TWI663004B - System and method for producing metal forming tube - Google Patents

Abstract

The invention provides a metal pipe fitting forming system and method. The system includes a mold and a pair of clamps. The mold includes an upper mold and a lower mold. When the upper mold and the lower mold are closed, a cavity is formed between the upper mold and the lower mold. ; When the metal pipe forming system executes a forming process, a metal round pipe is placed in the cavity, and the clamping parts of the two clamps enter the two sides of the metal round pipe to hold the metal round pipe. After that, a high-pressure gas passes through A gas channel in the clamp is injected into the metal round pipe so that the wall of the metal round pipe is adhered to the inner surface of the cavity to form a metal formed pipe with a special diameter or a pattern.

Description

   Metal pipe fitting forming system and method   

The invention relates to a metal pipe fitting forming system and method, in particular to a system and method for forming a metal pipe into a metal pipe with a special diameter or a metal pipe with a pattern.

Metal fittings are widely used in machinery, automobile, aerospace and other industries. A metal pipe is formed into a metal pipe with a specific shape by the metal pipe forming technology.

Please refer to FIG. 1 for a schematic diagram of a conventional metal pipe forming system. As shown in FIG. 1, the metal tube forming system 100 includes a mold 11 and a mandrel 13. The mold 11 includes an upper mold 111 and a lower mold 112. When the upper mold 111 and the lower mold 112 are combined, a cavity 113 exists between the upper mold 111 and the lower mold 112. The cavity 113 has an inlet 114, and the mandrel 13 includes a tapered portion 131. When the upper mold 111 and the lower mold 112 are combined, the mandrel member 13 is sandwiched in the cavity 113, and the tapered portion 131 of the mandrel member 13 is disposed at the entrance 114 of the cavity 113.

When the metal pipe forming system 100 executes a metal pipe forming process, a pushing member 14 pushes a heated metal round pipe 15 toward the inlet 114 of the cavity 113. When the metal circular tube 15 gradually enters the inside of the cavity 113 through the inlet 114, the wall of the metal circular tube 15 will be gradually opened by the tapered portion 131 of the mandrel member 13 and attached to the cavity 113. Then, the wall of the metal circular pipe 15 will match the shape of the cavity 113 to become a metal formed pipe.

In the conventional metal pipe forming system 100, the mold 11 mostly needs the cooperation of the mandrel 13 to perform the metal forming process on the metal round pipe 15, and the metal forming pipe produced through the metal round pipe 15 usually has a single shape. For example, the metal round pipe 15 is formed as a metal formed pipe with a part of a large round pipe diameter or a part of a small round pipe diameter.

In view of this, the present invention will provide an innovative metal tube forming system. The mold of the forming system can form a metal forming tube without the cooperation of an additional component (such as a mandrel), and the metal forming tube can be formed. It is an object of the present invention to have a plurality of shaped pipe diameters and / or texture patterns.

An object of the present invention is to provide a metal pipe fitting forming system and method, which can perform a forming process on a metal round pipe, so that the metal round pipe can be made into a metal shaped pipe fitting with a special-shaped pipe diameter and / or texture pattern.

An object of the present invention is to provide a metal pipe fitting forming system. The forming system uses a pair of clamps with tapered members to clamp a metal round pipe in a mold, and the two sides of the metal round pipe are to be tapered by the clamp The part is extruded into a trumpet shape, so that the lip-shaped nozzle of the metal round pipe and the conical part of the clamp show a sealed state. When a high-pressure gas for forming a metal round pipe passes through one of the clamps, When injecting into a metal pipe, high pressure gas can be prevented from leaking out of the nozzle of the metal pipe.

To achieve the above object, the present invention provides a metal pipe forming system, including: a mold, including an upper mold and a lower mold, when the upper mold and the lower mold are closed, a cavity is formed between the upper mold and the lower mold, wherein the mold The cross-section in the width direction of the cavity has a variety of contour shapes; and a pair of clamps, each of which is provided with a clamping portion on one side, at least one of which includes a gas input hole and a gas output hole, and the gas output hole is provided On the clamp part, a gas pipeline is arranged between the gas input hole and the gas output hole. Among them, when the metal pipe forming system performs a forming process, a metal round pipe is placed in the cavity, and the two clamps enter through the clamp part respectively. The metal round pipe is clamped in the two sides of the metal round pipe, and a high-pressure gas is injected into the metal round pipe through the gas input hole, the gas pipeline and the gas output hole to make the wall of the metal round pipe adhere to the cavity. It becomes a metal forming pipe with a special diameter.

In an embodiment of the present invention, the clamping portion is a tapered member. When the clamping portion enters the nozzle of the metal round pipe, the nozzle will be squeezed into a trumpet shape by the clamping portion.

In an embodiment of the present invention, the inner surface of the die cavity includes a texture pattern layer. When the wall of the metal circular tube is affixed to the texture pattern layer of the mold cavity by the pressure of high pressure gas, a mold is formed in the mold. Metal forming pipe fittings with irregular pipe diameter and grain pattern.

In an embodiment of the present invention, the metal round pipe is a metal round pipe of the same pipe diameter, a metal round pipe of a tapered pipe diameter, or a metal round pipe of a different pipe diameter.

In an embodiment of the present invention, the upper mold and the lower mold each have a half mold cavity, and the half mold cavity of the upper mold and the half mold cavity of the lower mold have symmetrical or asymmetrical contour structures.

In one embodiment of the present invention, at least one heater is provided inside or around the mold. When the metal pipe forming system executes the forming process, the heater will heat the mold to a predetermined temperature, and the predetermined temperature is 400-500 ° C.

In one embodiment of the present invention, the metal circular pipe is an aluminum-magnesium alloy, a titanium alloy, or other metal materials.

In one embodiment of the present invention, the pressure of the high-pressure gas is 50 to 200 kg / cm ² .

In an embodiment of the present invention, when the metal forming pipe has been formed in the mold, the clamping part of the clamp is withdrawn from the nozzles on both sides of the metal forming pipe and the mold is moved onto a cooling platform.

The invention also provides a metal pipe forming system, which includes a mold including an upper mold and a lower mold. When the upper mold and the lower mold are closed, there is a cavity between the upper mold and the lower mold, and an inner surface of the cavity The utility model comprises a texture pattern layer; and a pair of clamps, each of which has a clamp portion provided on one side, at least one of the clamps includes a gas input hole and a gas output hole, the gas output hole is provided on the clamp portion, and a gas tube The circuit is arranged between the gas input hole and the gas output hole. Among them, when the metal pipe fitting forming system executes a forming process, a metal round pipe is placed in the mold cavity, and the two clamps enter the two sides of the metal round pipe through the clips A metal round pipe is clamped, and a high-pressure gas is injected into the metal round pipe through a gas input hole, a gas pipeline, and a gas output hole, so that the wall of the metal round pipe is adhered to the pattern pattern layer of the cavity to have a Patterned metal forming pipe fittings.

The present invention also provides a method for forming a metal pipe. The steps include: placing a metal round pipe into a cavity of a mold; heating the mold to a preset temperature; and allowing the clamping portions of a pair of clamps to enter the two sides of the metal round pipe The metal round pipe is clamped in the mouth; the two sides of the metal round pipe are squeezed through the clamping part of the two clamps so that the two sides of the metal round pipe are squeezed into a horn state respectively; and a high-pressure gas is passed through at least A clamp is injected into the metal round pipe so that the wall of the metal round pipe is adhered to the inner surface of the cavity to become a metal formed pipe with a special diameter or a pattern.

In an embodiment of the present invention, a step is further included: the metal forming pipe is formed on the mold and moved to a cooling platform.

100‧‧‧Metal Pipe Forming System

11‧‧‧Mould

111‧‧‧ Upper mold

112‧‧‧ bottom die

113‧‧‧Mould cavity

13‧‧‧ mandrel

131‧‧‧ cone

14‧‧‧ Pusher

15‧‧‧Metal Round Tube

200‧‧‧Metal Pipe Forming System

21‧‧‧Mould

211‧‧‧Mould

212‧‧‧mould

22‧‧‧Mould cavity

23‧‧‧Fixture

231‧‧‧ Clamp

24‧‧‧ Fixture

241‧‧‧ Clamp

250‧‧‧ high pressure gas

251‧‧‧Gas input hole

252‧‧‧Gas pipeline

253‧‧‧Gas output hole

27‧‧‧heater

29‧‧‧Texture pattern layer

30‧‧‧Metal Round Tube

301‧‧‧ nozzle

31‧‧‧Metal forming pipe fittings

32‧‧‧Metal Round Tube

33‧‧‧Metal forming pipe fittings

331‧‧‧Texture pattern

Figure 1: Structural diagram of a conventional metal pipe forming system.

FIG. 2 is a structural perspective view of an embodiment when a mold of the metal pipe fitting forming system of the present invention is opened.

FIG. 3 is a structural perspective view of an embodiment when a mold of the metal pipe fitting forming system of the present invention is closed.

FIG. 4 is a structural schematic diagram of an embodiment when the mold of the metal pipe fitting forming system of the present invention is closed.

FIG. 5 is a schematic structural diagram of an embodiment when a high-pressure gas is injected into the metal pipe fitting forming system of the present invention.

FIG. 6 is a structural schematic diagram of an embodiment in which a mold of a metal pipe fitting forming system of the present invention is placed on a cooling platform.

Figure 7: A perspective view of the structure of the present invention for removing a metal forming pipe from a mold of the metal pipe forming system.

FIG. 8 is an enlarged sectional view of an embodiment of a cavity of a mold and a metal forming pipe fitting of the present invention.

FIG. 9 is an enlarged cross-sectional view of another embodiment of the cavity and the metal forming pipe of the mold of the present invention.

Fig. 10: The metal pipe forming system of the present invention uses a metal circle pipe with a gradual diameter change to make a metal forming pipe.

FIG. 11 is a structural perspective view of another embodiment of the upper mold / lower mold of the present invention.

FIG. 12 is a schematic structural diagram of another embodiment when a high-pressure gas is injected into the metal pipe fitting forming system of the present invention.

FIG. 13 is a structural perspective view of a metal forming pipe with a grain pattern according to the present invention.

Please refer to FIG. 2, FIG. 3, FIG. 4 and FIG. 5, which are structural perspective views of an embodiment when the mold of the metal pipe forming system of the present invention is opened, and an embodiment of the mold when the metal pipe forming system of the present invention is closed. A structural perspective view and a schematic diagram of the structure and a schematic diagram of an embodiment when a high-pressure gas is injected into the metal pipe fitting forming system of the present invention. As shown in these figures, the metal pipe forming system 200 of the present invention includes a mold 21 and a pair of clamps 23 and 24. The mold 21 includes an upper mold 211 and a lower mold 212. When the upper mold 211 and the lower mold 212 are closed, a cavity 22 is formed between the upper mold 211 and the lower mold 212. At least one heater 27 is provided inside or around the upper mold 211 and the lower mold 212, respectively. Clips 231 and 241 are provided on one side of each of the clamps 23 and 24. The clamp 23 includes a gas input hole 251 and a gas output hole 253. The gas output hole 253 is disposed on the clamp portion 231, and a gas pipeline 252 is disposed between the gas input hole 251 and the gas output hole 253.

As shown in FIGS. 3 and 4, when the metal pipe forming system 200 wants to perform a forming process on a metal round pipe 30, the upper die 211 and the lower die 212 are closed, and the metal round pipe 30 is set in the die of the die 21. Hole 22. The heater 27 executes a heating procedure for the mold 21 to heat the mold 21 to a predetermined temperature.

As shown in FIG. 5, when the mold 21 is heated to a predetermined temperature, the clamps 23 and 24 respectively enter the mouths 301 on both sides of the metal round pipe 30 through the clamping portions 231 and 241 to clamp the metal round pipe 30. After that, a high-pressure gas 250 is injected into the metal circular tube 30 through the gas input hole 251, the gas pipeline 252, and the gas output hole 253. Then, the tube wall of the metal circular tube 30 is affixed to the inner surface of the cavity 22 by the impact of the high-pressure gas 250, so that the metal circular tube 30 can be formed into a metal forming tube 31. In the present invention, the high-pressure gas 250 is an air or an inert gas, such as helium (He), neon (Ne), and nitrogen (N ₂ ).

In an embodiment of the present invention, the clamping portions 231-241 are a tapered member. When the clips 231 and 241 enter the nozzle 301 of the heated metal pipe 30, the nozzle 301 of the heated metal pipe 30 will be squeezed into a trumpet shape by the tapered clips 231 and 241. Then, the lip-shaped nozzle 301 and the tapered clip portions 231 and 241 will be in a sealed state. Then, due to the sealing effect generated between the nozzle 301 and the clamp portions 231 and 241, when the high-pressure gas 250 is injected into the metal round pipe 30, the high-pressure gas 250 can be prevented from leaking from the nozzle 301.

In one embodiment of the present invention, the metal pipe forming system 200 can use a metal tube 30 made of an aluminum-magnesium alloy (such as 6061, 6063, or 5083, but not limited to this) to produce metal forming.管 件 31。 Tube member 31. The metal pipe forming system 200 performs a predetermined temperature required for performing a forming process on the aluminum-magnesium alloy metal pipe 30 to be 400 to 500 ° C., and the pressure of the high-pressure gas 250 is 50 to 200 kg / cm ² . Alternatively, in another embodiment of the present invention, the metal pipe fitting forming system 200 also uses a pipe body of titanium alloy or other metal materials to make the metal forming pipe fitting 31, and the metal pipe fitting forming system 200 executes a predetermined temperature and high pressure required for the forming process. The pressure of the gas 250 will be appropriately adjusted according to the selection of metal round tubes 30 of different materials.

Subsequently, as shown in FIG. 6, the metal pipe forming system 200 of the present invention further includes a cooling platform 50. The cooling platform 50 includes a cooling circuit 501. When the metal forming pipe 31 has been formed in the mold 21, the clamping portions 231 and 241 of the clamps 23 and 24 will be withdrawn from the nozzles 301 on both sides of the metal forming pipe 31. The hot mold 21 will be moved above the cooling platform 50 to cool down the cooling platform 50. Thereafter, as shown in FIG. 7, if the mold 21 has cooled down, the mold 21 is opened, and the metal forming pipe 31 is taken out of the mold 21 to complete the forming process of the metal pipe.

Please refer to FIG. 8, which is an enlarged cross-sectional view of an embodiment of a cavity of a mold and a metal forming pipe fitting according to the present invention. The inner surface of the cavity 22 in this embodiment is a surface formed by a gradual contour shape. As shown in FIG. 8, a cross section is performed in the width direction of the cavity 22, and the outline shape of the inner surface of the cavity 22 is a small circle at the cross section position A1-A1 '; The contour shape of the inner surface of the cavity 22 is a large circle; at the cross-sectional position A3-A3 ', the contour shape of the interior surface of the cavity 22 is a round shape approximately hexagonal; at the cross-sectional position A4-A4', The outline shape of the inner surface of the cavity 22 is a hexagon; at the cross-sectional position A5-A5 ', the outline shape of the inner surface of the cavity 22 is an approximately hexagonal circle; at the cross-sectional position A6-A6', the cavity is The outline shape of the inner surface of 22 is a large circle; at the cross-sectional positions A7-A7 ', the outline shape of the inner surface of the cavity 22 is a small circle. Therefore, the inner surface of the cavity 22 in this embodiment is a surface composed of a gradual contour shape, for example, gradual change from a small circle and a large circle to a hexagon, and then gradual change from a hexagon and a large circle to a small circle. Then, the metal pipe fitting forming system 200 forms a metal shaped pipe fitting 31 with a tapered pipe diameter according to the tapered contour shape of the inner surface of the cavity 22.

Please refer to FIG. 9, which is an enlarged cross-sectional view of another embodiment of the cavity and the metal forming pipe of the mold of the present invention. The inner surface of the cavity 22 in this embodiment is a surface composed of various contour shapes. As shown in FIG. 9, A1-A1'-A7-A7 'sections are implemented in the width direction of the cavity 22, and the outline shape in the cavity 22 may also include a circle, a hexagon, a square, and the like. Then, according to various contour shapes in the cavity 22, the metal pipe forming system 200 is formed with various shapes of pipe diameters on the pipe body of the metal round pipe 30, such as round, hexagonal, and square pipe diameters, so that A shaped pipe member 31 with a special diameter.

Furthermore, the upper mold 211 and the lower mold 212 each have a half mold cavity, and the mold cavity 22 will be composed of a half mold cavity of the upper mold 211 and a half mold cavity of the lower mold 212. In an embodiment of the present invention, the half-mold cavity of the upper mold 211 and the half-mold cavity of the lower mold 212 have a symmetrical outline structure, so that the metal forming pipe piece 31 can be formed with a symmetrical pipe diameter structure. Alternatively, in another embodiment of the present invention, the half-mold cavity of the upper mold 211 and the half-mold cavity of the lower mold 212 have an asymmetric contour structure, so that the metal forming pipe member 31 can be formed with an asymmetric pipe diameter structure.

Please refer to FIG. 10, which is a schematic diagram of a metal tube forming system according to the present invention performing a forming process using a metal round pipe with a reduced diameter. As described above, the metal pipe forming system 200 can perform a forming process on a metal round pipe 30 having the same pipe diameter to produce a metal forming pipe 31. Alternatively, as shown in FIG. 10, the metal pipe fitting forming system 200 may also perform a forming procedure on a metal round pipe 32 having a tapered pipe diameter or a metal round pipe with a different pipe diameter to produce a metal shaped pipe fitting 31.

Please refer to FIG. 11 and FIG. 12, which are structural perspective views of another embodiment of the upper mold / lower mold of the present invention and schematic diagrams of another embodiment of the metal pipe forming system when a high-pressure gas is injected. As shown in FIG. 11 and FIG. 12, the upper mold 211 or the lower mold 212 of the mold 21 according to the present invention includes a half cavity 2111 or 2121. When the upper mold 211 and the lower mold 212 are closed, the half mold cavities 2111 and 2121 will be formed into the mold cavity 22. The inner surface of the cavity 22 includes a texture pattern layer 29. In the embodiment, the metal pipe forming system 200 performs a pattern forming process on the metal round pipe 30.

When the forming process of the texture pattern is performed on the metal circular tube 30, the upper mold 211 and the lower mold 212 are closed, and the metal circular tube 30 is set in the cavity 22 of the mold 21. The heater 27 executes a heating procedure for the mold 21, and the mold 21 is heated to a predetermined temperature. After the mold 21 is heated to a predetermined temperature, the clamps 23 and 24 respectively enter the mouths 301 on both sides of the metal circular pipe 30 via the clamping portions 231 and 241 to clamp the metal circular pipe 30. After that, the high-pressure gas 250 is injected into the metal circular pipe 30 through the gas input hole 251, the gas pipe 252, and the gas output hole 253. Then, the tube wall of the metal circular tube 30 is affixed to the texture pattern layer 29 of the die cavity 22 under the impact of the high-pressure gas 250 to form a metal forming pipe member 33 having a texture pattern 331. Next, the clamps 23 and 24 are withdrawn from both sides of the mold 21, and the mold 21 is moved to the cooling platform 50 to cool down. After the mold 21 having cooled down is opened, the metal forming pipe 33 having the pattern 331 can be taken out of the mold 21, as shown in FIG. 13.

Furthermore, the metal pipe fitting forming system 200 can also use the aluminum-magnesium alloy metal round pipe 30 to perform the pattern forming process. In addition, the predetermined temperature required for the metal pipe forming system 200 to perform the forming process of the texture pattern is 400 to 500 ° C., and the pressure of the high-pressure gas 250 is 50 to 200 kg / cm ² . Alternatively, in another embodiment of the present invention, the metal pipe fitting forming system 200 can also select a metal round pipe 30 made of titanium alloy or other metal materials to perform the pattern forming process.

Of course, in another embodiment of the present invention, the inner surface of the cavity 22 of the mold 21 has multiple contour shapes and texture pattern layers 29 simultaneously, so that the metal pipe forming system 200 can form a texture pattern through the cavity 22 And a metal-shaped pipe fitting 33 with a special-shaped pipe diameter.

The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of implementation of the present invention, that is, any change in shape, structure, characteristics, and spirit according to the scope of the patent application for the present invention is equivalent to Modifications shall be included in the scope of patent application of the present invention

Claims (15)

A metal pipe fitting forming system includes a mold including an upper mold and a lower mold. When the upper mold and the lower mold are closed, a cavity is formed between the upper mold and the lower mold, and a width of the cavity is formed. The cross section in the direction has a variety of contour shapes; and a pair of clamps, each of which is provided with a clamp portion on one side, at least one of the clamps includes a gas input hole and a gas output hole, and the gas output hole is provided A gas pipeline is disposed between the gas input hole and the gas output hole on the clamping portion; wherein, two side ends of the cavity of the mold are respectively provided with a horn-shaped opening, and the two clamping portions are one For a conical part, when the metal pipe forming system performs a forming process, a metal round tube is placed in the cavity, the metal round tube in the mold is heated, and the two tapered clamps enter the heated part. The two ends of the metal round pipe are pressed against the two ends of the metal round pipe to the inner side wall of the horn-shaped opening of the cavity, so that the two ends of the metal round pipe are extruded into one respectively. Flared nozzle and makes the metal A sealed state is present between the horn-shaped nozzles at both ends of the tube and the two tapered clamps. A high-pressure gas is injected into the metal round pipe through the gas input hole, the gas pipeline, and the gas output hole. The pipe wall of the metal circular pipe is attached to the cavity to form a metal formed pipe with a special-shaped pipe diameter and a horn-shaped nozzle. The metal pipe fitting forming system according to item 1 of the patent application scope, wherein the inner surface of the cavity includes a patterned layer, and when the wall of the metal circular tube is impacted by the pressure of the high-pressure gas, the wall is attached to the cavity When the texture pattern layer is formed, the metal forming pipe having a profiled pipe diameter and a texture pattern is formed in the mold. The metal pipe fitting forming system according to item 1 of the scope of the patent application, wherein the metal round pipe is a metal round pipe with the same diameter, a tapered metal round pipe, or a metal round pipe with a different pipe diameter. The metal pipe forming system according to item 1 of the scope of patent application, wherein the upper mold and the lower mold each have a half cavity, and the half cavity of the upper mold and the half cavity of the lower mold are symmetrical or asymmetrical. Silhouette construction. The metal pipe fitting forming system according to item 1 of the patent application scope, wherein at least one heater is provided inside or around the mold, and when the metal pipe forming system executes the forming process, the heater will heat the mold. To a predetermined temperature, the predetermined temperature is 400 ~ 500 ° C. The metal pipe forming system according to item 1 of the scope of the patent application, wherein the metal round pipe is an aluminum magnesium alloy, a titanium alloy, or a pipe body of other metal materials. The metal pipe fitting forming system according to item 1 of the scope of patent application, wherein the pressure of the high-pressure gas is 50 to 200 kg / cm ² . The metal tube forming system according to item 1 of the patent application scope, wherein when the metal forming tube has been formed in the mold, the clamp portion of the clamp is withdrawn from the two mouths of the metal forming tube, and the mold is moved to A cooling platform. A metal pipe fitting forming system includes a mold including an upper mold and a lower mold. When the upper mold and the lower mold are closed, there is a cavity between the upper mold and the lower mold. The surface includes a texture pattern layer; and a pair of jigs, one side of each jig is provided with a clamping part, at least one of the jigs includes a gas input hole and a gas output hole, and the gas output hole is disposed on the clip part A gas pipeline is provided between the gas input hole and the gas output hole; wherein, the two sides of the cavity of the mold are respectively provided with a horn-shaped opening, and the two clamping portions are respectively a tapered member, When the metal pipe forming system executes a forming process, a metal round pipe is placed in the cavity, the metal round pipe in the mold is heated, and the two tapered clips enter the two of the heated metal round pipe. End nozzle to squeeze the two ends of the metal round pipe to the inner wall of the horn-shaped opening of the cavity, so that the two ends of the metal round pipe are extruded into a horn-shaped mouth And make the horn-shaped tube at both ends of the metal circular tube A sealed state is present between the two tapered clamping portions, and a high-pressure gas is injected into the metal round pipe through the gas input hole, the gas pipeline, and the gas output hole to make the wall of the metal round pipe. It is affixed to the texture pattern layer of the cavity to become a metal formed pipe with a texture pattern and a horn-shaped nozzle. According to the metal tube forming system according to item 9 of the scope of the patent application, wherein at least one heater is respectively provided around the mold. When the metal forming tube is formed to perform the forming process, the heater will heat the mold to one. The predetermined temperature is 400 to 500 ° C. The metal pipe fitting forming system according to item 9 of the scope of the patent application, wherein the metal round pipe is a pipe body of an aluminum-magnesium alloy, a titanium alloy, or other metal materials. The metal pipe fitting forming system according to item 9 of the scope of patent application, wherein the pressure of the high-pressure gas is 50 to 200 kg / cm ² . The metal pipe forming system according to item 9 of the scope of the patent application, wherein when the metal forming pipe has been formed in the mold, the clamp portion of the clamp exits from the nozzles on both sides of the metal round pipe, and the mold moves to A cooling platform. A method for forming a metal pipe fitting includes the steps of placing a metal round pipe in a cavity of a mold, wherein two sides of the cavity are respectively provided with horn-shaped openings; heating the mold to a preset temperature; The tapered clips of the pair of clamps are inserted into the two sides of the heated metal round pipe to clamp the metal round pipe; the tapered clips of the pair of clamps are used to squeeze the two sides of the metal round pipe to the The inner side wall of the horn-shaped opening of the cavity is extruded on both sides of the metal round pipe into a horn-shaped mouth and the two ends of the metal round pipe are formed with the horn-shaped mouth A clamped state is displayed between the clamps; and a high-pressure gas is injected into the metal round pipe through at least one of the clamps so that the wall of the metal round pipe is adhered to the inner surface of the cavity to become a Metal forming fittings with flared nozzles with irregular diameters or patterns. According to the method for forming a metal pipe fitting according to item 14 of the scope of the patent application, the method further includes a step of forming the metal forming pipe fitting on the mold and moving it to a cooling platform.