CN107878564A - A kind of tubing and its manufacture method - Google Patents

Abstract

The invention relates to the field of pipe materials, and discloses a pipe material and a manufacturing method thereof. The pipe material includes a pipe piece and at least one built-in reinforcement, the pipe piece is an integral tubular structure, and the built-in reinforcement is a reinforcement structure arranged inside the pipe piece and in contact with the inner surface of the pipe piece. The pipe material provided by the invention can greatly improve the mechanical properties of the product without increasing the peripheral volume, and is an integrated product with intact surface effect and excellent mechanical properties.

Description

A kind of pipe and its manufacturing method

technical field

The invention relates to the field of pipes, in particular to a pipe, a method for manufacturing the pipe and a pipe manufactured by the method.

Background technique

Reducing the weight of automobiles and airplanes is one of the main measures to reduce energy consumption and pollution emissions. The main way to reduce weight is to use lightweight materials and lightweight structures. Lightweight materials include aluminum alloys, magnesium alloys, and composite materials. The main forms of light-weight structures include integral structures, thin shells, and hollow variable sections. For hollow parts with variable cross-section, the traditional manufacturing process is generally to stamp two halves first, and then weld them into a whole. This process is not only complicated in process, but also difficult to guarantee in quality. The internal high pressure forming is especially suitable for forming hollow variable cross-section parts. During internal high-pressure forming, the tube blank is deformed under the joint action of the internal high-pressure liquid and the axial load at both ends, and finally fits the molded part, thereby obtaining the required geometric shape of the part. Among them, the obtained formed part The shape can be controlled by controlling the internal shape of the mold. Compared with the traditional hollow member manufacturing process of stamping and welding, the internal high pressure forming process has obvious advantages. Internal high pressure forming technology has high production efficiency, fewer processes, and high rigidity of parts and components. Therefore, it is widely used in the fields of automobiles, aviation, and aerospace. Especially today, the demand for lightweight automobiles is increasing. higher demand. However, internal high pressure forming is mainly based on hollow pipes for variable cross-section forming. It cannot have structural features such as multiple support ribs and beams in the hollow section of industrial or architectural profiles. In some parts with particularly high performance requirements, there are strength and stiffness. Insufficient defects.

For this reason, scientific research workers have also made corresponding improvements to the tube beam structure obtained by internal high pressure forming to enhance its rigidity and strength. For example, CN102267490A discloses an automobile side member based on internal high pressure forming and a manufacturing method thereof. The automobile longitudinal beam based on internal high pressure forming is composed of a pipe fitting A1 and a reinforcing member A2. The pipe fitting A1 is an integral tubular structure, which is used to ensure the matching size requirements of various parts of the automobile longitudinal beam. The cross section of the reinforcing member A2 is concave. Grooved or rectangular, fixed on the outer surface of the middle part of the pipe fitting A1, used to enhance the rigidity and strength of the pipe fitting A1. The manufacturing method of the automobile longitudinal beam based on internal high pressure forming includes the following steps in order: (1) using the pipe material as a blank to make a preform of the pipe fitting A1 by means of a press bending or numerical control bending process; (2) making the above pipe fitting A1 (3) Use the plate as the blank to make the reinforced part A2 with a groove-shaped cross-section by stamping process, or use the pipe as the blank to make the cross-section A2 by the internal high-pressure forming method. Rectangular reinforcement A2; (4) Place the reinforcement A2 on the outer surface of the middle part of the pipe A1. If the cross-section of the reinforcement A2 is groove-shaped, make the opening on the side fit on the pipe A1. If the reinforcement A2 The cross-section of A2 is rectangular, so that the side where one long side is located is attached to the pipe fitting A1, and then the two are fixed by lap joints, butt joints, glue joints or mortise joints. This patent application uses pipe fittings made by internal high pressure forming as the main part of the longitudinal beam, and at the same time, reinforcements are provided outside the main part to increase the rigidity and strength of the pipe fittings, as much as possible under the premise of keeping the rigidity and strength of the longitudinal beam to meet the requirements Use a thinner wall thickness. However, this product has the following disadvantages: there are a large number of welding seams on the periphery of the product, which affects the appearance; the reinforcement is placed outside the inner high-pressure formed pipe beam and connected by welding, so the volume is large, and the application range of the product with limited space is limited.

Contents of the invention

The object of the present invention is to provide a new pipe, a method for manufacturing the pipe and the pipe manufactured by the method.

Specifically, the present invention provides a pipe, wherein the pipe includes a pipe and at least one built-in reinforcement, the pipe is an integral tubular structure, and the built-in reinforcement is arranged inside the pipe and is compatible with the The strengthening structure of the inner surface contact of the pipe fittings.

The present invention also provides a method for manufacturing a pipe. The method includes forming a pipe blank by internal high-pressure forming to obtain a pipe, and then placing at least one built-in reinforcement in the pipe, and welding the outer surface of the pipe. The built-in reinforcing member is fixed on the inner surface of the pipe by means of.

In addition, the present invention also provides the pipe produced by the above method.

The manufacturing method of the pipe material provided by the present invention is based on the internal high pressure forming, and built-in reinforcements such as reinforcing beams are fixed in the parts that need to be reinforced, and then the built-in reinforcements and the pipe are welded into one by welding on the outside of the pipe. A complete integral part, so that the obtained pipe can greatly improve the mechanical properties and the surface effect is intact without increasing the peripheral volume.

Other features and advantages of the present invention will be described in detail in the detailed description that follows.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the description, together with the following specific embodiments, are used to explain the present invention, but do not constitute a limitation to the present invention. In the attached picture:

Fig. 1 is a kind of concrete structure schematic diagram of tube blank;

Fig. 2 is a kind of specific structural representation of the tube blank after preforming;

Fig. 3 is a schematic diagram of a specific structure of the pipe, wherein the reinforcement is built into the cross-section A-A of the pipe obtained by internal high pressure forming;

Figure 4 is a cross-sectional view of the pipe at A-A, and the irregular parts in the oval pipe are built-in reinforcements.

Detailed ways

Specific embodiments of the present invention will be described in detail below. It should be understood that the specific embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

Neither the endpoints nor any values of the ranges disclosed herein are limited to such precise ranges or values, and these ranges or values are understood to include values approaching these ranges or values. For numerical ranges, between the endpoints of each range, between the endpoints of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, these values Ranges should be considered as specifically disclosed herein.

The pipe material provided by the present invention includes a pipe fitting and at least one built-in reinforcing member. The pipe fitting is an integral tubular structure, and the built-in reinforcing member is a reinforcing structure arranged inside the pipe fitting and in contact with the inner surface of the pipe fitting.

The pipe fittings may be hollow constant-section pipe fittings, hollow variable-section pipe fittings, or composite pipe fittings of part hollow constant-section pipe fittings and part hollow variable-section pipe fittings. When there is a hollow variable cross-section part in the pipe fitting, the change of the cross-section of the pipe fitting can be designed according to the needs of actual use, and can be controlled by the shape of the mold during the pipe fitting forming process. In addition, the cross section of the pipe can be various existing shapes, for example, it can be circular, square, triangular and other irregular shapes. Those skilled in the art are well aware of this, so details are not repeated here.

There can be one or more built-in reinforcements, and they can be arranged on the inner surface of the tube where reinforcement is required. The built-in reinforcing member can be arranged on a part of the inner surface of the pipe along the length direction of the pipe, or it can be arranged on the entire inner surface of the pipe along the length of the pipe, and it should also be determined according to the length of the reinforced position. Definitely, this is known to those skilled in the art and will not be repeated here.

The built-in reinforcement may be a reinforcement beam. Only one reinforcement beam may be provided at the same cross-section of the pipe fitting, or multiple reinforcement beams may be provided. When multiple reinforcement beams are provided on the same cross section of the pipe, at least part of each reinforcement beam is in contact with the inner surface of the pipe, and different reinforcement beams can be arranged alternately, and the specific arrangement form is not particularly limited.

The present invention has no particular limitation on the material of the pipe fitting and the built-in reinforcing member, which may be the same or different, and may be various existing steel materials and/or light alloys independently. As is well known to those skilled in the art, the term "steel" refers to a material with high hardness, good high temperature resistance, good processability and high specific gravity. The term "lightweight alloy" refers to an alloy material with low hardness and light weight (density below 5.0 g/cm ³ ). The categories to which both belong are known to those skilled in the art. From the perspective of wide application, the steel is preferably stainless steel and/or carbon steel, and the light alloy is preferably at least one of magnesium alloy, aluminum alloy and titanium alloy.

The present invention has no particular limitation on the wall thickness of the pipe fitting, which can generally be selected according to actual use requirements. For example, the wall thickness of the pipe fitting can be 1-20 mm, preferably 1-10 mm.

The manufacturing method of the pipe provided by the present invention comprises the steps of forming a pipe blank by internal high pressure forming to obtain a pipe, then placing at least one built-in reinforcement in the pipe, and welding the built-in reinforcement to the outer surface of the pipe. A piece is fixed on the inner surface of the pipe.

As mentioned above, there may be one or more built-in reinforcing members, and they may be arranged on the inner surface of the pipe fitting where reinforcement is required by means of welding. The built-in reinforcing member can be arranged on a part of the inner surface of the pipe along the length direction of the pipe, or it can be arranged on the entire inner surface of the pipe along the length of the pipe, and it should also be determined according to the length of the reinforced position. Sure. Furthermore, the built-in reinforcement may be a reinforcement beam. At this time, only one reinforcement beam may be provided by welding at the same cross section of the pipe fitting, or multiple reinforcement beams may be provided by welding. When multiple reinforcement beams are provided on the same cross section of the pipe, at least part of each reinforcement beam is in contact with the inner surface of the pipe, and different reinforcement beams can be arranged alternately, and the specific arrangement form is not particularly limited.

When the built-in reinforcement is fixed by welding, the corresponding surface of the pipe and the welding spot of the built-in reinforcement are melted during the welding process, and after the temperature drops, the pipe and the built-in reinforcement form a whole.

The present invention has no particular limitation on the materials of the tube blank and the built-in reinforcement, which may be the same or different, and may be various existing steel materials and/or light alloys independently. As mentioned above, the term "steel" refers to a material with high hardness, good high temperature resistance, good processability and high specific gravity. The term "lightweight alloy" refers to a low hardness, light weight (density below 5.0 g/cm ³ ) alloy material. The categories to which both belong are known to those skilled in the art. From the perspective of wide application, the steel is preferably stainless steel and/or carbon steel, and the light alloy is preferably at least one of magnesium alloy, aluminum alloy and titanium alloy.

The present invention has no particular limitation on the wall thickness of the tube blank, which can generally be selected according to actual use requirements. For example, the wall thickness of the tube blank can be 1-20 mm, preferably 1-10 mm. In addition, the cross section of the tube blank can be various existing shapes, for example, it can be circular, square, triangular and other irregular shapes.

According to the pipe manufacturing method provided by the present invention, the specific operation process of the internal high pressure forming is well known to those skilled in the art. For example, the method of internal high pressure forming includes putting the tube blank into a mold, closing the mold, and then contacting and sealing the two ends of the tube blank with sliding punches, and then injecting the tube blank into the tube blank The liquid medium deforms the tube blank by controlling the axial load of the sliding punch and the pressure of the liquid medium. The tube blank is deformed under the joint action of the axial load at both ends provided by the sliding punch and the high-pressure liquid medium, and finally fits the mold, thereby obtaining parts with required geometric shapes.

The present invention does not specifically limit the type and pressure of the liquid medium, as long as the tube blank can be deformed under the joint action of the liquid medium and the axial load at both ends provided by the sliding punch and finally fit the mold That's it. For example, the liquid medium may be at least one of high-pressure water, hydraulic oil, emulsion, etc., and is preferably high-pressure water from the viewpoints of availability of raw materials and environmental protection. The pressure of the liquid medium may be 0-500MPa, preferably 50-400MPa, most preferably 50-300MPa. In the present invention, the pressure refers to gauge pressure.

According to the pipe manufacturing method provided by the present invention, the internal high pressure forming process can be carried out at normal temperature or at high temperature, preferably at high temperature. When the internal high pressure forming process is performed at a high temperature, the forming performance of the tube blank can be improved, thereby obtaining a complex large-deformation tube material. In addition, the high temperature can be provided by a mold, or by a liquid medium, or both. According to a preferred embodiment of the present invention, the temperature of the liquid medium is 20-500°C, more preferably 30-400°C, most preferably 40-300°C; the temperature of the mold is 20-500°C, more preferably Preferably it is 30-400°C, most preferably 40-300°C.

In addition, the pipes to be prepared can be straight pipes or curved pipes. When the pipe to be prepared is a bent pipe, the manufacturing method of the pipe may further include bending and preforming the tube blank by using a press bending or numerical control bending process before adopting internal high pressure forming, and then preforming the preformed tube blank Perform high pressure forming.

According to a preferred embodiment of the present invention, the manufacturing method of the pipe further includes polishing the outer surface of the pipe after fixing the built-in reinforcement on the inner surface of the pipe, so that the The outer surface of the pipe is smooth and the appearance is beautiful.

According to a specific embodiment of the present invention, as shown in Fig. 1-Fig. 4, the manufacturing method of the pipe includes: bending and preforming the pipe blank shown in Fig. 1 by bending or numerically controlled bending process, to obtain Fig. The preformed tube blank shown in the figure is followed by internal high pressure forming to obtain a tube, and then the built-in reinforcements formed by reinforcing beams are placed inside the tube, and these built-in reinforcements are fixed to the tube by welding on the outer surface of the tube On the inner surface of the pipe fitting, the outer surface of the pipe fitting is polished and polished, and the obtained pipe is shown in Figure 3, wherein the reinforcing beam is located at the cross section A-A of the pipe fitting, and the specific structure is shown in Figure 4.

In addition, the present invention also provides the pipe produced by the above method.

The present invention will be described in detail below by way of examples.

Example 1

This embodiment is used to illustrate the pipe provided by the present invention and its manufacturing method.

A seamless stainless steel pipe (circular in cross section, 103 mm in outer diameter, and 2 mm in wall thickness) was used as a tube blank. Preformed by bending process to obtain preformed tube blank. Then put the preformed tube blank into the mold (at a temperature of 120°C), close the mold, the two ends of the preformed tube blank and the sliding punch connected with the pipeline are sealed by high pressure, and then pass the pipeline to the preformed tube. High-pressure water with a pressure of 50MPa and a temperature of 80°C is injected into the billet. By controlling the axial load of the sliding punch to 50 MPa and the pressure of high-pressure water to 50 MPa, the preformed tube blank is deformed to obtain a tube fitting. Then the reinforcement (obtained by setting four reinforcement beams in a well-shaped shape, the circumference (that is, the inner circumference of the pipe fitting at the place where the reinforcement is set, the same below) is about 280mm, the length is 180cm, the material is carbon steel, and the width of each reinforcement beam 2mm) built into the cross-section A-A of the pipe fitting, weld the outer surface of the pipe fitting to fix the four reinforcing beams on the inner surface of the pipe fitting, and then polish the outer surface of the pipe fitting to obtain a good surface effect The integrated pipe G1 has a wall thickness of 1.95 mm. According to GB/T244-1997 metal pipe bending test method, the bending resistance of the pipe G1 at the cross section A-A is 60KN.

Example 2

This embodiment is used to illustrate the pipe provided by the present invention and its manufacturing method.

A seamless magnesium alloy tube (circular in cross section, 128 mm in outer diameter, and 4 mm in wall thickness) was used as a tube blank. Preformed by bending process to obtain preformed tube blank. Then put the preformed tube blank into the mold (at a temperature of 400°C), close the mold, the two ends of the preformed tube blank and the sliding punch connected with the pipeline are sealed by high pressure, and then pass the pipeline to the preformed tube. High-pressure water with a pressure of 130MPa and a temperature of 150°C is injected into the billet. By controlling the axial load of the sliding punch to 30 MPa and the pressure of high-pressure water to 130 MPa, the preformed tube blank is deformed to obtain a tube fitting. Then the reinforcement (obtained by four reinforcement beams arranged in a well-shaped shape, with a circumference of about 330mm and a length of 200cm, made of magnesium alloy, and the width of each reinforcement beam is 2mm) is built into the cross section A-A of the pipe fitting. The outer surface of the pipe is welded to fix the four reinforcing beams on the inner surface of the pipe, and then the outer surface of the pipe is polished to obtain an integrated pipe G2 with a good surface effect, and its wall thickness is 1.95mm. According to GB/T244-1997 metal pipe bending test method, the bending resistance of the pipe G2 at the cross section A-A is 46KN.

Example 3

This embodiment is used to illustrate the pipe provided by the present invention and its manufacturing method.

A seamless aluminum alloy tube (circular in cross section, 94 mm in outer diameter, and 2 mm in wall thickness) was used as a tube blank. Preformed by bending process to obtain preformed tube blank. Then put the preformed tube into the mold (at a temperature of 250°C), close the mold, and seal the two ends of the preformed tube with the sliding punch connected to the pipeline, and then pass the pipeline to the preformed tube. High-pressure water with a pressure of 80MPa and a temperature of 50°C is injected into the billet. By controlling the axial load of the sliding punch to 20 MPa and the pressure of high-pressure water to 80 MPa, the preformed tube blank is deformed to obtain a tube fitting. Then the reinforcement (obtained by four reinforcement beams arranged horizontally and equidistantly in parallel, the circumference is about 250mm, the length is 150mm, the material is aluminum alloy, and the width of each reinforcement beam is 2mm) is built into the cross-section A-A of the pipe fitting , welding is performed on the outer surface of the pipe fitting to fix the four reinforcing beams on the inner surface of the pipe fitting, and then the outer surface of the pipe fitting is polished and polished to obtain an integrated pipe G3 with a good surface effect, and its wall thickness is 1.95mm. According to the GB/T244-1997 metal pipe bending test method, the bending resistance of the pipe G3 at the cross section A-A is 50KN.

Comparative example 1

This comparative example serves to illustrate a reference pipe and its method of manufacture.

The pipe was manufactured according to the method of Example 1, except that the step of setting the built-in reinforcement was not included, and the pipe DG1 was obtained. According to GB/T244-1997 metal pipe bending test method, the bending resistance of the pipe DG1 at the cross section A-A is 39KN.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention. These simple modifications All belong to the protection scope of the present invention.

In addition, it should be noted that the various specific technical features described in the above specific implementation manners may be combined in any suitable manner if there is no contradiction. In order to avoid unnecessary repetition, various possible combinations are not further described in the present invention. In addition, various combinations of different embodiments of the present invention can also be combined arbitrarily, as long as they do not violate the idea of the present invention, they should also be regarded as the disclosed content of the present invention.

Claims (12)

1. A pipe, characterized in that the pipe includes a pipe and at least one built-in reinforcement, the pipe is an integral tubular structure, and the built-in reinforcement is arranged inside the pipe and connected to the inside of the pipe Enhanced structure for surface contact. 2. The pipe according to claim 1, wherein the materials of the pipe and the built-in reinforcement are each independently selected from at least one of stainless steel, carbon steel, magnesium alloy, aluminum alloy and titanium alloy. 3. The pipe according to claim 1 or 2, wherein the wall thickness of the pipe is 1-20mm. 4. The pipe according to claim 1 or 2, wherein the built-in reinforcement is a reinforcing beam. 5. A method for manufacturing a pipe, the method comprising forming a pipe blank by internal high pressure forming to obtain a pipe, then placing at least one built-in reinforcement in the pipe, and welding the pipe on the outer surface of the pipe The built-in reinforcement is fixed on the inner surface of the pipe. 6. The manufacturing method according to claim 5, wherein the material of the tube blank and the built-in reinforcement is independently selected from at least one of stainless steel, carbon steel, magnesium alloy, aluminum alloy and titanium alloy. 7. The manufacturing method according to claim 5, wherein the built-in reinforcement is a reinforcement beam. 8. The manufacturing method according to any one of claims 5-7, wherein the method of internal high pressure forming comprises putting the tube blank into a mold, closing the mold, and then placing the two tube blanks The end is in contact with the sliding punch and sealed, and then a liquid medium is injected into the tube blank, and the tube blank is deformed by controlling the axial load of the sliding punch and the pressure of the liquid medium. 9. The manufacturing method according to claim 8, wherein the pressure of the liquid medium is 0-500 MPa; the temperature of the liquid medium and the mold are each independently 20-500°C. 10. The manufacturing method according to any one of claims 5-7, wherein when the thickness of the tube blank is 1-20mm. 11. The manufacturing method according to any one of claims 5-7, wherein the method further comprises polishing the outer surface of the tubular member after fixing the built-in reinforcement on the inner surface of the tubular member polished. 12. A pipe produced by the method of any one of claims 5-11.