Pipe extrusion equipment and method

Abstract

The invention discloses pipe extrusion equipment and method, and the pipe extrusion equipment comprises an extrusion cylinder; the extrusion needle assembly comprises an extrusion needle and a needle tip installed at one end of the extrusion needle, a plurality of limiting parts are arranged on the periphery of the extrusion needle, and the limiting parts can abut against the end face of the extrusion cylinder; a mold assembly; the extrusion shaft is arranged on the periphery of the extrusion needle assembly in a sleeving mode and used for pushing the ingot blank to move towards the die assembly, a plurality of sliding grooves are formed in the periphery of the extrusion shaft, the limiting parts penetrate through the sliding grooves and can slide relative to the sliding grooves, and the number of the sliding grooves is not smaller than that of the limiting parts. According to the pipe extrusion equipment provided by the invention, the limiting part is arranged on the periphery of the extrusion needle, and under the cooperation of the sliding groove, the stress state of the structure, located at the rear end of the limiting part, in the extrusion needle assembly is effectively reduced, damage to the extrusion needle assembly and related parts is avoided, the reliability of the pipe extrusion equipment is improved, and the service life of the pipe extrusion equipment is prolonged.

Description

Technical Field

[0001] The invention relates to the field of pipe processing, and in particular to a pipe extrusion device and a method. Background Art

[0002] Heavy extruders above 5,000 tons usually use fixed needle or moving needle extrusion to produce seamless pipes, among which fixed needle extrusion is preferred.

[0003] At present, using a fixed needle to extrude pipes on an extruder with an independent perforation system can obtain excellent inner surface of the pipe, stable inner hole size of the pipe and efficient production capacity. However, due to the slippage of the metal relative to the extrusion needle when it is deformed and the large friction force generated on the surface of the extrusion needle, each part of the perforation system will be subjected to strong tensile force during the extrusion process. When the tensile force exceeds the maximum load that the weak part of the perforation system can bear, it will cause damage to the tool of the perforation system. Generally, the extrusion needle and the needle seat, and the needle seat and the connecting rod are connected by threads. Since the cross-sectional area of ​​the threaded connection part is significantly reduced, and the threaded part is prone to stress concentration, the overall maximum load bearing capacity of the tool is significantly reduced. Under the action of tension, fracture often occurs at the threaded connection between the extrusion needle and the needle seat, and the threaded connection between the needle seat and the connecting rod, causing tool accidents and leading to significant economic losses.

[0004] In the prior art, in order to enhance the maximum load bearing capacity of the perforation system, the size of the threaded part is increased as much as possible during the design and manufacture of the equipment. However, for a single device, due to space limitations, the thread size is severely limited, that is, the maximum load it can bear is significantly limited. For example, when the diameter of the extrusion needle of an 8,000-ton extruder reaches 300 mm, or when the extrusion needle of a 12,500-ton extruder reaches 360, the damage of its perforation system tool is at high risk. When the diameter of the extrusion needle of a 12,500-ton extruder reaches 420 mm or above, the risk of fracture in the production of high-strength alloy products is very large, and the fixed needle extrusion method is usually no longer selected. Therefore, when the aforementioned large-diameter or larger-diameter extrusion needle is used to extrude pipes, the follower needle extrusion method is often used. The tool specifications on the heavy extruder are large, and each damage to the tool will bring losses of tens of thousands to more than one million. Therefore, in the metal extrusion industries such as aluminum and aluminum alloys, magnesium and magnesium alloys, when large-diameter and ultra-large-diameter extrusion needles are used to produce pipes using the fixed needle extrusion method, it is difficult to avoid damage to the perforation system tools.

[0005] In addition, the maximum load that the perforation system can bear is significantly related to the size of the thread specifications. Since the perforation system is located on the center line of the extruder, it is restricted by space constraints and the matching constraints of tools such as the extrusion shaft, and the thread specifications are also limited. This results in the inability to arbitrarily increase the thread specifications in order to increase the maximum load capacity of the perforation system. Moreover, in the prior art, in order to avoid the excessive friction and tension acting on the needle tip and the extrusion needle during the extrusion process, which directly leads to damage to the perforation system tools, processing techniques that reduce the metal deformation resistance of the ingot as much as possible and measures such as using shorter ingots are also adopted. However, due to the large specifications of the ingots of heavy extruders, damage to the perforation system tools is still inevitable when producing large or extra-large pipes, which seriously limits the pipe production capacity of the equipment.

[0006] Therefore, how to effectively improve the bearing capacity of pipe extrusion equipment and improve production efficiency is a technical problem that technical personnel in this field currently need to solve. Summary of the invention

[0007] The object of the present invention is to provide a pipe extrusion device and method for improving the production efficiency of the pipe, reducing the cost, reducing the tension borne by the extrusion needle, and increasing the service life.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A pipe extrusion device, comprising:

[0010] An extrusion barrel, used for receiving the ingot;

[0011] An extrusion needle assembly can be inserted into or removed from the extrusion barrel, and the ingot is sleeved on the periphery of the extrusion needle assembly; the extrusion needle assembly comprises an extrusion needle and a needle tip installed at one end of the extrusion needle, and a plurality of limiting parts are arranged on the periphery of the extrusion needle, and the limiting parts can abut against the end surface of the extrusion barrel;

[0012] A die assembly is mounted at one end of the extrusion barrel, the needle tip can be inserted into a die hole of the die assembly, and a gap is provided between the needle tip and the die hole for forming the ingot;

[0013] An extrusion shaft is sleeved on the outer periphery of the extrusion needle assembly and is used to push the ingot to move in the direction of the mold assembly. In addition, a plurality of slide grooves are provided on the periphery of the extrusion shaft. The limiting portion passes through the slide grooves and can slide relative to the slide grooves. The number of the slide grooves is not less than the number of the limiting portions.

[0014] Preferably, a side of the limiting block close to the needle tip is a plane, and the plane of the limiting block can fit with the end surface of the extrusion cylinder.

[0015] Preferably, the limiting portion is block-shaped or plate-shaped, and an extending direction of the limiting portion is parallel to the axial direction of the extrusion needle.

[0016] Preferably, the limiting portion is in a right-angled trapezoid, and the right-angled side of the limiting portion is arranged close to the needle tip.

[0017] Preferably, it also includes an annular extrusion pad, which is located between the extrusion shaft and the ingot, and the extrusion shaft can push the ingot to move through the extrusion pad; and the inner diameter of the extrusion pad is 0.2-2mm larger than the outer diameter of the extrusion needle and 0.2-2.0mm smaller than the inner diameter of the extrusion barrel.

[0018] Preferably, the extrusion needle assembly also includes a needle seat and a connecting rod, the needle seat is located between the connecting rod and the extrusion needle, and the connecting rod and the needle seat, the needle seat and the extrusion needle, and the extrusion needle and the needle tip are all connected by internal threads and screws.

[0019] Preferably, the mold assembly comprises a mold sleeve and a mold and a mold pad which can be installed inside the mold sleeve, and the mold hole is located in the middle of the mold.

[0020] Preferably, the extrusion shaft is also provided with an axial hole, a front section and a rear section, the front section can enter the extrusion cylinder, and the axial hole is arranged on the axis of the extrusion shaft; the rear section is truncated cone-shaped, and the end with a smaller diameter is connected to the front section, the slide groove is opened on the front section, and each slide groove is arranged in parallel.

[0021] Preferably, the extrusion needle includes a needle front section, a needle screw and a needle internal thread, the needle screw and the needle internal thread are respectively located at the two ends of the extrusion needle, and the needle tip is connected to the needle front section; the limiting portion and the extrusion needle are an integrally formed structure, and each of the limiting portions is evenly distributed along the circumference of the extrusion needle; the number of the slide grooves and the limiting portions is the same, and they correspond one to one.

[0022] A pipe extrusion method, using the above-mentioned pipe extrusion equipment, comprises the following steps:

[0023] Putting the cylindrical ingot into the extrusion cylinder, and placing the die sleeve equipped with the die and the die pad against one end of the extrusion cylinder;

[0024] Controlling the extrusion needle to enter the extrusion barrel and pass through the ingot;

[0025] Controlling the needle tip to extend to the target position of the die hole of the die, and making the limiting part of the extrusion needle abut against the end surface of the extrusion cylinder;

[0026] The extrusion shaft is controlled to enter the extrusion cylinder and push the billet to start extrusion. The metal of the billet passes through the gap between the die hole and the needle tip to obtain a tube product.

[0027] The tube extrusion equipment provided by the present invention comprises: an extrusion barrel for accommodating an ingot; an extrusion needle assembly which can be inserted into or removed from the extrusion barrel, the ingot being sleeved on the periphery of the extrusion needle assembly; the extrusion needle assembly comprises an extrusion needle and a needle tip installed at one end of the extrusion needle, a plurality of limiting parts being provided on the periphery of the extrusion needle, the limiting parts being abutted against the end surface of the extrusion barrel; a mold assembly being installed at one end of the extrusion barrel, the needle tip being insertable into the mold hole of the mold assembly, a gap being provided between the needle tip and the mold hole for molding the ingot; an extrusion shaft being sleeved on the outer periphery of the extrusion needle assembly, for pushing the ingot to move in the direction of the mold assembly, and a plurality of sliding grooves being provided on the periphery of the extrusion shaft, the limiting parts passing through the sliding grooves, and the limiting parts being slidable relative to the sliding grooves, and the number of the sliding grooves being not less than the number of the limiting parts. The tube extrusion equipment provided by the present invention, by arranging the limiting portion on the periphery of the extrusion needle, and with the cooperation of the slide groove, when the extrusion shaft is pushed to move, the metal of the ingot will cover the needle tip and the extrusion needle, and when the metal of the ingot flows forward, it will generate a forward friction pulling force on the needle tip and the extrusion needle, and the friction pulling force will partially or completely act on the limiting portion, thereby effectively reducing the stress state of the structure at the rear end of the limiting portion in the extrusion needle assembly, avoiding damage to the extrusion needle assembly and related components, and improving the reliability and service life of the tube extrusion equipment.

[0028] The pipe extrusion method provided by the present invention adopts the pipe extrusion equipment as mentioned above, and includes the following steps: placing a cylindrical ingot into an extrusion barrel, and placing a die sleeve equipped with a die and a die pad against one end of the extrusion barrel; controlling an extrusion needle to enter the extrusion barrel and pass through the ingot; controlling the needle tip to extend to the target position of the die hole of the die, and making the limiting part of the extrusion needle abut against the end face of the extrusion barrel; controlling the extrusion shaft to enter the extrusion barrel and push the ingot to start extrusion, and the metal of the ingot passes through the gap between the die hole and the needle tip to obtain a pipe product. The tube extrusion method provided by the present invention adjusts the stress state of the extrusion needle by changing the structure of the extrusion needle, and makes the tensile force borne by the extrusion needle act on the extrusion barrel. Since the bearing capacity of the extrusion barrel is much higher than the bearing capacity of the extrusion needle assembly, the extrusion needle assembly and related components in the perforation system no longer form a through-type tensile force. Instead, the extrusion barrel is used as a carrier for the tensile force formed on the extrusion needle when the metal of the ingot is deformed, thereby fundamentally changing the stress state of the perforation system and avoiding damage to various tools in the perforation system, such as the extrusion needle, needle seat or connecting rod and other key tools. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 An exploded view of a specific embodiment of the tube extrusion equipment provided by the present invention;

[0031] Figure 2 for Figure 1 A cross-sectional view of the tube extrusion apparatus shown after assembly;

[0032] Figure 3 for Figure 1 A schematic diagram of the structure of an extrusion shaft in a tube extrusion device shown;

[0033] Figure 4 for Figure 1 A schematic diagram of the structure of an extrusion needle in a tube extrusion device shown;

[0034] Figure 5 A flow chart of the pipe extrusion method provided by the present invention;

[0035] Among them: 1 needle seat, 2 extrusion shaft, 21 shaft hole, 22 shaft rear section, 23 shaft front section, 24 slide groove, 3 extrusion needle, 31 needle screw, 32 limit part, 33 needle front section, 34 needle internal thread, 4 needle tip, 5 extrusion pad, 6 ingot, 7 extrusion cylinder, 8 die sleeve, 9 die, 10 die pad. DETAILED DESCRIPTION

[0036] The core of the present invention is to provide a pipe extrusion device and method, which can effectively improve the bearing capacity of the pipe extrusion device, reduce costs, and improve pipe production efficiency.

[0037] In order to enable those skilled in the art to better understand the solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0038] The pipe extrusion equipment and method provided by the present invention, under the premise of ensuring the fixed needle extrusion effect, significantly reduce or eliminate the tension transmitted from the ingot 6 to the thread of the extrusion needle assembly, so as to avoid damage to various components in the perforation system, significantly exert the equipment capacity, improve the pipe production efficiency, and reduce costs. Specifically, by setting a load-bearing limiter 32 on the extrusion needle 3, a slide groove 24 is correspondingly set on the extrusion shaft 2; the limiter 32 on the extrusion needle 3 can slide in the slide groove 24 to avoid interference with the extrusion shaft 2. The friction tension acting on the needle tip 4 and the extrusion needle 3 during the extrusion process is borne by the limiter 32 to the greatest extent, and no through-type tension is formed on the perforation system along the axial direction of the extrusion needle assembly, so that the force on the threaded connection of the perforation system is significantly reduced or not stressed; because the size of the limiter 32 is subject to small space constraints, it can adjust the size of its maximum load according to actual needs, and the range of selectable sizes is significantly increased.

[0039] Since the present invention significantly reduces or eliminates the tension at key connections such as the thread between the extrusion needle 3 and the needle seat 1 of the perforation system, and the thread between the needle seat 1 and the connecting rod, the maximum load that the perforation system can bear as a whole is more than three times that of the original perforation system. In actual production, unexpected damage to the perforation system tools is almost never expected.

[0040] Please refer to Figures 1 to 5 , Figure 1 An exploded view of a specific embodiment of the tube extrusion equipment provided by the present invention; Figure 2 for Figure 1 A cross-sectional view of the tube extrusion apparatus shown after assembly; Figure 3 for Figure 1 A schematic diagram of the structure of the extrusion shaft 2 in the pipe extrusion equipment shown; Figure 4 for Figure 1 A schematic diagram of the structure of the extrusion needle 3 in the tube extrusion device shown; Figure 5 The present invention is a flow chart of the tube extrusion method provided by the present invention.

[0041] In this embodiment, the tube extrusion apparatus comprises:

[0042] An extrusion barrel 7, used for accommodating the ingot 6;

[0043] The extrusion needle assembly can be inserted into or removed from the extrusion barrel 7, and the ingot 6 is sleeved on the periphery of the extrusion needle assembly; the extrusion needle assembly includes an extrusion needle 3 and a needle tip 4 installed at one end of the extrusion needle 3, and the periphery of the extrusion needle 3 is provided with a plurality of limiting portions 32, which can abut against the end surface of the extrusion barrel 7;

[0044] The die assembly is mounted at one end of the extrusion barrel 7, and the needle tip 4 can be inserted into the die hole of the die assembly. A gap is provided between the needle tip 4 and the die hole for forming the ingot 6;

[0045] The extrusion shaft 2 is sleeved on the outer periphery of the extrusion needle assembly, and is used to push the ingot 6 to move toward the mold assembly. In addition, a plurality of slide grooves 24 are provided on the periphery of the extrusion shaft 2. The limiting portion 32 passes through the slide groove 24, and the limiting portion 32 can slide relative to the slide groove 24. The number of the slide grooves 24 is not less than the number of the limiting portions 32.

[0046] It should be noted here that the setting position of the limit part 32 needs to be determined according to the processing requirements. When the limit part 32 abuts against the end face of the extrusion cylinder 7, the needle tip 4 should just move to the target position, that is, the gap size between the needle tip 4 and the die hole is just the size of the pipe to be processed.

[0047] Furthermore, it also includes an extrusion shaft 2 seat, on which the extrusion shaft 2 is installed. The extrusion shaft 2 is pushed to move by the extrusion shaft 2 seat to complete the extrusion forming of the ingot 6. For reasons that are easy for professionals to understand, the extrusion shaft 2 seat referred to in the present invention is not illustrated in the accompanying drawings.

[0048] To facilitate assembly, the slide groove 24 of the extrusion shaft 2 is open at the end of the extrusion shaft 2, so that when the extrusion shaft 2 is installed to the extrusion cylinder 7, the limiting portion 32 of the extrusion needle 3 can slide from the end of the slide groove 24 of the extrusion shaft 2 into the slide groove 24, which is convenient for assembly.

[0049] The hole in the middle of the extrusion barrel 7 is used to hold the ingot 6, and the ingot 6 is deformed in the extrusion barrel 7; the ingot 6 is a deformable metal, such as aluminum and aluminum alloy, magnesium and magnesium alloy, etc.; the ingot 6 is cylindrical, and its outer diameter is smaller than the inner diameter of the extrusion barrel 7, and the inner diameter of the ingot 6 is larger than the diameter of the extrusion needle 3. The length of the ingot 6 is shorter than the length of the extrusion barrel 7, and the specific length is not limited; the heated ingot 6 is placed in the extrusion barrel 7.

[0050] Specifically, the extrusion needle assembly is a part of the perforation system, and the perforation system is used to control the extrusion needle assembly to enter the extrusion barrel 7, and fix the extrusion needle assembly during the extrusion process to prevent the extrusion needle assembly from being out of position; the production process of seamless pipes with an independent perforation system is: the extrusion needle 3 is assembled with the needle seat 1 through a threaded connection, and the needle tip 4 is installed at the front end of the extrusion needle 3; the needle tip 4 has a sizing effect on the inner diameter of the pipe and determines the inner diameter size of the pipe; the billet 6 is placed in the circular hole of the extrusion barrel 7; the mold 9 is placed at one end of the extrusion barrel 7 and contacts the billet 6; the extrusion pad 5 is placed in the extrusion barrel 7; the extrusion pad 5 and the mold 9 They are respectively located at the two ends of the ingot 6; the extrusion needle 3 equipped with the needle tip 4 passes through the hole of the extrusion pad 5 and the hole of the ingot 6, so that the front working part of the needle tip 4 extends into the hole of the die hole and keeps the limit to ensure that the extrusion needle 3 will not move beyond expectations during the extrusion process; the extrusion shaft 2 pushes the extrusion pad 5 to extrude the ingot 6, and the ingot 6 produces plastic deformation under high temperature and high pressure, and the metal flows out from the gap between the die hole and the needle tip 4 to form the required product; during the extrusion process, the metal of the ingot 6 will cover the needle tip 4 and the extrusion needle 3, and when the metal flows forward, it will produce a forward friction pulling force on the needle tip 4 and the extrusion needle 3.

[0051] The method of the present invention to prevent the perforation system tool from breaking is:

[0052] When the metal of the billet 6 is deformed, frictional pulling force is generated on the needle tip 4 and the extrusion needle 3. The extrusion needle 3 is pulled forward, and the limiting portion 32 on the extrusion needle 3 is pressed against the end face of the extrusion cylinder 7. The end face of the extrusion cylinder 7 forms a support for the limiting portion 32. The force exerted by the end face of the extrusion cylinder 7 on the limiting portion 32 is approximately equal to the frictional pulling force generated by the metal of the billet 6 on the needle tip 4 and the extrusion needle 3 when it is deformed, and the directions of the two forces are opposite. At this time, the section of the extrusion needle 3 from the limiting portion 32 to the needle seat 1 does not bear the tension, including the external thread at the connection between the needle seat 1 and the extrusion needle 3 and the dangerous section at the internal thread. These dangerous sections are no longer prone to breakage.

[0053] The tube extrusion equipment provided by the present invention has a limiting portion 32 arranged on the periphery of the extrusion needle 3, and with the cooperation of the slide groove 24, when the extrusion shaft 2 is pushed to move, the metal of the ingot 6 will cover the needle tip 4 and the extrusion needle 3, and when the metal of the ingot 6 flows forward, it will generate a forward frictional pulling force on the needle tip 4 and the extrusion needle 3, and the frictional pulling force will partially or completely act on the limiting portion 32, thereby effectively reducing the stress state of the structure at the rear end of the limiting portion 32 in the extrusion needle assembly, avoiding damage to the extrusion needle assembly and related components, and improving the reliability and service life of the tube extrusion equipment.

[0054] In some embodiments, the side of the stopper block close to the needle tip 4 is a plane, and the plane of the stopper block can fit with the end face of the extrusion cylinder 7. Specifically, by setting a plane on the stopper block, the stability of the stopper block when it abuts against the end face of the extrusion cylinder 7 can be ensured, so that the tension borne by the extrusion needle 3 is better transmitted to the extrusion cylinder 7, while avoiding reducing the influence of the stopper block on the end face of the extrusion cylinder 7. Of course, under conditional operation, the side of the stopper block close to the needle tip 4 can also be a concave-convex surface or a curved surface.

[0055] In some embodiments, the limiting portion 32 is block-shaped or plate-shaped, and the extension direction of the limiting portion 32 is parallel to the axial direction of the extrusion needle 3. Specifically, when the limiting portion 32 is block-shaped, the connection part between the limiting portion 32 and the extrusion needle 3 has a larger area and higher strength; the limiting portion 32 is preferably plate-shaped, and the plane where the limiting portion 32 is located is parallel to the axial direction of the extrusion needle 3, that is, the connection part between the limiting portion 32 and the extrusion needle 3 is strip-shaped, and the strip-shaped connection part is parallel to the axial direction of the extrusion needle 3. This is set to reduce the width of the slide 24, which can not only ensure the strength of the limiting portion 32, but also reduce the influence of the slide 24 on the strength of the extrusion shaft 2. That is, under the premise of ensuring that the limiting portion 32 and the slide 24 are matched, the width of the slide 24 should be as small as possible to reduce the influence on the extrusion shaft 2.

[0056] In some embodiments, the limiting portion 32 is in a right-angled trapezoid, and the right-angled side of the limiting portion 32 is arranged close to the needle tip 4. Specifically, in the right-angled trapezoid structure, on the one hand, the right-angled side of the limiting portion 32, that is, the side of the limiting portion 32 close to the needle tip 4 is a plane, which is fitted and abutted with the extrusion cylinder 7; on the other hand, the hypotenuse of the limiting portion 32, that is, the side of the limiting portion 32 away from the needle tip 4 is an inclined surface, which can increase the area of ​​the connection structure between the limiting portion 32 and the extrusion needle 3, thereby improving the stability of the limiting portion 32. Furthermore, the limiting portion 32 is preferably a right-angled trapezoidal plate-like structure, which is convenient for cooperation with the slide groove 24 and reduces the impact on the width of the slide groove 24.

[0057] In some embodiments, an annular extrusion pad 5 is also included, and the extrusion pad 5 is located between the extrusion shaft 2 and the billet 6. The extrusion shaft 2 can push the billet 6 to move through the extrusion pad 5. Specifically, one end of the billet 6 contacts the extrusion pad 5, and the other end contacts the mold 9; the extrusion cylinder 7, the extrusion needle 3, the extrusion pad 5, the mold sleeve 8, the mold 9 and the needle tip 4 form an incompletely enclosed space, and the billet 6 is placed in the incompletely enclosed space. There is only a gap between the needle tip 4 and the mold 9 in the incompletely enclosed space, and the gap is used for the metal of the billet 6 to flow out from it to form a tube. During operation, the extrusion pad 5 moves toward the mold 9 under the push of the extrusion shaft 2 to form an extrusion of the billet 6. The metal of the billet 6 undergoes plastic deformation under high temperature and high pressure, and flows out from the gap between the needle tip 4 and the mold 9, forming an extruded tube product with an outer shape similar to the size of the mold 9 cavity and an inner cavity shape similar to the cross-sectional shape of the needle tip 4. Preferably, the extrusion pad 5 is a round cake with holes, which is located between the ingot 6 and the extrusion shaft 2 when in use. Its function is to seal the metal of the ingot 6 to prevent the metal of the ingot 6 from overflowing toward the extrusion shaft 2.

[0058] Preferably, the outer diameter of the extrusion pad 5 is 0.2-2.0 mm smaller than the inner diameter of the extrusion cylinder 7, and the inner diameter of the extrusion pad 5 is 0.2-2.0 mm larger than the diameter of the extrusion needle 3. The thickness of the extrusion pad 5 is not limited. In other words, the gap between the extrusion pad 5 and the extrusion cylinder 7 and the extrusion needle 3 is sufficient to ensure relative movement, and the gap should be reduced as much as possible to avoid metal overflow from the ingot 6.

[0059] In some embodiments, the extrusion needle assembly further includes a needle seat 1 and a connecting rod, the needle seat 1 is located between the connecting rod and the extrusion needle 3, and the connecting rod and the needle seat 1, the needle seat 1 and the extrusion needle 3, and the extrusion needle 3 and the needle tip 4 are all connected by internal threads and screws, and the screw is provided with external threads. Specifically, the needle tip 4 is used to sizing the inner diameter of the tube, which determines the size of the tube cavity; the cross-section of the working part of the needle tip 4 can be circular or non-circular; the needle tip 4 is provided with a screw, and the external thread of the screw is connected to the internal thread 34 of the extrusion needle 3. Similarly, the needle seat 1 is provided with a screw, and the external thread of the screw is connected to the internal thread of the connecting rod. Further, the needle seat 1 is used to connect the extrusion needle 3 and the connecting rod. For reasons that are easy for professionals to understand, the connecting rod referred to in the present invention is not shown in the drawings of the specification; the needle seat 1 is provided with an internal thread at one end close to the extrusion needle 3, and the internal thread and the external thread on the needle screw 31 of the extrusion needle 3 form a thread pair. The needle seat 1 is provided with an external thread near one end of the connecting rod, and the external thread and the internal thread of the connecting rod form a thread pair.

[0060] In some embodiments, the mold assembly includes a mold sleeve 8 and a mold 9 and a mold cushion 10 that can be installed inside the mold sleeve 8, and the mold hole is located in the middle of the mold 9. Specifically, the mold 9 is used for metal forming, and is provided with a mold cavity, and the mold cavity is provided with a working belt, and the working belt plays a sizing role on the outer diameter of the pipe and determines the outer size of the pipe; the mold cushion 10 is used to support the mold 9 to enhance the rigidity of the mold 9; the mold cavity of the mold cushion 10 is a through hole, and the cross section of the through hole is similar to and larger than the cross section of the mold cavity outlet of the mold 9; the mold sleeve 8 is used to assemble the mold 9 and the mold cushion 10 to constrain the radial positions of the mold 9 and the mold cushion 10; the mold sleeve 8 is located at one end of the ingot 6.

[0061] In some embodiments, the extrusion shaft 2 is further provided with an axial hole 21, a shaft front section 23 and a shaft rear section 22. The shaft front section 23 can enter the extrusion barrel 7, and the axial hole 21 is arranged on the axis of the extrusion shaft 2; the shaft rear section 22 is truncated cone-shaped, and the end with a smaller diameter is connected to the shaft front section 23, and a slide groove 24 is provided on the shaft front section 23, and each slide groove 24 is arranged in parallel. Specifically, the extrusion shaft 2 is provided with an axial hole 21, a shaft rear section 22, a shaft front section 23 and a slide groove 24; the axial hole 21 of the extrusion shaft 2 is a central through hole along the axial direction; the diameter of the axial hole 21 is larger than the maximum diameter of the needle front section 33 of the extrusion needle 3, and is larger than the maximum diameter of the section of the needle seat 1 that needs to enter the axial hole 21, so as to ensure the passability of the needle seat 1 and the extrusion needle 3 in the axial hole 21; the maximum outer diameter of the shaft rear section 22 is larger than the outer diameter of the shaft front section 23; the shaft rear section 22 cooperates with other tools and has an assembly function; the shaft of the extrusion shaft 2 The front section 23 has a uniform cross-section or a non-uniform cross-section, preferably a uniform cross-section; a slide groove 24 is provided axially on the front section 23 of the shaft, and the slide groove 24 passes through the center of the shaft outward in the radial direction of the extrusion shaft 2, and the slide groove 24 extends axially to the end face of the front section 23 of the shaft and passes through the end face of the front section 23 of the shaft; no slide groove 24 is provided at the rear section 22 of the shaft to ensure the strength and stability of the rear section 22 of the shaft; the width of the slide groove 24 is greater than the thickness of the limiting portion 32 of the extrusion needle 3; the number of the slide grooves 24 is the same as the number of the limiting portions 32 of the extrusion shaft 2.

[0062] In some embodiments, the extrusion needle 3 includes a needle front section 33, a needle screw 31 and a needle internal thread 34, the needle screw 31 and the needle internal thread 34 are respectively located at the two ends of the extrusion needle 3, and the needle tip 4 is connected to the needle front section 33; the limiting portion 32 and the extrusion needle 3 are an integrally formed structure, and each limiting portion 32 is evenly distributed along the circumference of the extrusion needle 3; the number of the slide grooves 24 and the limiting portions 32 is the same, and they correspond one to one. Specifically, the extrusion needle 3 is provided with a needle internal thread 34, a needle front section 33, a limiting portion 32 and a needle screw 31, the limiting portions 32 are distributed around the extrusion needle 3, and extend radially outward of the extrusion needle 3 to form a claw structure; the limiting portion 32 of the extrusion needle 3 cooperates with the slide groove 24 of the extrusion shaft 2, and the limiting portion 32 can slide in the slide groove 24. During extrusion, the limiting portion 32 of the extrusion needle 3 is in contact with the end face of the extrusion cylinder 7, and the friction tension generated when the metal of the ingot 6 is deformed can act on the end face of the extrusion cylinder 7 partially or completely through the limiting portion 32. The number of limiting portions 32 of the extrusion needle 3 can be set to 2-8, preferably 2-4. The shape of the limiting portion 32 of the extrusion needle 3 is not limited, and can be rectangular, triangular, etc. The thickness of the limiting portion 32 is not limited. The needle screw 31 of the extrusion needle 3 cooperates with the internal thread of the needle seat 1 to form a thread pair. The needle front section 33 of the extrusion needle 3 is a working section, and its diameter is smaller than the inner hole diameter of the extrusion pad 5 and the inner hole diameter of the ingot 6, and is 0.2-2mm smaller than the inner hole diameter of the extrusion pad 5.

[0063] The tube extrusion equipment fundamentally changes the stress state of the perforation system by transferring the frictional tension acting on the extrusion needle 3 to the end face of the extrusion cylinder 7 through the limiter 32 on the extrusion needle 3; the extrusion cylinder 7 can withstand a large force, so the limiter 32 is flexibly designed and the size of the force it can withstand can be determined according to needs; the maximum load-bearing capacity of the perforation system can be significantly improved, and the tube production capacity limit of the original design of the equipment can be significantly improved and exceeded.

[0064] In addition to the above-mentioned pipe extrusion equipment, the present invention also provides a pipe extrusion method.

[0065] The pipe extrusion method comprises the following steps:

[0066] Step S1: placing a cylindrical ingot 6 into an extrusion barrel 7, and placing a die sleeve 8 equipped with a die 9 and a die cushion 10 against one end of the extrusion barrel 7;

[0067] Step S2: Control the extrusion needle 3 to enter the extrusion barrel 7 and pass through the ingot 6;

[0068] Step S3: Control the needle tip 4 to extend to the target position of the die hole of the die 9, and make the limiting portion 32 of the extrusion needle 3 abut against the end surface of the extrusion cylinder 7;

[0069] Step S4: Control the extrusion shaft 2 to enter the extrusion barrel 7 and push the ingot 6 to start extrusion. The metal of the ingot 6 passes through the gap between the die hole and the needle tip 4 to obtain a tube product.

[0070] In some embodiments, before the step of controlling the extrusion needle 3 to enter the extrusion cylinder 7, the step further includes:

[0071] Install the extrusion pad 5 into the extrusion cylinder 7 from the other end of the extrusion cylinder 7;

[0072] The step of controlling the extrusion needle 3 to enter the extrusion cylinder 7 and pass through the ingot 6 also includes: controlling the extrusion needle 3 to enter the extrusion cylinder 7 and pass through the extrusion pad 5 and the ingot 6.

[0073] In a specific embodiment, the tube extrusion method comprises the following steps:

[0074] Connect and assemble the needle seat 1 and the connecting rod;

[0075] Assemble and fix the extrusion shaft 2 and the extrusion shaft 2 seat;

[0076] The needle seat 1 is inserted into the extrusion shaft 2 as far as possible from the shaft hole 21 of the rear section 22 of the extrusion shaft 2;

[0077] The end of the needle screw 31 of the extrusion needle 3 passes through the extrusion shaft 2 from the shaft hole 21 of the shaft front section 23 of the extrusion shaft 2, and keeps the limiting part 32 outside the slide groove 24, and screws the extrusion needle 3 to assemble and fix it with the needle seat 1;

[0078] Operate the rotating mechanism of the perforating system to adjust the position of the limiting part 32, so that the limiting part 32 is aligned with the slide groove 24 of the extrusion shaft 2, and ensure that the limiting part 32 can slide freely in the slide groove 24; it should be noted that: when the limiting part 32 of the extrusion needle 3 is located outside the slide groove 24 of the extrusion shaft 2 and the extrusion needle 3 cannot be screwed and tightened, the limiting part 32 of the extrusion needle 3 should enter the slide groove 24 of the extrusion shaft 2, and keep the extrusion shaft 2 and the extrusion shaft 2 seat loose, and screw the extrusion shaft 2 and the extrusion needle 3 at the same time, ensure that the extrusion needle 3 and the needle seat 1 are screwed firmly, and then assemble and fix the extrusion shaft 2 and the extrusion shaft 2 seat;

[0079] The needle tip 4 is screwed and fixed on the extrusion needle 3; the needle screw 31 on the needle tip 4 and the inner thread 34 of the extrusion needle 3 form a thread pair;

[0080] The extrusion shaft 2 is pushed to start the molding process, and the limiting portion 32 is kept in contact with the extrusion cylinder 7 until the molding is completed, and the extrusion needle assembly is taken out.

[0081] The pipe extrusion equipment and method provided by the present invention have the following advantages:

[0082] 1. A limiting portion 32 is provided on the extrusion needle 3 of the present invention, and the frictional pulling force acting on the extrusion needle 3 during the extrusion process is transmitted to the extrusion cylinder 7 through the limiting portion 32, thereby reducing or eliminating the pulling force at the external thread of the needle screw 31 of the extrusion needle 3, the internal thread of the needle seat 1, and the external thread of the needle seat 1, thereby avoiding damage to the extrusion needle 3 and the needle seat 1.

[0083] 2. The extrusion shaft 2 of the present invention is provided with a slide groove 24 , and the limiting portion 32 of the extrusion needle 3 can slide in the slide groove 24 , thereby avoiding interference between the extrusion needle 3 and the extrusion shaft 2 .

[0084] 3. The implementation of the present invention can completely solve the risk of breakage of the extrusion needle 3 and the needle seat 1 of the heavy-duty extruder, and can significantly improve the ultimate capacity of the equipment for pipe production.

[0085] 4. By adopting the perforation system related tools and pipe production process of the present invention, the fixed needle extrusion method is used to produce pipes, which can significantly improve the maximum load-bearing capacity of the perforation system and significantly improve and break through the pipe production capacity limit of the original design of the equipment.

[0086] The tube extrusion method provided by the present invention adjusts the stress state of the extrusion needle 3 by changing the structure of the extrusion needle 3, and applies the tensile force borne by the extrusion needle 3 to the extrusion barrel 7. Since the bearing capacity of the extrusion barrel 7 is much higher than the bearing capacity of the extrusion needle assembly, the extrusion needle assembly and related components in the perforation system no longer form a through-type tensile force. Instead, the extrusion barrel 7 is used as a carrier of the tensile force formed on the extrusion needle 3 when the metal of the ingot 6 is deformed, thereby fundamentally changing the stress state of the perforation system and avoiding damage to various tools in the perforation system, such as the extrusion needle 3, the needle seat 1 or the connecting rod and other key tools.

[0087] The above is a detailed introduction to the pipe extrusion equipment and method provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core ideas of the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A pipe extrusion device, characterized in that, it includes: an extrusion cylinder (7) for accommodating an ingot blank (6); an extrusion needle assembly that can extend into or move out of the extrusion cylinder (7), and the ingot blank (6) is sleeved on the periphery of the extrusion needle assembly; the extrusion needle assembly includes an extrusion needle (3) and a needle tip (4) installed at one end of the extrusion needle (3), and a plurality of limiting parts (32) are arranged on the periphery of the extrusion needle (3), and the limiting parts (32) can abut against the end face of the extrusion cylinder (7); a die assembly installed at one end of the extrusion cylinder (7), the needle tip (4) can be inserted into the die hole of the die assembly, and a gap for forming the ingot blank (6) is provided between the needle tip (4) and the die hole; an extrusion shaft (2) sleeved on the outer periphery of the extrusion needle assembly for pushing the ingot blank (6) to move towards the die assembly, and a plurality of sliding grooves (24) are arranged on the periphery of the extrusion shaft (2), the limiting parts (32) penetrate through the sliding grooves (24), and the limiting parts (32) can slide relative to the sliding grooves (24), and the number of the sliding grooves (24) is not less than the number of the limiting parts (32).

2. The pipe extrusion device according to claim 1, characterized in that, one side of the limiting block close to the needle tip (4) is a plane, and the plane of the limiting block can be attached to the end face of the extrusion cylinder (7).

3. The pipe extrusion device according to claim 2, characterized in that, the limiting part (32) is in a block shape or a plate shape, and the extending direction of the limiting part (32) is parallel to the axial direction of the extrusion needle (3).

4. The pipe extrusion device according to claim 3, characterized in that, the limiting part (32) is in a right trapezoid shape, and the right-angled side of the limiting part (32) is arranged close to the needle tip (4).

5. The pipe extrusion device according to claim 1, characterized in that, it further includes an annular extrusion pad (5), the extrusion pad (5) is located between the extrusion shaft (2) and the ingot blank (6), and the extrusion shaft (2) can push the ingot blank (6) to move through the extrusion pad (5); and the inner diameter of the extrusion pad (5) is 0.2 - 2 mm larger than the outer diameter of the extrusion needle (3) and 0.2 - 2.0 mm smaller than the inner diameter of the extrusion cylinder (7).

6. The pipe extrusion device according to claim 1, characterized in that, the extrusion needle assembly further includes a needle base (1) and a connecting rod, the needle base (1) is located between the connecting rod and the extrusion needle (3), and between the connecting rod and the needle base (1), between the needle base (1) and the extrusion needle (3), and between the extrusion needle (3) and the needle tip (4), internal threads and screws are used for connection.

7. The pipe extrusion device according to claim 1, characterized in that, the die assembly includes a die sleeve (8) and a die (9) and a die pad (10) that can be installed inside the die sleeve (8), and the die hole is located in the middle of the die (9).

8. The pipe extrusion device according to any one of claims 1 to 7, It is characterized in that an axle hole (21), a front axle section (23) and a rear axle section (22) are further arranged on the extrusion shaft (2), the front axle section (23) can enter the extrusion barrel (7), and the axle hole (21) runs through the axis of the extrusion shaft (2); the rear axle section (22) is in a frustum shape, and the end with a smaller diameter is connected to the front axle section (23), the sliding grooves (24) are arranged on the front axle section (23), and the sliding grooves (24) are arranged in parallel.

9. The pipe extrusion equipment according to claim 8, It is characterized in that the extrusion needle (3) comprises a front needle section (33), a needle screw (31) and an internal needle thread (34), the needle screw (31) and the internal needle thread (34) are respectively located at two ends of the extrusion needle (3), and the needle tip (4) is connected to the front needle section (33); the limiting part (32) and the extrusion needle (3) are of an integrally formed structure, and the limiting parts (32) are evenly distributed along the circumferential direction of the extrusion needle (3); the number of the sliding grooves (24) is the same as that of the limiting parts (32) and they correspond to each other one by one.

10. A pipe extrusion method, using the pipe extrusion equipment according to any one of claims 1 to 9, It is characterized in that it comprises the following steps: Put the cylindrical billet (6) into the extrusion barrel (7), and make the die sleeve (8) equipped with the die (9) and the die cushion (10) abut against one end of the extrusion barrel (7); Control the extrusion needle (3) to enter the extrusion barrel (7) and pass through the billet (6); Control the needle tip (4) to extend into the target position of the die hole of the die (9), and make the limiting part (32) of the extrusion needle (3) abut against the end face of the extrusion barrel (7); Control the extrusion shaft (2) to enter the extrusion barrel (7), and push the billet (6) to start extrusion, and the metal of the billet (6) passes through the gap between the die hole and the needle tip (4) to obtain a pipe product.

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