阅读说明：本技术 一种微细管材的拉拔模具及拉拔方法 (Drawing die and drawing method for micro-fine pipe ) 是由 李恒 韩廷状 张铎 赵梦月 王峥 杨许冬 于 2021-08-09 设计创作，主要内容包括：本发明提供的一种微细管材的拉拔模具及拉拔方法,其中装置包括：拉拔模具主体,所述拉拔模具主体的一端设置有管材入料口,与所述入料口对称设置有管材出料口；连通所述入料口、所述出料口的拉拔通道,所述拉拔通道上设置有靠近所述入料口的锥面区；所述锥面区上设置有环形油槽或N个注油孔,N大于或等于1,通过对所述环形油槽或所述注油孔注油,对管材进行挤压和润滑处理。本发明提供的拉拔装置及拉拔方法可以提高管材的单道次变形量,减少拉拔道次,提高拉拔效率。(The invention provides a drawing die and a drawing method of a micro-fine pipe, wherein the device comprises: the drawing die comprises a drawing die body, wherein a pipe feeding port is formed in one end of the drawing die body, and a pipe discharging port is symmetrically formed in the drawing die body and the pipe feeding port; the drawing channel is communicated with the feeding port and the discharging port, and a conical surface area close to the feeding port is arranged on the drawing channel; the conical surface area is provided with an annular oil groove or N oil injection holes, N is larger than or equal to 1, and the pipe is extruded and lubricated by injecting oil into the annular oil groove or the oil injection holes. The drawing device and the drawing method provided by the invention can improve the single-pass deformation of the pipe, reduce the drawing passes and improve the drawing efficiency.)

1. A drawing die for a micro-fine pipe is characterized by comprising:

a drawing die main body, wherein one end of the drawing die main body is provided with a pipe material inlet,

a pipe material outlet is symmetrically arranged with the material inlet;

a drawing channel communicating the feeding port and the discharging port,

a conical surface area close to the feeding opening is arranged on the drawing channel;

the conical surface area is provided with an annular oil groove or N oil injection holes, N is larger than or equal to 1, and the pipe is extruded and lubricated by injecting oil into the annular oil groove or the N oil injection holes.

2. The drawing die for the fine tube according to claim 1, wherein a bearing is provided on the drawing passage adjacent to the tapered surface region; the annular oil groove or the N oil holes in the conical surface area are close to the bearing belt.

3. The die for drawing fine pipes according to claim 2, wherein the number and position of the N oil holes are adjustable depending on the size of the pipe to be drawn.

4. The drawing die for the fine pipe material according to claim 2, wherein the annular oil groove is provided with an oil inlet and an oil outlet;

the oil inlet hole with the oil outlet hole symmetry sets up.

5. The drawing die for the fine tube material according to claim 4, wherein the oil inlet is communicated with an oil press through a guide pipe, and an overflow valve is fixedly connected to the guide pipe connected to the oil outlet.

6. The drawing die for the fine pipe according to claim 3, wherein the N oil injection holes are distributed on the same plane of the conical surface area; or at least one oil filling hole and the rest oil filling holes in the N oil filling holes are distributed on different planes of the conical surface area.

7. A drawing method of a fine pipe characterized by applying the drawing die of any one of claims 1 to 6, the method comprising:

connecting an oil press with an oil filling hole in the conical surface area of the drawing die by using a guide pipe;

placing one end of a pipe to be drawn into a feeding opening of the drawing die;

opening an oil press to inject hydraulic oil into the conical surface area of the drawing die;

and (3) drawing the pipe in the pressure atmosphere of hydraulic oil.

8. The method for drawing a fine tube according to claim 7, wherein an oil press is connected to an oil inlet of an annular oil groove formed in the tapered surface region of the drawing die by a guide pipe; an overflow valve of the oil press is connected with an oil outlet of an annular oil groove on the conical surface area of the drawing die through a guide pipe; placing one end of a pipe to be drawn into a feeding opening of the drawing die; opening an oil press to inject hydraulic oil into the annular oil groove; the overflow valve controls the speed of hydraulic oil flowing through the annular groove; and (3) drawing the pipe in the pressure atmosphere of hydraulic oil.

Technical Field

The invention relates to the technical field of metal pipe precision machining, in particular to a drawing die and a drawing method for a micro-fine pipe.

Background

Aiming at the problems that the friction force accounts for a large proportion in the drawing process of a micro-fine tube, so that the drawing force is large, the tube is easy to break in the drawing process, the deformation of each pass is limited, the number of drawing passes is large, and the number of times of annealing among passes is large; multiple heat treatment is needed in the middle, the efficiency is low, and the cost is high.

The area where deformation occurs in the drawing process is mainly concentrated in the conical surface area, wall reduction and diameter reduction of the pipe occur, the drawing force, the positive pressure of the conical surface area on the pipe and the friction force between the outer wall of the pipe and a mold are mainly used in the area, and if the drawing process is the drawing process with the core rod, the friction force between the core rod and the inner wall of the pipe is also used. For the drawing of the core rod, the friction force accounts for a large amount of the total drawing force, sometimes the friction force accounts for 60%, and the maximum friction force in the empty drawing process also can reach 40%, so that the drawing force is obviously improved, and the tube breakage is easy to occur in the tube drawing process.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a drawing die and a drawing method for a micro-fine pipe, so that the single-pass deformation of the pipe is improved, the drawing passes are reduced, and the drawing process efficiency is improved.

In order to solve the technical problems, the technical scheme of the invention is as follows:

a drawing die for a fine pipe material, comprising:

a drawing die main body, wherein one end of the drawing die main body is provided with a pipe material inlet,

a pipe material outlet is symmetrically arranged with the material inlet;

a drawing channel communicating the feeding port and the discharging port,

a conical surface area close to the feeding opening is arranged on the drawing channel;

the conical surface area is provided with an annular oil groove or N oil injection holes, N is larger than or equal to 1, and the pipe is extruded and lubricated by injecting oil into the annular oil groove or the N oil injection holes.

Optionally, a sizing belt is arranged on the drawing channel and adjacent to the conical surface area; the annular oil groove or the N oil holes in the conical surface area are close to the bearing belt.

Optionally, the number and the position of the oil filling holes are adjustable according to the size of the pipe to be drawn.

Optionally, an oil inlet and an oil outlet are arranged on the annular oil groove; the oil inlet hole with the oil outlet hole symmetry sets up.

Optionally, the oil inlet is communicated with the oil press through a guide pipe, and an overflow valve is fixedly connected to the guide pipe connected with the oil outlet.

Optionally, the N oil injection holes are distributed on the same plane of the conical surface area; or at least one oil filling hole and the rest oil filling holes in the N oil filling holes are distributed on different planes of the conical surface area.

A drawing method of a micro-fine pipe material using the drawing die as described above, the method comprising:

connecting an oil press with an oil filling hole in the conical surface area of the drawing die by using a guide pipe;

placing one end of a pipe to be drawn into a feeding opening of the drawing die;

opening an oil press to inject hydraulic oil into the conical surface area of the drawing die;

and (3) drawing the pipe in the pressure atmosphere of hydraulic oil.

Optionally, a guide pipe is used for connecting an oil press with an oil inlet hole of an annular oil groove on the conical surface area of the drawing die; an overflow valve of the oil press is connected with an oil outlet of an annular oil groove on the conical surface area of the drawing die through a guide pipe; placing one end of a pipe to be drawn into a feeding opening of the drawing die; opening an oil press to inject hydraulic oil into the annular oil groove; the overflow valve controls the speed of hydraulic oil flowing through the annular groove; and (3) drawing the pipe in the pressure atmosphere of hydraulic oil.

The scheme of the invention at least comprises the following beneficial effects:

according to the scheme, the oil filling hole or the annular oil groove is formed in the conical surface area of the drawing die, and hydraulic oil is filled into the oil filling hole or the annular oil groove, so that the friction force in the drawing process is reduced, the single-pass deformation can be increased, the drawing passes can be reduced, and the drawing efficiency can be improved.

Drawings

FIG. 1 is a schematic cross-sectional view of a drawing die of the present invention;

FIG. 2 is a schematic view of an alternative embodiment of the present invention;

FIG. 3 is a schematic view of an alternative embodiment of the annular oil sump of the present invention;

fig. 4 is a schematic diagram of an alternative embodiment of the present invention.

The reference numbers illustrate: 1. drawing the die main body; 2. a pipe to be drawn; 3. a feeding port; 4. a discharge port; 5. a conical surface area; 6. an oil filler hole; 7. a sizing band; 8. an oil inlet hole; 9. an oil outlet hole; 10. an annular oil groove; 11 a conduit; 12. an oil pressure gauge; 13. an oil press; 14. an overflow valve; 15. and (4) drawing direction.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

As shown in fig. 1, an embodiment of the present invention provides a drawing die for a micro tube, the drawing die including: the drawing die comprises a drawing die body 1, wherein a pipe feeding port 3 is formed in one end of the drawing die body 1, and a pipe discharging port 4 is symmetrically formed with the pipe feeding port 3; the drawing channel is communicated with the feeding port 3 and the discharging port 4, and a conical surface area 5 close to the feeding port 3 is arranged on the drawing channel; the conical surface area 5 is provided with an annular oil groove 10 or N oil injection holes 6, N is larger than or equal to 1, and the pipe is extruded and lubricated by injecting oil into the annular oil groove 10 or the oil injection holes 6.

In the embodiment, the drawing die main body 1 is provided with a drawing channel penetrating through the whole die, one end of the drawing channel is provided with a feeding port 3, and a discharging port 4 is symmetrical to the feeding port 3 and is positioned at the other end of the drawing channel; the drawing channel is provided with a conical surface area 5 close to the feeding port 3, the conical surface area 5 is provided with an annular oil groove 10 or N oil injection holes 6, wherein N is more than or equal to 1, when the pipe is drawn, hydraulic oil is injected into the annular oil groove 10 or the N oil injection holes 6, the pipe wall of the pipe is separated from the conical surface area 5 by a certain amount by using the pressure of the hydraulic oil, if the pressure of the hydraulic oil is large enough, the pipe can be subjected to a certain amount of plastic deformation, which is equivalent to that the pipe is subjected to a certain amount of deformation before drawing, so that the single-pass deformation is increased, the drawing pass is reduced, and the drawing efficiency is improved; meanwhile, the friction force between the pipe and the conical surface area 5 can be reduced due to the existence of hydraulic oil, the drawing force is further reduced, and the pipe breakage in the drawing process is avoided.

In an alternative embodiment of the invention, a bearing band 7 is arranged on the drawing channel adjacent to the conical surface area 5; the annular oil groove 10 or the oil filling opening 6 is located close to the bearing band 7.

In this embodiment, the tapered surface area 5 and the bearing diameter 7 are sequentially arranged on the drawing passage, the tapered surface area 5 and the bearing diameter 7 are arranged adjacent to each other, the annular oil groove 10 or the oil injection hole 6 arranged on the tapered surface area 5 should be located close to the bearing diameter 7, and in the process of drawing the pipe, hydraulic oil is injected into the annular groove 10 or the oil injection hole 6 to reduce the friction force on the bearing diameter 7 side, so as to reduce the drawing force.

In an alternative embodiment of the invention, the number and position of the oil holes 6 are adjustable according to the dimensions of the tubular product 2 to be drawn. In this embodiment, the number and the position of the oil injection holes 6 can be adjusted according to the pipe diameter of the pipe 2 to be drawn. If the size of the pipe to be drawn is large, the contact area between the conical surface area 5 and the pipe 2 to be drawn is large, the number of the oil filling holes 6 can be more, the number of the corresponding oil filling holes 6 can be more, and the positions for arranging the oil filling holes 6 can be more selected; if the size of the pipe 2 to be drawn is small, the contact area between the conical surface area 5 and the pipe 2 to be drawn is small, the number of the oil filling holes 6 can be small, the number of the corresponding oil filling holes 6 can be small, and the position for setting the oil filling holes 6 is small.

Optionally, the N oil holes are distributed on the same plane of the conical surface area 5, or some of the N oil holes are distributed on the same plane of the conical surface area 5, and another part of the N oil holes are distributed on different planes of the conical surface area 5, or all of the N oil holes are distributed on different planes of the conical surface area 5. In this embodiment, the oil holes 6 are preferably distributed on the same plane of the conical surface section 5. Optionally, the N oil holes may be uniformly distributed, such as: when setting up 3 oil filler holes, 120 degrees in interval between two liang, when setting up 4 oil filler holes, hole interval 90 degrees between two liang, certainly N oil filler hole also can uneven distribution.

In an alternative embodiment of the present invention, the annular oil groove 10 is explained as follows: an oil inlet hole 8 and an oil outlet hole 9 are formed in the annular oil groove 10; the oil inlet hole 8 and the oil outlet hole 9 are symmetrically arranged.

As shown in fig. 3, in this embodiment, the oil inlet 8 and the oil outlet 9 are preferably symmetrically disposed on the annular oil groove 10, and the positions of the oil inlet 8 and the oil outlet 9 are not limited to be symmetrically disposed, but may be asymmetrically disposed. Optionally, the oil inlet 8 is communicated with an external oil press 13 through a guide pipe 11, and the oil press 13 injects hydraulic oil into the annular oil groove 10 through the oil inlet 8 through the guide pipe 11; an overflow valve 14 for controlling the flow rate and the flow velocity of hydraulic oil is fixedly connected to the conduit 11 connected with the oil outlet 9, the amount of the hydraulic oil is controlled by the overflow valve 14, so that the pressure of the hydraulic oil in the annular oil groove 10 is changed, the extrusion effect of the pipe 2 to be drawn is realized, meanwhile, the hydraulic oil is in direct contact with the pipe 2 to be drawn, the friction force between the pipe 2 to be drawn and the conical surface area 5 is reduced, and further the drawing force is reduced.

The embodiment of the invention also provides a drawing method of the micro-fine pipe, which applies the drawing die and comprises the following steps: connecting an oil press 13 with an oil filling hole 6 on the conical surface area 5 of the drawing die by using a guide pipe 11; one end of a pipe 2 to be drawn is placed into a feeding opening 3 of the drawing die; opening an oil press 13 to inject hydraulic oil into the conical surface area 5 of the drawing die; and (3) drawing the pipe in the pressure atmosphere of hydraulic oil.

As shown in fig. 2, in this embodiment, the oil injection hole 6 is connected to an external oil press 13 through a conduit 11, in the process of drawing the pipe, the oil press 13 is opened, hydraulic oil is injected into the tapered surface region 5, a certain pressure is applied to the pipe 2 to be drawn through the injected hydraulic oil, so that a certain amount of the pipe wall of the pipe 2 to be drawn is separated from the tapered surface region 5 of the die, the amount of the hydraulic oil injected is changed, the pressure of the pipe 2 to be drawn is changed, when the pressure is high enough, the pipe 2 to be drawn can be plastically deformed by a certain amount, which is equivalent to that the size of the pipe 2 to be drawn is reduced in the subsequent drawing process, and further, the amount of single deformation is increased, the number of drawing passes is reduced, the number of intermediate heat treatments is reduced, and the drawing process efficiency is improved; meanwhile, the injected hydraulic oil is directly contacted with the pipe 2 to be drawn, so that the friction force between the outer wall of the pipe 2 to be drawn and the die can be reduced, the friction force is further reduced, and the pipe is prevented from being broken in the drawing process.

As shown in fig. 4, an oil press 13 is connected with an oil inlet 8 of an annular oil groove 10 on the conical surface area 5 of the drawing die by a conduit 11; an overflow valve 14 of the oil press 13 is connected with an oil outlet 9 of an annular oil groove 10 on the drawing die conical surface area 5 through a guide pipe 11, so that an oil inlet and outlet passage is formed; one end of a pipe 2 to be drawn is placed into a feeding opening 3 of the drawing die; opening an oil press 13 to inject hydraulic oil into the annular oil groove 10 through an oil inlet hole 8; the overflow valve 14 controls the amount and the speed of hydraulic oil flowing into the annular oil groove 10, so that the hydraulic oil exerts a certain pressure on the pipe 2 to be drawn, and meanwhile, the injected hydraulic oil directly contacts with the pipe 2 to be drawn, so that the pipe 2 to be drawn is lubricated and drawn under the pressure and the lubrication of the hydraulic oil.

Optionally, if the requirement on the oil pressure is not high, the hydraulic oil can be heated, so that the pipe 2 to be drawn is locally heated, the deformation is facilitated, a mold can be heated, and the drawing force can be reduced; when a pipe made of materials such as magnesium alloy and the like is drawn, dynamic recrystallization can be generated by heating, so that crystal grains are refined and the structure is improved;

while the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.