the metal tube.

Preferably, the plastic deformation amount applied to the metal tube is controlled by controlling the pressing pressure and the rotational speed of the outer mold or the inner mold with respect to the metal tube.

In addition, a heating element is further provided in the outer mold or the inner mold, and a thermometer is further provided on the surface of the outer metal mold or the inner metal mold and the metal pipe passing through the metal mold, And the like.

The metal tube material may have any one of a circular shape, an elliptical shape, and a polygonal shape, and the press driving unit may include a pressing mechanism that presses the metal tube between the outer mold and the inner mold in front of the outer mold and the inner mold, Wherein the step of pressing the outer metal mold or the inner metal mold against the wall surface of the metal tube facing the outer metal mold or the inner mold comprises the step of pressing the outer metal mold and the inner metal mold, And the metal tube may be continuously passed between the outer mold and the inner mold by the pressure roller and the drawing roller.

Further, it is preferable that a heating element is further provided in the outer mold or the inner mold, a thermometer is further provided on the surface of the outer metal mold or the inner metal mold and the metal pipe passing through the metal mold, It is possible to control the plastic deformation conditions of the metal tube by adjusting the pressing pressure of the metal mold and the temperature during processing of the metal tube.

A plurality of pressure rollers for press-fitting the metal tube between the outer mold and the inner mold in front of the outer mold and the inner mold are provided in the press-in direction, and the metal tube is passed through the pressing rollers And a welding portion for welding a widthwise edge portion of the plate material which is in contact with each other by being formed into the tube between the pressing roller and the outer mold and the inner mold, And may be inserted and installed inside the outer mold in the direction of the pressure roller.

According to another aspect of the present invention, there is provided a plastic working apparatus for a metal tube, wherein at least one of an outer mold facing the outer wall of the metal tube to be mounted and an inner mold facing the inner wall of the metal tube, A pressing drive part which is divided into a plurality of segments along the periphery of the metal tube and is provided so as to be capable of being squeezed or opened against the wall surface of the metal tube and pressing the divided segments against the wall surface of the metal tube facing each other And the like.

The outer metal mold is composed of a single tubular shape close to the outer wall of the metal tube, the inner mold is divided into a plurality of inner segments of the segment, and the outer surface of each inner segment of the segments is connected to the inner wall of the metal tube Wherein the inner surface of each of the segments has an inclined surface whose thickness gradually decreases with respect to the one end direction of the metal tube with reference to the outer surface, and the pressure driving portion has a portion extending from one end to the other end, A press-in shaft having a sharp shape so as to face the press-in shaft; A connector for connecting the press-in shaft and the inner mold, and press-fitting the press-in shaft in the other end direction of the inner mold according to a connection position thereof; And a motor connected to any one of the inner mold, the press-in shaft, and the connector to provide a rotational force.

A guide protrusion or guide groove is formed in the center of the inner surface of each of the segments in the width direction along the longitudinal direction. The outer circumferential surface of the press-fit shaft is provided with a guide groove or guide And the motor is connected to the press-in shaft to provide a rotational force.

Each of the segment inner dies is provided with a latching groove having a depth in the center direction of the metal tube at one end or the other end thereof, and the press-in shaft has a male screw formed at one end or the other end, And the other end or the inner surface of the one end is provided with a latching protrusion which is partially inserted into the latching groove, so that the connection position of the connector with respect to the press- So that the press-in depth of the press-in shaft with respect to the inner mold can be controlled.

Alternatively, the outer mold may be divided into a plurality of segment outer molds, the inner surface of each of the segment outer molds facing the outer wall of the metal tube, and the outer surface of each of the segment outer molds Wherein the inner mold has a bar shape that is close to an inner wall of the metal tube, and the pressure driving portion has a portion extending from one end to the other end of the barrel, A press-fitting tube having a gradually thickening shape; A connector for connecting the press-fit pipe to the outer mold and press-fitting the outer mold in the direction of the other end of the press-fit pipe according to the connection position; And a motor connected to any one of the outer mold, the press-fitting pipe, and the connector to provide a rotational force.

A guide protrusion or a guide groove is formed in the center of the outer surface of the outer mold of each of the segments in the width direction along the longitudinal direction and the guide protrusion or the guide groove is formed in parallel with the outer surface. And the motor may be connected to the press-fitting pipe to provide a rotational force.

Each of the outer segments may be formed with an engagement groove having a depth in the center direction of the metal tube at one end or the other end thereof, and the press-fit pipe may be formed with a male screw at one end or the other end, And the other end or the inner surface of the one end is provided with a latching jaw which is partly inserted into the latching groove so that the connection of the connector with respect to the press- And the press-in depth of the outer mold with respect to the press-in pipe is adjusted according to the position.

The outer metal mold is divided into a plurality of segment outer molds, the inner surface of each of the segment outer molds faces an outer wall of the metal tube, and the outer surface of each of the segment outer molds is connected to the other end Wherein the inner mold is divided into a plurality of segment inner molds, the outer surface of each of the segment inner molds faces the inner wall of the metal tube, and each of the inner molds Wherein the inner surface of the metal tube is formed as an inclined surface whose thickness gradually decreases with respect to the one end direction of the metal tube with respect to the outer surface thereof, and the pressure driving portion has a pointed shape such that a portion extending from one end to the other end faces the inclined surface A press-fitting shaft; A connector for connecting the press-in shaft and the inner mold, and press-fitting the press-in shaft in the other end direction of the inner mold according to a connection position thereof; And a motor connected to any one of the inner mold, the press-in shaft, and the connector to provide a rotational force; A press-fitting tube having a shape gradually increasing from the one end to the other end so as to face the inclined surface; A connector for connecting the press-fit pipe to the outer mold and press-fitting the outer mold in the direction of the other end of the press-fit pipe according to the connection position; And a second pressure driving unit including a motor connected to one of the outer mold, the press-fitting pipe, and the connector to provide a rotational force.

As described above, according to the structure of the method for manufacturing a rigid metal tube according to the present invention and the structure of the apparatus, the crystal grains of the metal tube can be formed within a range in which the shape of the metal tube is maintained within a certain range while the metal tube is repeatedly or continuously supplied Ultrafine and nanoized, the rigid-plastic deformation is evenly distributed throughout the metal tube, thereby improving the mechanical properties of the metal tube such as strength, hardness, abrasion resistance and super plasticity of the metal tube, and uniform physical properties of the metal tube It is possible to obtain a metal tube having stability and durability including the shape thereof.

In addition, the present invention enables repetitive or continuous processes for the metal tube, and also has an effect of controlling the plastic deformation amount and controlling the mechanical properties thereof.

FIG. 1 is a flowchart illustrating a process of rigid-body machining of a metal tube according to an embodiment of the present invention.
FIG. 2 is a flowchart illustrating a rigid machining process of a metal tube according to another modification of the present invention.
FIG. 3 is a schematic view sequentially showing a plastic deformation relationship of the metal tube through the process of FIG.
FIGS. 4A and 4B are graphs showing the plastic deformation distribution of the metal tube from the compression pressure by the inner mold and the plastic deformation distribution of the metal tube due to the rotation, together with the compression of the inner mold.
5A and 5B are graphs showing the amount of plastic deformation and the hardness in the thickness direction of the inner wall surface of the metal tube when the inner metal tube is rotated 180 DEG in a state of pressing the inner mold against the inner wall of the metal tube.
6 is a graph showing a change in hardness according to the amount of plastic deformation applied when a high-pressure torsional process is applied to copper used in the simulation of a metal tube.
Figs. 7A and 7B are cross-sectional views schematically showing the configuration of a rigid-metal machining apparatus for a metal tube according to an embodiment of the present invention and the operating relationship of these configurations.
Figs. 8A and 8B are cross-sectional views showing the arrangement states of the outer mold and the inner mold in Figs. 7A and 7B.
Fig. 9 is a schematic cross-sectional view for explaining a configuration of a rigid-material machining apparatus of a metal tube according to a modified embodiment of the present invention and an operating relationship of these configurations.

The terms and words used in the present specification and claims should not be construed to be limited to ordinary or dictionary meanings, but the inventor should be able to properly define the concept of the term in order to best explain his or her invention Should be construed in accordance with the principles of the present invention.

It should be noted that the embodiments described in this specification and the configurations shown in the drawings are merely preferred embodiments of the present invention and do not represent all the technical ideas of the present invention, It should be understood that various equivalents and modifications may be present.

The inclined surface referred to in the present invention indicates the shape of the inner surface and the outer surface corresponding to the inner or outer surface of the structure, .

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 to 3, the method for roughly machining a metal pipe according to the present invention comprises the steps of: forming an outer mold 10 and a metal pipe P facing each other along the outer wall of the metal pipe P, And an inner metal mold 20 facing the inner wall.

At least one of the outer mold 10 and the inner mold 20 is divided into a plurality of segments along the periphery of the metal pipe P and is configured to be able to open and close each other by the pressure driver.

1 and 2, a process of mounting the metal pipe P between the outer mold 10 and the inner mold 20 and the process of mounting the metal pipe P between the outer mold 10 and the inner mold 20, A process of pressing the wall surface of the metal pipe P through the inner mold 10 or the inner mold 20 and a process of rotating at least one of the outer mold 10 and the inner mold 20 pressing the metal pipe P, And a step of plastically deforming the metal pipe P by allowing the metal pipe P to pass between the outer mold 10 and the inner mold 20 that presses the pipe P.

1, the outer metal mold 10 and the inner metal mold 20 are pressed against the metal pipe P lying therebetween while the cross-sectional shape of the metal pipe P is circular. And at least one of the outer mold 10 and the inner mold 20 is rotated and plastic deformed.

The process shown in Fig. 2 is performed by plastic deformation of various metal pipes P, such as ellipses or polygons, while maintaining their cross-sectional shapes, including those having a circular cross-section, A process of pressing the metal pipe P lying therebetween with the corresponding outer mold 10 and the inner mold 20 and allowing the metal pipe P to pass therethrough.

Referring to FIG. 3, a metal pipe P is mounted between the outer mold 10 and the inner mold 20 (ST100). When the mounting of the metal tube P is completed, the above-described pressure driver pushes the wall surface of the metal tube P in the thickness direction thereof through the outer mold 10 or the inner mold 20 (ST110).

The outer mold 10 is pressed against the inner metal mold 20 when the pressure drive unit presses the metal pipe P using the outer mold 10. In this case, The inner mold 20 presses the outer wall surface of the metal pipe P between the inner mold 20 and the inner mold 20 by pressing the metal pipe P using the inner mold 20, And presses the inner wall surface of the metal pipe P sandwiched therebetween by using the outer mold 10 as a supporting base.

When the press driving unit presses the metal pipe P through both the outer mold 10 and the inner mold 20, the outer mold 10 uses the inner mold 20 as a support base, Is to press the wall surface of the metal pipe (P) between the outer metal mold (10) and the outer metal mold (10) in the thickness direction.

Various constructions can be applied to the pressing relationship with respect to the metal tube P, which will be described in more detail with reference to the embodiments of the metal tube rigging apparatus described below.

The pressure drive unit may press the wall surface of the metal pipe P in the thickness direction thereof through at least one of the outer mold 10 and the inner mold 20 as described above, The metal mold 20 is rotated to cause twisting deformation on the surface of the metal pipe P placed therebetween (ST120).

At this time, the pressing pressures of the outer mold 10 and the inner mold 20 act strongly on the surface layer of the metal tube P and are uniformly formed around the wall surface of the metal tube P by the twist deformation, To-face relationship.

Therefore, the surface of the metal pipe P on which the pressing pressure acts is not only smoothly formed, but also the mechanical strength is higher in the surface layer.

4A shows a state in which the metal pipe P is made of copper and the metal pipe P is inserted into the inner metal mold 20 while the metal pipe P is tightly inserted into the inner pipe 10, FIG. 4B is a graph showing the distribution of the plastic strain with respect to the thickness of the metal pipe P in a state where the inner wall is pressed at a constant pressure. FIG. Plastic strain distribution.

5A and 5B show simulation results of the effective strain in the state in which the inner mold 20 is rotated 180 DEG with respect to the metal pipe P and the hardness thereof in the thickness direction of the metal pipe P Fig.

As can be seen in FIG. 5A, it can be seen that the strain exhibits a high strain at the surface pressed by the inner mold 20, and the resulting hardness is also deformed at a similar rate.

6 shows simulation data on the strain when the inner metal mold 20 is rotated 180 ° with respect to the metal pipe P and measurements of hardness with respect to the surface. FIG. 5B is a graph illustrating the change in the hardness using the strain data obtained in FIG. 5A and FIG. 6.

The hardness is saturated after the specific plastic deformation amount, and even if a large amount of deformation is formed inside the tube, the hardness will not be improved up to the specific hardness value (145Hv) or more, and the outside does not reach the deformation amount where the hardness is saturated The degree of hardness improvement is lower than that of the inside of the pipe but it is higher than the initial value.

As can be seen from the above results, it can be seen that the hardness increases with an increase in the surface strain of the metal pipe (P) pressed by the inner mold (20).

The results of the above-described strain results and hardness are the result of the progress of the pressure condition of the torque, but if the pressing pressure is further enlarged, the overall strain increase and the corresponding mechanical rigidity increase in the thickness direction of the metal pipe (P) Can be predicted.

The strain due to the pressing of the metal pipe P is evenly distributed to the inner wall surface of the metal pipe P by the rotation of the inner mold 20 relative to the metal pipe P, Thereby uniformly forming physical properties around the circumference.

In the above process, the metal pipe P is pressed against the inner wall of the metal pipe P while being pressed against the inner metal mold 20, but the hardness due to the strain, that is, the mechanical rigidity is improved. 20 are pressed against the outer wall surface of the metal pipe P with the outer mold 10 as a support base, similar results can be obtained on the outer wall surface of the metal pipe P.

In order to uniformly distribute the strain according to the torsional stress in the entire thickness direction of the metal tube P, the outer and inner walls of the metal tube P are pressed against the outer and inner molds 10 and 20, In addition, a greater amount of deformation can be expected by rotating the outer mold 10 and the inner mold 20 in opposite directions about the metal tube P as a center.

The remaining process of FIG. 1 is a process for separating the metal pipe P from the rigid machining apparatus of the metal pipe. The rotation of the outer metal mold 10 or the inner mold 20 is stopped (ST130) And separates the metal pipe P in a state in which the pressure applied to the pipe P is released (ST140).

2, the metal pipe P has an elliptical shape having a circular cross-sectional shape, and is difficult to rotate while pressing the outer metal mold 10 and the inner metal mold 20 with the metal pipe P, Or a polygonal shape.

2 and 3, a metal pipe P is inserted between the outer mold 10 and the inner mold 20 (ST200), and the outer mold 10 and the inner mold 20 are used to face each other (ST210) and pushing or pulling the metal pipe P placed between the outer mold 10 and the inner mold 20 from either side thereof ST220) so that plastic deformation against the outer wall and the inner wall of the metal pipe P is achieved.

The plastic deformation of the metal pipe P passing through the outer mold 10 and the inner mold 20 is formed in the longitudinal direction of the metal pipe P. [

The above-described rigid machining process of the metal pipe (P) shows that the shape of the metal pipe (P) that has already been manufactured can be repeatedly performed without causing any deformation, but the metal pipe (P) The above process can be done in the process.

7A and FIG. 7B, a metal pipe P is provided in the front of one side of the outer mold 10 and the inner mold 20, that is, the metal pipe P is connected to the outer mold 10 and the inner mold 20 A plurality of pressure rollers L1 and L2 for press-fitting the metal pipe P in the direction in which the outer mold 10 and the inner mold 20 are inserted between the press rollers L2 and L2, A welding portion W is further provided.

The pressing rollers L1 and L2 form a plate material P0 in the process of passing through the plate material P0 and the welding portion W described above is formed at a position where the widthwise edge portions of the plate material P0 are in contact with each other As shown in Fig.

Accordingly, the plate member P0 is formed into the metal pipe P in the course of passing through the plurality of pressure rollers L1 and L2 and the welded portion W sequentially.

The process of mounting the metal pipe P between the outer mold 10 and the inner mold 20 is performed by the pressure rollers L1 and L2 described above by using the outer mold 10 and the inner mold 20, As shown in FIG.

The wall surface of the metal pipe P is pressed through the outer mold 10 and the inner mold 20 so that the distance between the outer mold 10 and the inner mold 20 is smaller than the thickness of the metal pipe P And pressing the metal tube P in a state of keeping it narrowly.

At this time, any one of the outer mold 10 and the inner mold 20 may be divided into a plurality of segments to allow the metal pipe P to pass through the metal pipe P by a predetermined length, It is also necessary for the purpose of adjusting the pressing pressure against the wall and for fixing or repairing.

When the outer mold 10 is formed as a separate mold, the inner mold 20 may have a single rod shape. When the inner mold 20 is formed as a separate mold, the outer mold 10 may have a single And both the outer mold 10 and the inner mold 20 may be formed in a separable shape.

In addition, the above-described rear portion of the outer mold 10 and the inner mold 20 guides the transfer of the metal pipe P passing therethrough, and at the same time, the metal pipe P (P) from the outer mold 10 and the inner mold 20, And a take-out roller L3 for taking out the sheet P from the take-out roller L3.

Here, when the gap between the outer mold 10 and the inner mold 20 is formed to be equal to or less than the thickness of the metal pipe P, the pressurizing drive unit is provided with the pressurizing rollers L1 and L2 or the pressurizing rollers L1 and L2 And a drawing roller L3.

The configuration for rotating the outer mold 10 and the inner mold 20 in the configuration of the above-described pressurizing drive unit is the same as the configuration for rotating the inner pipe 20 in the process of forming the metal pipe P from the plate material P0, And a rotating unit 30 such as a motor or a hydraulic motor for supplying a rotating force to one end of the inner mold P in the section where the pressing rollers L1 and L2 are installed is connected .

In addition, in the case of the external mold 10, it can be configured to be connected to another rotating means 32 by means of conventional connecting means 34a, 34b such as a gear and a bearing structure.

In other words, such a configuration can continuously perform the rigid processing on the metal pipe P in the process of forming the plate material P0 into the metal pipe P.

Meanwhile, each of the embodiments of the rigid-material machining apparatus for metal pipes for the rigid machining of the above-described metal pipe (P) and the operating relationship of these structures will be described with reference to FIGS. 7A to 9B.

7A and 8B, one or both of the outer mold 10a and the inner mold 20a are arranged so as to face the metal pipe P, (12a or 22a) divided into a plurality of segments along the circumference of the metal pipe (P), i.e., in the circumferential direction.

At this time, it is preferable that the respective segment dies 12a or 22a are formed in the same shape and size, and they are arranged at an equal angle from the center of the metal pipe P along the circumferential direction.

The inner surface of the segment metal mold 12a or 22a facing the metal pipe P, that is, the outer segment metal mold 12a, is formed of a metal pipe P or a metal pipe P ' And in the case of the segment inner mold 22a, the outer surface has a curvature corresponding to a part of the inner wall surface of the metal pipe P. In this case,

The outer mold 10a of the segment molds 12a and 22a described above is not shown in Figs. 7A and 7B but the inner surface of the outer mold 10a is close to the outer wall of the metal tube P, Only the inner mold 20a can be constituted to have a plurality of segment inner dies 22a while being constituted of a single tubular shape fitted with interference fit.

Although the inner mold 20a of the segment molds 12a and 22a described above is not shown in Figs. 7A and 7B, the outer surface of the inner mold 20a is close to the inner wall of the metal tube P, The inner mold 20a is constituted by a single rod which is fitted with interference, and only the outer mold 10a can be constituted by a plurality of outer mold segments 12a.

First, in the former case, the outer surface of each segment inner metal mold 22a forming the inner metal mold 20a faces the inner wall of the metal pipe P, and the inner surface of each segment inner metal mold 22a is an outer surface (S) in which the thickness of the metal pipe (P) gradually increases with respect to the one end direction of the metal pipe (P).

7A and 7B is a process in which the metal pipe P is plastically deformed continuously in a state in which the metal pipe P0 is formed of the metal pipe P, The direction in which the metal pipe P formed in a tubular shape passes through the outer metal mold 10a and the inner metal mold 20a is referred to as the forward or the other end direction, The direction in which the mold 10a and the inner mold 20a are put in the center will be referred to as a backward or one-end direction.

The pressing drive portion includes a press-in shaft 24a whose shape is reduced in thickness so that the portion extending from the other end to the one end is in close contact with the slope S described above. The press-in shaft 24a and the segment- And has connectors 26a and 28a for connecting the inner mold 20a or the press-in shaft 24a and the inner mold 22a to the other end of the press-in shaft 24a, And a rotating unit 30 such as a motor connected to any one of the rotating members 26a and 28a and providing a rotating force is connected.

The inclined surfaces of the segment inner mold 22a and the corresponding press-in shaft 24a are formed to correspond to the length of the metal pipe P in the longitudinal direction of the press- Or may be formed by dividing two or more sections as shown in Fig. 7A or 7B with respect to the longitudinal direction thereof.

In this configuration, the connectors 26a and 28a shown in FIGS. 7A and 7B are provided with a sleeve 26a that can slide forward and backward along the side wall of the press-in shaft 24a. On the inner wall of the sleeve 26a, A guide rail R having a length in the tube forming direction is formed so as to protrude along the inner wall and a guide rail R that is paired with the above described guide rail R is formed on the side wall of the corresponding press- And is configured to rotate along with the press-in shaft 24a at the same time while sliding forward and backward along the longitudinal direction of the press-in shaft 24a.

A guide protrusion G having a length in the outward direction from the center of the press-in shaft 24a is formed to protrude from the other end portion of the sleeve 26a in front of the sleeve 26a, and a corresponding one of the segment inner mold 22a A pair of guide grooves are formed in pairs so as to correspond to the guide protrusions G so that the guide protrusions G can slide in the longitudinal direction of the guide protrusions G,

It is preferable that the guide protrusion G and the guide groove are formed so as to have a normal coupling structure to prevent the inner segment 22a and the sleeve 26a from being separated from each other in the longitudinal direction of the press-in shaft 24a.

The sleeve 26b is provided at its one end with a nut 28b having a female thread formed on the inner wall of the end of the end thereof in a single pipe shape and a male thread is formed on a sidewall of the pressing shaft 24a corresponding to the female thread of the nut 28a The other end portion of the nut 28b and the one end portion of the sleeve 26a corresponding to the nut 28b are in close contact with each other or the nut 28a is rotatable about the press- And may be combined with the concavo-convex structure.

When the nut 28a is moved in the direction of the other end of the press-fitting shaft 24a by screwing with the press-fitting shaft 24a, the sleeve 26a pushed through the nut 28a moves to the inside of the segment inner mold 22a The segment inner mold 22a is moved forward by the inclined surface S abutting the press-in shaft 24a and at the same time the center of the press-in shaft 24a is pressed to press the inner wall of the metal pipe P .

At this time, the configuration of the segment inner dies 22a, the press-in shaft 24a, and the connectors 26a, 28a is made up of one inner die 20a having a degree of engagement with the inner wall of the metal pipe P The above-described pivoting means 30 may be connected to the inner mold 20a in a state where the coupling of the above-described structure is fixed and provide a rotational force, and one end of the pushing shaft 24a or one end of the connector 26a, 28a, 28a, 28b, 28c, 28d, and 28d.

As shown in Fig. 8A or 8B, in relation to the rotational force of the rotating means 30, the segment inner metal mold 22a has a length in the widthwise central portion of the inner surface of each segment inner metal mold 22a A guide protrusion 25a corresponding to the guide groove 23a described above is formed on the inclined surface S of the press-in shaft 24a corresponding to the guide groove 23a, It is possible to stably transfer the rotational force provided from the rotating means 30 to each of the segment inner dies 22a.

The guide grooves 23a and the guide protrusions 25a described above are provided with guide protrusions 25a on the inclined surface S of the in-segment metal mold 22a, It is needless to say that guide grooves 23a may be formed on the inclined surfaces S of the guide grooves 24a.

On the other hand, the outer mold 10a described above is relatively divided into the plurality of segment outer molds 12a, and the inner surface of each segment outer mold 12a corresponds to the outer wall of the metal pipe P And the outer surface of each segment outer metal mold 12a can be formed to have an inclined surface whose thickness gradually decreases with respect to the other end direction of the metal pipe P with reference to the inner surface.

The inner mold 20a corresponding to the inner mold 20a may have a rod shape whose outer surface is close to the inner wall of the metal tube P or a rod shape which is inserted into the metal tube P by interference fit.

In addition, the pressurizing drive unit includes a press-fitting pipe 14a having a shape gradually increasing in thickness from the one end to the other end so as to face the inclined surface, and connects the press-fitting pipe 14a and each segment outer mold 12a, An outer mold connector 16a for press-fitting the outer segment metal mold 12a into the other end direction of the press-fitting pipe 14a in accordance with the connection position, and either one of the outer mold 10a or the press-fitting pipe 14a and the outer mold connector 16a And other rotating means (32) connected to the connecting members (34a, 34b) for providing rotational force.

In order to allow the rotational force of the other turning means 32 to be stably transmitted to each of the segment outer molds 12a, it is preferable to arrange the outer molds 12a in the longitudinal direction And a guide protrusion 15a corresponding to the guide groove 13a is formed on the inner wall of the press-fitting pipe 14a corresponding to the guide groove 13a.

7A and 7B, a heating element H is further provided inside the outer mold 10a and the inner mold 20a, and the outer mold 10a and the inner mold 20a, (T) for measuring the temperature with respect to the surface of the metal pipe (P ') which is operated at a position close to the metal pipe (20a) and then the temperature of the metal pipe (P' It is preferable to be able to control the machining speed and the like.

The outer mold 10a and the inner mold 20a may be divided into a plurality of segments. In this case, the outer mold 10a and the inner mold 20a may be configured in a combination of the above two cases.

Here, the above-described pressure driving unit divides the pressurizing drive unit according to which the outer mold 10a is divided into the plurality of segment outer molds 12a by the first pressure drive unit, and the inner mold 20a is divided into the plurality of segment inner molds 22a ) Can be divided into the second pressure driving unit.

9A and 9B illustrate a configuration in which the metal pipe P already formed is charged between the outer mold 10b and the inner mold 20b to be plastically deformed, and various embodiments can be applied.

The difference between the configuration shown in Figs. 9A and 9B and the configuration shown in Figs. 7A and 7B is that the press-in shaft 24b of the constitution of the inner mold 20b forms a sharp sloped surface in the other end direction, The thickness in the longitudinal direction of the segment inner metal mold 22b corresponds to the inclined surface formed on the press-in shaft 24b, and the inner surface gradually increases in the other end direction, and the inclined surface direction is reversed.

The segment inner mold 22a is opened from the center of the press-in shaft 24b by the forward end of the press-in shaft 24b in the other end direction, and the side wall of the mounted metal pipe P is inserted into the outer mold 20b So as to press against the support base.

9A and 9B show that the metal pipe P 'already manufactured is charged from the front of the outer mold 10b and the inner mold 20b.

The configuration of the outer mold 10b is not greatly different from the configuration shown in Figs. 7A and 7B, and a description thereof will be omitted.

Description of the Related Art [0002]
10, 10a, 10b: outer mold 12a, 12b: outer mold segment
14a, 14b: press-fitting pipes 16a, 16b: outer mold connector
20, 20a, 20b: inner molds 22a, 22b: inner mold segment
24a, 24b: press-in shaft 26a, 26b: inner mold connector
30, 30 ', 32: rotating means 34a, 34b: connecting means

Claims (15)

At least one of an outer mold facing the outer wall of the metal tube to be mounted and an inner mold facing the inner wall of the metal tube is divided into a plurality of segments along the periphery of the metal tube, And a metal-made rigid-material machining device configured to be opened or closed,
(a) mounting the metal tube between the outer mold and the inner mold;
(b) pressing the outer mold or the inner mold against the wall surface of the metal tube; And
(c) rotating the outer mold or the inner mold or passing the metal tube between the outer mold or the inner mold;
Wherein the method comprises the steps of:
The method according to claim 1,
Wherein the pressure driver includes at least one of the outer mold and the inner mold,
And rotating the outer mold or the inner mold in a state of pressing the wall surface of the metal tube.
3. The method of claim 2,
And the pressing pressure and the rotational speed of the outer mold or the inner mold with respect to the metal tube are controlled by the pressure driver.
3. The method of claim 2,
A heating element is further provided in the outer mold or the inner mold and a thermometer is further provided on at least one of the outer mold or the inner mold and the surface of the metal pipe passing through the mold, And the temperature is controlled.
The method according to claim 1,
Wherein the metal tube material has a shape of a circular cross section, an elliptic cross section, or a polygonal cross section,
The press driving unit includes a pressing roller for pressing the metal tube between the outer mold and the inner mold in front of the outer mold and the inner mold and a pressing roller for pressing the metal tube passing through the outer mold and the inner mold, And at least one of the pull-out rollers,
Wherein the feeding of the metal tube by the pressing roller or the drawing roller of the pressing driving part is performed in a state of pressing the wall surface of the metal tube facing the outer mold or the inner mold.
6. The method of claim 5,
Wherein a heating element is further provided in the outer mold or the inner mold and a thermometer is further provided on at least one of the outer mold or the inner mold and the surface of the metal pipe passing through the mold, Or the pressing pressure of the inner mold and the temperature at the time of processing the metal tube are controlled.
7. The method according to any one of claims 1 to 6,
A plurality of pressure rollers for press-fitting the metal tube between the outer mold and the inner mold are provided in front of the outer mold and the inner mold, and a weld is additionally provided between the outer and inner molds and the pressure roller adjacent thereto , The metal pipe material is welded by the welding portion in the width direction edge portions where the plate material is formed into a tube shape in the process of passing through the pressure rollers,
Wherein the step (a), the step (b), and the step (c) are performed while the metal pipe material formed in the course of passing through the pressure roller and the welded part is pressed into the outer mold and the inner mold, Processing method.
At least one of an outer mold facing the outer wall of the metal tube to be mounted and an inner mold facing the inner wall of the metal tube is divided into a plurality of segments along the periphery of the metal tube, Wherein the first and second tapered portions are formed to be widened or tapered.
9. The method of claim 8,
Wherein the outer mold is formed into a single tube shape close to the outer wall of the metal tube,
Wherein the inner mold has an inner mold,
Wherein the inner surface of each of the inner molds of each of the segments has a thickness gradually increasing with respect to the one end direction of the metal pipe with respect to the outer surface of the inner surface of the metal pipe, And an inclined surface which is thickened,
The pressure-
A press-in shaft having a shape gradually increasing in thickness so that a portion from one end to the other end faces the slope; A connector that connects the press-fit shaft and the inner mold and press-inserting the inner mold in the other end direction of the press-in shaft according to a connection position thereof; And a turning means connected to any one of the inner mold, the press-in shaft, and the connector to provide a turning force.
10. The method of claim 9,
Wherein a guide protrusion or a guide groove is formed in the central portion in the width direction of the inner surface of each of the segment inner molds in parallel with the inclined surface formed by the inner surface along the longitudinal direction,
A guide groove or a guide protrusion corresponding to the guide protrusion or the guide groove is formed on the outer surface of the press-
And the pivoting means is connected to the press-in shaft.
10. The method of claim 9,
Wherein the connector comprises:
A guide rail extending in the longitudinal direction is formed along the inner wall and a guide protrusion having a length in the outward direction from the center is formed at the other end so as to be fitted to the side wall of the press-in shaft; And a nut having a tubular shape and having a female screw formed on its inner wall,
Wherein the press-fit shaft is formed with a guide rail paired with the guide rail, and a male screw is formed at a portion corresponding to the female screw,
Wherein one end of the segment inner mold is formed with a guide groove formed in a pair with the guide protrusion,
Wherein the press-in depth of the inner mold with respect to the press-in shaft is adjusted according to the connection position of the nut with respect to the press-in shaft.
9. The method of claim 8,
Wherein the outer mold is divided into a plurality of segment outer molds, the inner surface of each of the segment outer molds faces an outer wall of the metal tube, and the outer surface of each of the outer segments of the segments is arranged with respect to the other end direction of the metal tube And an inclined surface whose thickness gradually decreases,
Wherein the inner mold is of a rod shape close to an inner wall of the metal tube,
The pressure-
A push-in tube that gradually increases in thickness so that a portion from one end to the other end faces the slope; A connector for connecting the press-fit pipe to the outer mold and press-fitting the outer mold in the direction of the other end of the press-fit pipe according to the connection position; And a turning unit connected to any one of the outer mold, the press-fitting pipe, and the connector to provide a turning force.
13. The method of claim 12,
A guide protrusion or guide groove is formed in the center of the outer surface of each of the outer molds in the width direction along the longitudinal direction,
A guide groove or a guide protrusion corresponding to the guide protrusion or the guide groove is formed on the inner surface of the press-
Wherein the turning means is connected to the press-fitting pipe to provide a turning force.
13. The method of claim 12,
Wherein each of the outer molds of each of the segments is formed with an engagement groove having a depth in the center direction of the metal pipe at one end thereof,
The press-fitting pipe has a male thread formed on an outer surface of one end,
The connector has a tubular shape and a female thread which is paired with the male thread of the press-in pipe is formed at one end inside, and a hook is formed on the inner surface of the one end,
Wherein the depth of insertion of the outer mold with respect to the press-fitting pipe is adjusted according to a connection position of the connector with respect to the press-fitting pipe.
9. The method of claim 8,
Wherein the outer mold is divided into a plurality of segment outer molds, the inner surface of each of the segment outer molds faces an outer wall of the metal tube, and the outer surface of each of the outer segments of the segments is arranged with respect to the other end direction of the metal tube And an inclined surface whose thickness gradually decreases,
Wherein the inner mold is divided into a plurality of segment inner molds, the outer surface of each of the segment inner molds facing the inner wall of the metal tube, and the inner surface of each of the inner molds of the segments is arranged with respect to one end direction of the metal tube And an inclined surface whose thickness gradually becomes thick,
The pressure-
A press-fitting pipe which gradually increases from the one end to the other end of the outer mold so as to face the inclined surface; A connector for connecting the press-fit pipe to the outer mold and press-fitting the outer mold in the direction of the other end of the press-fit pipe according to the connection position; And a rotating unit connected to one of the outer mold, the press-fitting pipe, and the connector to provide a rotational force;
A press-in shaft having a shape gradually increasing from the one end to the other end with respect to the inner mold so as to face the inclined surface; A connector that connects the press-fit shaft and the inner mold and press-inserting the inner mold in the other end direction of the press-in shaft according to a connection position thereof; And a second pressing driving unit connected to one of the inner mold, the press-in shaft, and the connector and configured to rotate to provide a rotating force.

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