WO2022082894A1

WO2022082894A1 - Cold drawing die set and cold drawing method for multifunctional rod

Info

Publication number: WO2022082894A1
Application number: PCT/CN2020/128023
Authority: WO
Inventors: 程世友; 姚斌斌; 潘佳欢; 叶少军
Original assignee: 浙江晶日科技股份有限公司
Priority date: 2020-10-19
Filing date: 2020-11-11
Publication date: 2022-04-28
Also published as: CN112337989B; CN113500108A; CN113500108B; CN112337989A

Abstract

A cold drawing die set and cold drawing method for a multifunctional rod. The cold drawing die set comprises a straight-groove drawing die (1) consisting of a mounting cylinder I (11) and at least one straight-groove drawing portion (12) arranged on an inner wall of the mounting cylinder I (11), and a bent-corner drawing mold (2) consisting of a mounting cylinder II (21) and a bent-corner drawing portion (22), which is arranged on an inner wall of the mounting cylinder II (21) and is used for bending a straight groove drawn by the straight-groove drawing portion (12). The bent-corner drawing portion (22) comprises a first bent face portion (221) and a second bent face portion (222), which are connected to the inner wall of the mounting cylinder II (21), and a connecting face portion (223) that connects the first bent face portion (221) and the second bent face portion (222), wherein the first bent face portion (221) and the second bent face portion (222) are bent towards the inner wall of the mounting cylinder II (21). By means of the cold drawing die set and the cold drawing method, a workpiece with a high structural strength, a good deformation-resistant performance and a smaller allowable wall thickness can be cold-drawn; the drawing process saves more materials and costs; and an external apparatus can be easily mounted. By means of two instances of cold drawing, the breakage rate of pipes is low, the forming rate thereof is high, and the manufacturing efficiency thereof is higher.

Description

A kind of multifunctional rod cold drawing die set and cold drawing method

technical field

The invention relates to the field of rod manufacturing, in particular to a multifunctional rod cold drawing die set and a cold drawing method.

Background technique

At present, the design structure of most steel rods is smooth and cylindrical, and it is more troublesome to install some external equipment on the steel rod. Therefore, the method of designing grooves on the steel rod is gradually introduced, and the external equipment is installed in the grooved part. However, the design and structure of the grooves are also different. In order to ensure the portable installation and removal of the external equipment and the steel rod, the shape and position of the grooves designed on the steel rod are also extremely important.

A portable street light pole structure with the application number of 201820302520.1, the patent also has grooves running through the upper and lower ends on the side wall of the street light pole, and the open end of the groove has a taper. A hollow part is arranged in between, and the hollow part runs through the upper and lower ends of the side wall of the lamp post. In this patent, the designed groove solves the problem of portable installation and removal of external equipment and steel poles, and the hollow structure is used to reduce the weight and material of the lamp post. However, although the hollow structure is designed, the side wall of the lamp post is A lot of materials are still used, and the structural strength of the groove is not very good, and it is easy to deform and cause the loosening or even sliding of the external equipment.

For the summary of the above problems, there are two requirements for the steel rod structure. On the one hand, it is to reduce the weight of the steel rod and reduce the waste of the steel rod material, and on the other hand, the strength design of the groove is to solve the connection problem of the external equipment.

In addition, at present, the use of cold-drawn dies to draw rods is a common choice, and most rods produced by cold-drawing are smooth cylindrical steel structures, and the rods are one-time Due to the cold drawing process, the drawing force is large, the drawing control is difficult, the shape and precision of the rod are difficult to be precisely controlled, and quality defects such as tube wall rupture or strain are prone to occur during the cold drawing process.

technical problem

The traditional cold drawing die and its cold drawing method are difficult to draw a multifunctional rod with good structural strength, strong deformation resistance, smaller wall thickness, more material saving, cost saving, and convenient installation of external equipment.

technical solutions

Aiming at the deficiencies of the prior art, the present invention aims to provide a multifunctional rod that can be cold drawn, has good structural strength, strong deformation resistance, allows smaller wall thickness, saves materials, saves cost, and is convenient for installing external equipment. Cold-drawing die set and cold-drawing method, through two cold-drawings, the pipe rupture rate is low, the forming rate is high, and the manufacturing efficiency is higher.

Among them, the multi-functional rod cold drawing die set includes:

A straight-groove drawing die composed of the first installation cylinder and at least one straight-groove drawing part arranged on the inner wall of the installation cylinder 1, and the installation cylinder an angle drawing die formed by bending the straight groove drawn from the straight groove drawing wall;

The straight groove drawing part and the inner wall of the mounting cylinder 1 form a cold drawn hole 1 whose outlet is smaller than the inlet;

The angled drawing portion is arranged corresponding to the straight groove drawing portion, and forms a cold drawing hole 2 with the inner wall of the second mounting cylinder whose outlet is smaller than the inlet, and the inlet of the cold drawing hole 2 is larger than the cold drawing hole 1. exports;

The corner drawing part includes a first bending surface, a second bending surface, and a connecting surface connecting the first bending surface and the second bending surface connected with the inner wall of the installation cylinder, the first bending surface The bending surface and the second bending surface are bent toward the two inner walls of the installation cylinder.

Through the double cold drawing of the straight groove drawing die and the curved drawing die in the die set, the first installation formed by the first bending surface with an opening smaller than the inside of the drawn cold drawn rod is formed. The installation groove formed by the wall, the second installation wall formed by the second bending surface, and the connecting wall formed by the connecting surface, the installation groove relies on the first installation wall and the second bending surface formed by the first bending surface. The friction of the formed second mounting wall is used to fix the outer connecting piece, therefore, no fastener is required, which not only causes less damage to the structure of the rod body, but also is very convenient when installing the outer connecting piece. On the cold drawn rod finally drawn, the first mounting wall/second mounting wall and the connecting wall and the supporting wall formed by the second inner wall of the mounting cylinder form a triple folded structure, so that the structural strength at the mounting groove is better and resistant to The deformation ability is stronger, so through two cold drawing, a multi-functional rod with good structural strength, deformation resistance, smaller wall thickness, more material saving and cost saving can be cold drawn. Through cold drawing twice, the pipe breakage rate is low, the forming rate is high, and the manufacturing efficiency is higher, and the drawing die has a simple structure and low cost.

Preferably, the first bending surface portion and the second bending surface portion are integrally connected with the mounting cylinder. Therefore, there is no connection gap between the first bending surface/second bending surface and the second inner wall of the installation cylinder, which is equivalent to that the first bending surface/second bending surface and the second inner wall of the installation cylinder are smoothly connected, and the drawing The process is smoother and there will be no breakage.

Preferably, the included angle α1 between the first bending surface and the second inner wall of the installation cylinder is 30°~60°, and the included angle α2 between the second bending surface and the second inner wall of the installation cylinder is 30°~60° 60°. A reasonable angle not only ensures the structural strength of the installation groove of the cold drawn rod, but also prevents the pipe wall from cracking during the drawing process.

Preferably, the outlet of the second cold-drawn hole is smaller than the outlet of the first cold-drawn hole. It can be drawn into cold-drawn rods with smaller cross-sections, saving more material.

Preferably, an oil injection hole is provided on the inner wall of the first installation cylinder.

Preferably, the first bending surface portion and the second bending surface portion are connected to the second inner wall of the installation cylinder through a rounded portion. In the drawing process, the rupture rate of the pipe can be further reduced, and the drawing forming rate can be improved.

Preferably, the height h2 of the angled drawing portion is not greater than the height h1 of the straight groove drawing portion. During the cold drawing process of the corner drawing die, the first bending surface/second bending surface actually plays the role of expanding or expanding the interior of the straight groove. Therefore, during the drawing process, the steel pipe has both edges. The plastic deformation in the drawing direction also has plastic deformation perpendicular to the drawing direction, and through this setting, the height of the straight groove drawn by the straight groove drawing die is greater than the height h2 of the angled drawing part, therefore, When drawing with a corner drawing die, the pipe at the straight groove can provide more plastic deformation material to the first bending surface and the second bending surface to prevent the pipe from being too thin during the drawing process. Fracture, further reduce the fracture rate and improve the cold drawing rate.

Preferably, the inner wall of the second mounting cylinder includes a connecting wall portion connected with the corner drawing portion and a bending wall portion connected with the connecting wall portion and bent toward the corner drawing portion. This arrangement further strengthens the supporting wall formed by the second inner wall of the mounting cylinder, the structural strength at the mounting groove is better, the deformation resistance is better, the pipe material can be thinner, and the material and cost can be further saved.

Preferably, the angled drawing parts are symmetrically distributed on the second inner wall of the installation cylinder. More installation grooves can be cold drawn, more external connection parts can be installed, and the force is symmetrical, the structural damage to the cold drawn rod is smaller, the performance of the cold drawn rod is better, and the structural strength is better.

Preferably, the angled drawing parts are distributed on the inner wall of the second inner wall of the installation cylinder in a circumferential distribution. The force of all installation grooves on the cold-drawn rod is concentrated at the center of the cold-drawn rod, that is, the cold-drawn rod bears the bending force brought by each external connection with the maximum width, and the resistance of the cold-drawn rod is The deformation ability is stronger.

Preferably, the inner wall of the first installation cylinder includes a rounded wall portion connected to the straight groove drawing portion. The existence of the rounded wall part, on the one hand, in the process of cold drawing using the straight groove drawing die to prevent the pull due to excessive plastic deformation during the cold drawing process, on the other hand, through the straight groove drawing The cold drawn rod drawn from the mold has a large R part. The existence of this R part makes the plastic deformation of the material smoother in the next cold drawing, further reduces the rupture rate and improves the cold drawing forming rate.

Preferably, it also includes a fine drawing die with three cold drawn holes, the cross-sectional shape of the third cold drawn hole is the same as that of the second cold drawn hole, and the size is smaller than that of the second cold drawn hole. Through fine drawing, it can be further drawn into cold drawn rods with smaller cross-section, which saves more material.

Preferably, the first installation cylinder and the second installation cylinder both include a sleeved outer wall surface and a stop end surface connected to the sleeved outer wall surface.

Preferably, the cold drawn hole 1 includes a drawn hole section 1 gradually narrowing from the inlet to the outlet, and a shape-retaining hole section 1 connected to the end of the drawn hole section 1, and the shape-retaining hole section 1 has a cross section that is the same as the The cross-sections at the tail of the drawing hole segment one are coincident.

Preferably, the cold drawn hole 2 includes a drawn hole section 2 that gradually narrows from the inlet to the outlet, and a shape-retaining hole section 2 connected to the tail of the drawn hole section 2. The shape-retaining hole section 2 has a cross section that is the same as the The cross-sections at the tail of the second drawing hole segment coincide with each other.

A multifunctional rod cold drawing method for cold drawing by using the above cold drawing die set, comprising the following steps:

Step 1: Install the straight groove drawing die, extend the pipe into the cold drawing hole 1 of the straight groove drawing die, and draw the pipe to obtain the rod body 1 with a straight groove on the inner wall;

Step 2: Install the corner drawing die, align the straight groove of the rod body 1 with the corner drawing part and insert the rod body 1 into the cold drawing hole 2 of the corner drawing die, and then pull the rod body 1 , so that the side wall of the straight groove is bent in the direction of the pipe wall of the rod body 1, and the rod body 2 is obtained by drawing.

By this method, a cold drawn rod with a straight groove is drawn first, and then the groove wall of the straight groove is bent and drawn, so that the installation groove converted from the straight groove is composed of the first installation wall, the second installation wall, the The connection wall connecting the first installation wall and the second installation wall is formed, the size of the notch of the installation groove is smaller than the internal size, and the installation groove is formed by the first installation wall/second installation wall, the connection wall and and The supporting walls connected by the first installation wall/the second installation wall form a triple-folded structure. Therefore, by cold drawing twice, it can be cold drawn with good structural strength, strong deformation resistance, smaller wall thickness, and more material saving. , Cost-saving, and multi-functional rod with convenient installation of external equipment, through two cold-drawings, the pipe rupture rate is low, the forming rate is high, and the manufacturing efficiency is higher.

beneficial effect

1: The present invention provides a die set with a straight-groove drawing die and a curved-angle drawing die. Through two cold-drawings of the straight-groove drawing die and the curved-angle drawing die, the cold-drawn structure has good structural strength and is resistant to The multi-function rod with strong deformation ability, smaller wall thickness, more material and cost saving, and convenient installation of external equipment, through two cold drawing, the pipe rupture rate is low, the forming rate is high, and the manufacturing efficiency is higher;

2: the present invention connects the first bending face part, the second bending face part and the installation cylinder two into one, and reaches the purpose of smooth connection between the first bending face part/the second bending face part and the two inner walls of the installation cylinder, and the drawing process It is smoother in the middle and will not break;

3: In the present invention, the included angle α1 between the first bending surface and the second inner wall of the installation cylinder and the included angle α2 between the second bending surface and the second inner wall of the installation cylinder are limited to 30°~60°, which not only ensures the The structural strength of the installation groove of the cold-drawn rod also prevents the pipe wall from cracking during the drawing process;

4: In the present invention, the outlet size of the cold-drawn hole 2 is set to the outlet size of the cold-drawn hole 1, which can be drawn into a cold-drawn rod with a smaller cross-section, which saves more materials;

5: In the present invention, the first bending surface/second bending surface is connected to the second inner wall of the installation cylinder through the rounded part, so that during the drawing process, the rupture rate of the pipe can be further reduced and the drawing forming rate can be improved. ;

6: In the present invention, the height h2 of the angled drawing portion is not greater than the height h1 of the straight groove drawing portion. So that when drawing with a corner drawing die, the pipe at the straight groove can provide more plastic deformation material to the first bending surface and the second bending surface, preventing the pipe from being too thin during the drawing process. Crack occurs, further reduce the rupture rate and improve the cold drawing rate;

7: In the present invention, the inner wall of the second installation cylinder includes a connecting wall portion connected with the corner drawing portion and a bending wall portion connected with the connecting wall portion and bent toward the corner drawing portion. , so that the supporting wall formed by the second inner wall of the installation cylinder is further strengthened, the structural strength at the installation groove is better, the deformation resistance is better, and the pipe material can be thinner, which can further save materials and costs;

8: In the present invention, the inner wall of the installation cylinder 1 includes a rounded wall portion connected to the straight groove drawing portion. The existence of the rounded wall portion, on the one hand, is used in the cold drawing process of the straight groove drawing die for cold drawing. In the process of cold drawing, it can prevent the pull due to excessive plastic deformation during the cold drawing process. On the other hand, the cold drawn rod drawn through the straight groove drawing die has a large R part. The existence of this R part makes the next time The plastic deformation of the material is smoother during cold drawing, which further reduces the rupture rate and improves the cold drawing forming rate;

9: In the present invention, the die set also provides a fine-drawing die, the cross-sectional shape of the cold-drawn hole 3 is the same as that of the cold-drawn hole 2, and the size is smaller than the size of the cold-drawn hole 2, so that through fine-drawing, it can be further Drawn into cold-drawn rods with smaller cross-sections, saving more material;

10: In the present invention, the cold-drawn hole 1 is designed to include a drawing hole section 1 for drawing and a shape-retaining hole section 1 for maintaining the cross-sectional shape of the rod, and the cold-drawn hole 2 is designed to include a drawing hole section 1 for drawing. The second drawing hole section and the second shape maintaining hole section for maintaining the cross-sectional shape of the rod greatly reduce the rupture rate of the pipe during the drawing process.

Description of drawings

Fig. 1 is the component schematic diagram of cold drawing die set;

Fig. 2 is a schematic cross-sectional view of a straight groove drawing die;

3 is a schematic cross-sectional view of a corner drawing die;

Fig. 4 is the enlarged view of A place in Fig. 3;

5 is a cross-sectional view of a light pole drawn through a cold-drawn hole;

Figure 6 is a cross-sectional view of a light pole drawn through two cold-drawn holes;

Fig. 7 is the cross-sectional schematic diagram of fine drawing die;

Fig. 8 is the sectional schematic diagram of B-B in Fig. 2;

Fig. 9 is the sectional schematic diagram of C-C in Fig. 3;

FIG. 10 is a schematic diagram of the installation of the first installation cylinder and the second installation cylinder and the external support.

BEST MODE FOR CARRYING OUT THE INVENTION

As shown in Figures 1-6, a multi-functional rod cold drawing die set includes a straight groove drawing die 1 and a curved angle drawing die 2, wherein the straight groove drawing die 1 consists of a mounting cylinder 11, which is arranged at the The installation cylinder-11 is composed of a straight-slot drawing part 12 on the inner wall of the installation cylinder, at least one straight-groove drawing part 12, and the straight-groove-drawing part 12 and the inner wall of the installation cylinder-11 form a cold-drawn hole-13. The outlet of the cold drawing hole 13 is smaller than the inlet, and the outlet is 80%~99% of the size of the inlet. The corner drawing part 22 is composed of the corner drawing part 22, which corresponds to the straight groove drawing part 12, and is used for bending the straight groove drawn by the straight groove drawing wall 12, and the number of the straight groove is the same as that of the straight groove. The number of the drawing parts 12 is the same, the straight groove drawing part 12 and the inner wall of the installation cylinder two 21 form a cold drawing hole two 23, the outlet of the cold drawing hole two 23 is smaller than the inlet, and the outlet is 80% to 99% of the size of the inlet. , and the inlet of the second cold-drawn hole 23 is larger than the outlet of the first cold-drawn hole 13, so that the cold-drawn parts drawn through the first cold-drawn hole 13 can be loaded into the inlet of the second cold-drawn hole 23; The corner drawing portion 22 includes a first bending surface portion 221 , a second bending surface portion 222 connected to the inner wall of the mounting cylinder 21 , and a connecting surface portion 223 connecting the first bending surface portion 221 and the second bending surface portion 222 , the first bending surface portion 221 and the second bending surface portion 222 are bent toward the inner wall of the second installation cylinder 21 .

When drawing, first fix the straight groove drawing die 1, use the straight groove drawing die 1 to cold-draw the steel pipe, and the drawn cold-drawn rod has a straight groove 01, and then fix the corner drawing die 2 , using the angle drawing die 2 to cold draw again, so that the first installation wall 021 and the second bending surface 222 formed by the first bending surface 221 with the opening smaller than the inside are formed on the cold drawn rod. The mounting groove 02 formed by the second mounting wall 022 and the connecting wall 023 formed by the connecting surface 223, the mounting groove 02 relies on the first mounting wall 021 and the second bending surface 222 formed by the first bending surface 221. The friction of the formed second mounting wall 022 is used to fix the outer connecting piece, therefore, no fastener is required, which not only causes less damage to the structure of the rod body, but also is very convenient when installing the outer connecting piece. On the cold drawn rod finally drawn, the first mounting wall 021/second mounting wall 022, the connecting wall 023 and the supporting wall 024 formed by the inner wall of the mounting cylinder 21 form a triple folded structure, so that the The structural strength is better and the deformation resistance is stronger. Therefore, by cold drawing twice, a multifunctional rod with good structural strength, deformation resistance, smaller wall thickness, more material saving and cost saving can be cold drawn. Through cold drawing twice, the pipe breakage rate is low, the forming rate is high, and the manufacturing efficiency is higher, and the drawing die has a simple structure and low cost.

Embodiments of the present invention

The content of the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the embodiments of the present invention are only used to illustrate the present invention and not to limit the present invention. Without departing from the technical idea of the present invention, various substitutions and changes are made according to ordinary technical knowledge and customary means in the field, All should be included in the scope of the present invention.

Example 1:

In this embodiment, the first bending surface portion 221 and the second bending surface portion 222 are integrally connected with the second mounting cylinder 21 . Therefore, there is no connection gap between the first bending surface 221/second bending surface 222 and the inner wall of the second installation cylinder 21, which is equivalent to the first bending surface 221/second bending surface 222 and the inner wall of the second installation cylinder 21 It is a smooth connection, which is smoother during the drawing process and will not break.

In this embodiment, the included angle α1 between the first bending surface portion 221 and the inner wall of the second installation cylinder 21 is 30° to 60°, and the included angle between the second bending surface portion 222 and the inner wall of the second installation cylinder 21 is 30° to 60°. α2 is 30°~60°. A reasonable angle not only ensures the structural strength of the installation groove 02 of the cold drawn rod, but also prevents the pipe wall from breaking during the drawing process.

In order to be able to draw a cold drawn rod with a smaller cross-section and save more material, in this embodiment, the outlet of the second cold drawn hole 23 is smaller than the outlet of the first cold drawn hole 13 .

In this embodiment, an oil injection hole is provided on the inner wall of the installation cylinder-11. By injecting oil into the oil injection hole, the friction between the pipe material and the cold-drawn hole-13 during the cold drawing process can be reduced, and a large amount of oil can be prevented during the cold drawing process. The heat affects the quality of cold drawing. Similarly, the inner wall of the installation cylinder 21 is provided with an oil injection hole, which is not shown in the figure.

In this embodiment, the first bending surface portion 221 and the second bending surface portion 222 are connected to the inner wall of the second mounting cylinder 21 through a rounded portion 224 . When cold drawing is performed by using the corner drawing die 2, in order to further reduce the fracture rate of the pipe material, the drawing rate is increased.

In fact, during the cold drawing process of the corner drawing die 2, the first bending surface 221/the second bending surface 222 plays the role of expanding or expanding the interior of the straight groove 01. Therefore, during the drawing process , the steel pipe has both plastic deformation along the drawing direction and plastic deformation perpendicular to the drawing direction. Therefore, in this embodiment, the height h2 of the angled drawing portion 22 is not greater than the height h2 of the straight groove drawing portion 12 height h1. With this arrangement, the height of the straight groove 01 drawn by the straight groove drawing die 1 is greater than the height h2 of the corner drawing portion 22 . The pipe at the first bending surface 221 and the second bending surface 222 can provide more plastic deformation material to prevent the pipe from being too thin and rupture during the drawing process, further reducing the rupture rate and improving the cold drawing. forming rate.

In this embodiment, the second installation cylinder 21 is further designed, that is, the inner wall of the second installation cylinder 21 includes a connecting wall portion 211 connected to the corner drawing portion 22 and a connecting wall portion 211 The bent wall portion 212 is connected and bent toward the corner drawing portion 22 . This arrangement further strengthens the supporting wall 024 formed by the inner wall of the second installation cylinder 21, the structural strength at the installation groove 02 is better, the deformation resistance is better, and the pipe material can be thinner, which can further save material and cost.

In this embodiment, the installation barrel 11 is further designed, that is, the inner wall of the installation barrel 11 includes a rounded wall portion 111 connected to the straight groove drawing portion 12 . The existence of the rounded wall portion 111, on the one hand, during the cold drawing process using the straight groove drawing die 1 for cold drawing, prevents the pulling due to excessive plastic deformation during the cold drawing process, on the other hand, through the straight groove. The cold drawn rod drawn by the drawing die 1 has a large R part 011. The existence of the R part 011 makes the plastic deformation of the material more smooth in the next cold drawing, further reduces the rupture rate and improves the cold drawing forming rate. .

Generally speaking, the setting of the number and position of the corner drawing parts 22 can have a relatively large influence on the structural strength of the cold drawn rod. In this embodiment, the corner drawing parts 22 are symmetrically distributed in the On the inner wall of the second installation cylinder 21, correspondingly, the straight groove drawing parts 12 are also symmetrically distributed on the inner wall of the installation cylinder 1 11, so that more installation grooves 02 can be cold drawn and more external connection parts can be installed. , and the force is symmetrical, the structural damage to the cold drawn rod is smaller, the performance of the cold drawn rod is better, and the structural strength is better. Further, the angled drawing parts 22 are distributed on the inner wall of the second installation cylinder 21 in a circumferential manner, so that the force of all the installation grooves 02 on the cold-drawn rod is concentrated at the center of the cold-drawn rod, which is equivalent to the cold-drawn rod with The maximum width is used to withstand the bending force brought by the outer connecting part, and the cold-drawn rod has stronger deformation resistance.

For the cold drawn hole 13, as shown in FIG. 8 , the cold drawn hole 13 includes a drawn hole section 131 gradually narrowing from the inlet to the outlet and a shape-retaining hole connected to the tail of the drawn hole section 1 131 Section one 132, the section of the shape maintaining hole section one 132 coincides with the section at the tail of the drawing hole section one 131, under the action of the drawing hole section one 131, the pipe can get a straight groove 01, the shape of The retaining hole section 1 132 ensures that the straight groove 01 will not be deformed through the shape retaining hole section 1 132, thereby ensuring that the shape of the rod that finally emerges from the shape retaining hole section 1 132 is the same as that drawn from the drawing hole section 1 131. The shape of the rod is the same. The reason for this design is: in fact, when drawing heavy and long pipes, one end of the pipe is generally squeezed into the cold drawn hole 13, and the end is extended from the other end of the cold drawn hole 13, and then The clamp is used to clamp the pipe and draw it. The clamp generally flattens the pipe. The purpose is to ensure that the pipe is clamped with a thicker thickness, so as to ensure that the pipe will not be broken during the drawing process. It is precisely because the pipe is flattened, It will cause the size of the flattened to be larger than the size of the cold drawn hole 13. If only the drawn hole section 131 is designed, a large bending angle will be formed between the pipe and the drawn hole section 131, and the pipe will be easier. In the present application, in response to this phenomenon, the shape-retaining hole section 1 132 is designed, after the pipe is flattened, a smaller bending angle can be formed between the pipe and the shape-retaining hole section 1 132, which greatly reduces the rupture rate.

Similarly, for the second cold drawn hole 23 , as shown in FIG. 9 , the second cold drawn hole 23 includes a second drawn hole section 231 that is gradually reduced from the inlet to the outlet, and a second drawn hole section 231 connected to the tail of the second drawn hole section 231 The second shape-retaining hole segment 232 has a cross section that coincides with the cross-section at the tail of the second drawing hole segment 231 .

As to how the installation cylinder 11 and the installation cylinder 2 21 can be installed, connecting holes can be opened on the cylinder walls of the installation cylinder 1 11 and the installation cylinder 2 21 and fixed on the external frame by fasteners. 11 and the second installation cylinder 21 are designed as follows: as shown in Figure 10, the installation cylinder one 11 includes a sleeved outer wall surface 0-01 and a stop end surface 0-02 connected to the sleeved outer wall surface 0-01, Similarly, the second installation cylinder 21 also includes a sleeved outer wall surface 0-01 and a stop end surface 0-02 connected to the sleeved outer wall surface 0-01. In this case, when designing the outer frame 0, only A horizontal sleeve hole needs to be designed accordingly. The sleeve hole includes a large diameter section 001 and a small diameter section 002 connected with the large diameter section 001. When installing the installation cylinder 1 11 or the installation cylinder 2 21, only the installation The first tube 11 or the second installation tube 21 can be installed into the large diameter section 001. During cold drawing, the installation tube 11 or the second installation tube 21 is driven by the inner pipe to achieve abutment with the end face of the small diameter section 002. At the same time, for The dismantling of the installation cylinder 11 or the installation cylinder 2 21 is also very convenient. Therefore, under the premise of the structure of the installation cylinder 1 11 and the installation cylinder 2 21, it is beneficial to design a simple structure and easy to disassemble and assemble the installation cylinder 1. 11 or install the external rack of the second cylinder 21, which reduces the design difficulty.

Example 2:

Different from Embodiment 1, the cold-drawing die set further includes a fine-drawing die 3 having a third cold-drawing hole 31. As shown in FIG. The shape is the same, and the size is smaller than the size of the cold-drawn hole II 23, preferably reduced in equal proportions. Through fine drawing, it can be further drawn into cold drawn rods with smaller cross-section, which saves more material.

Example 3:

A multifunctional rod cold drawing method using the above-mentioned cold drawing die set for cold drawing, applicable to the cold drawing die set in any one of Embodiments 1-2, includes the following steps:

Step 1: Install the straight groove drawing die 1, insert the pipe material into the cold drawing hole 1 13 of the straight groove drawing die 1, and draw the pipe material to obtain the rod body 1 with a straight groove on the inner wall;

Step 2: Install the corner drawing die 2, align the straight groove of the rod body 1 with the corner drawing part 22 and extend the rod body 1 into the cold drawing hole 23 of the corner drawing die 2, and then align the rod body First, drawing is performed, so that the side wall of the straight groove is bent in the direction of the pipe wall of the rod body 1, and the rod body 2 is obtained by drawing. Through this method, the cold drawn rod with the straight groove 01 is drawn first, and then the groove wall of the straight groove 01 is bent and drawn, so that the installation groove 02 converted from the straight groove 01 is formed by the first installation wall 021, The second installation wall 022 and the connecting wall 023 connecting the first installation wall 021 and the second installation wall 022 are formed. The slot size of the installation groove 02 is smaller than the internal size, and the installation groove 02 is formed by the first installation wall The wall 021/second installation wall 022, the connecting wall 023, and the supporting wall 024 connected with the first installation wall 021/second installation wall 022 form a triple-folded structure, therefore, the structure can be cold-drawn by two cold-drawings Multifunctional rod with good strength, strong deformation resistance, smaller wall thickness, more material saving, cost saving, and convenient installation of external equipment. After two cold drawing, the pipe rupture rate is low, the forming rate is high, and the manufacturing efficiency is higher. .

Claims

A multifunctional rod cold drawing die set, characterized in that it comprises:

A straight groove drawing die (1) consisting of an installation cylinder one (11), at least one straight groove drawing part (12) arranged on the inner wall of the installation cylinder one (11), and a straight groove drawing die (1) composed of an installation cylinder two (12). 21) Formed by a angled drawing portion (22) arranged on the inner wall of the second installation cylinder (21) and used for bending the straight groove drawn from the straight groove drawing wall (12). Angle drawing die (2);

The straight groove drawing part (12) and the inner wall of the mounting cylinder one (11) form a cold drawing hole one (13) whose outlet is smaller than the inlet;

The angled drawing portion (22) is arranged corresponding to the straight groove drawing portion (12), and forms a cold drawing hole two (23) with an outlet smaller than the inlet with the inner wall of the mounting cylinder two (21), and is cold drawn. The inlet of the second drawing hole (23) is larger than the outlet of the cold drawing hole one (13);

The corner drawing portion (22) includes a first bending surface portion (221), a second bending surface portion (222) connected to the inner wall of the second mounting cylinder (21), and a first bending surface portion (221) connected to the first bending surface portion (221). ) and the connecting surface (223) of the second bending surface (222), the first bending surface (221) and the second bending surface (222) are bent toward the inner wall of the second installation cylinder (21).
The multifunctional rod cold drawing die set according to claim 1, characterized in that the first bending surface (221) and the second bending surface (222) are connected to the second mounting cylinder (21). as one.
A multi-functional rod cold drawing die set according to claim 1, characterized in that the first installation cylinder (11) and the second installation cylinder (21) both comprise a sleeved outer wall surface (0-01) and a Describe the stop end face (0-02) connected to the outer wall surface (0-01) of the sleeve.
The multifunctional rod cold drawing die set according to claim 1, characterized in that the height h2 of the angled drawing portion (22) is not greater than the height h1 of the straight groove drawing portion (12).
The multifunctional rod cold drawing die set according to claim 1, characterized in that the inner wall of the second mounting cylinder (21) includes a connecting wall portion (211) connected to the corner drawing portion (22). ) and a bending wall portion (212) connected to the connecting wall portion (211) and bent toward the corner drawing portion (22).
The multifunctional rod cold drawing die set according to claim 1, wherein the inner wall of the first installation cylinder (11) includes a rounded wall portion (12) connected to the straight groove drawing portion (12). 111).
A multifunctional rod cold drawing die set according to claim 1, wherein the cold drawing hole one (13) comprises a drawing hole segment one (131) that is gradually reduced from the inlet to the outlet, and the first cold drawing hole (131) and the A shape-retaining hole segment one (132) connected to the tail of the drawing hole segment one (131), the cross-section of the shape-retaining hole segment one (132) coincides with the cross-section at the tail of the drawing hole segment one (131) .
A multifunctional rod cold drawing die set according to claim 1, characterized in that the cold drawing hole two (23) comprises a drawing hole segment two (231) that gradually narrows from the inlet to the outlet, and the second cold drawing hole (231) and the The second shape-retaining hole section (232) connected to the tail of the second drawing hole section (231), the cross-section of the second shape-retaining hole section (232) coincides with the section at the tail of the second drawing hole section (231) .
A multifunctional rod cold drawing die set according to claim 1, characterized in that it further comprises a fine drawing die (3) having three cold drawing holes (31); the cross section of the three cold drawing holes (31) The shape is the same as the cross-sectional shape of the cold-drawn hole two (23), and the size is smaller than that of the cold-drawn hole two (23).
A multifunctional rod cold drawing method for cold drawing using the cold drawing die set described in any one of claims 1 to 9, characterized in that, comprising:

Step 1: Install the straight groove drawing die (1), insert the pipe into the cold drawing hole one (13) of the straight groove drawing die (1), and draw the pipe to obtain a rod body with a straight groove on the inner wall one;

Step 2: Install the corner drawing die (2), align the straight groove of the rod body 1 with the corner drawing part (22), and insert the rod body 1 into the cold drawing hole 2 of the corner drawing die (2). In (23), the rod body 1 is then drawn, so that the side wall of the straight groove is bent in the direction of the pipe wall of the rod body 1, and the rod body 2 is obtained by drawing.