Preparation method of composite pipe for vibration and noise reduction

Abstract

The invention discloses a preparation method of a composite pipe for vibration and noise reduction, and relates to the technical field of metal material preparation, in order to solve the problems that an existing prepared composite pipe is poor in pressure resistance and vibration reduction and sound absorption capacities, the preparation method comprises the steps that an inner layer metal pipe, an outer layer metal pipe and foaming powder are integrally extruded and formed, and a pipe blank composite pipe blank is obtained; the pipe blank composite pipe blank is heated, rolling forming is conducted on the pipe blank composite pipe blank, the temperature of a contact interface between the structures of the pipe blank composite pipe blank is increased to a preset temperature, a metallurgical bonding target bonding interface is formed on the contact interface, and a target composite pipe blank is obtained; and the target composite pipe blank is placed in a heating furnace, the middle layer of the target composite pipe blank is foamed to form a foam metal layer, and the foam metal sandwich composite pipe is obtained. The preparation method provided by the invention is used for improving the compressive strength and the vibration reduction and sound absorption performance of the foam metal sandwich composite pipe.

Description

Technical Field

[0001] The invention relates to the technical field of metal material preparation, and in particular to a method for preparing a composite pipe for vibration reduction and noise reduction. Background Art

[0002] Composite pipes are the main material for preparing deep-sea hydraulic actuator housings, which are key equipment used in deep-sea engineering and ocean exploration. The composite pipes used in existing hydraulic actuator housings are usually bimetallic composite pipes, which are new metal materials formed by combining two different component metals through an interface. They combine the advantages of different materials and can achieve unique properties such as light weight, high compressive strength, corrosion resistance, fatigue resistance, and impact resistance. However, due to their inherent high density, high rigidity, and strong physical properties, bimetallic composite pipes make sound waves more likely to be reflected rather than effectively absorbed when they contact the surface of the material, which is particularly difficult to absorb for high-frequency sound waves. At the same time, the multi-layer interface inside the composite structure may cause complex reflection and refraction of sound waves, further weakening its sound absorption efficiency, resulting in poor sound absorption performance of the hydraulic actuator housing.

[0003] Although the existing foam metal composite tube has good sound absorption and vibration reduction functions, the existing method of preparing the foam metal composite tube cannot achieve the metallurgical bonding of the foam metal and the base metal, resulting in poor compressive resistance of the foam metal composite tube, which cannot meet the requirements of high compressive strength and effective vibration reduction and sound absorption of the hydraulic actuator housing. Summary of the invention

[0004] The object of the present invention is to provide a method for preparing a composite pipe for vibration reduction and noise reduction, so as to improve the compressive strength and vibration reduction and sound absorption performance of the foam metal sandwich composite pipe.

[0005] The present invention provides a method for preparing a composite pipe for vibration reduction and noise reduction, comprising: Provide inner metal tube, outer metal tube and foaming powder; The inner metal tube, the outer metal tube and the foaming powder are extruded into a single body to obtain a composite tube blank; The tube blank composite tube blank is heated to a target temperature, and the tube blank composite tube blank is rolled into shape by a three-roller inclined rolling mill, so that the temperature of the contact interface between the structures of the tube blank composite tube blank is increased to a preset temperature during the forming process, and the preset temperature is greater than or equal to the melting point temperature of the foaming powder, and the contact interface forms a target bonding interface of metallurgical bonding to obtain a target composite tube blank; the target temperature is less than the melting point temperature; The target composite tube blank is placed in a heating furnace to foam the middle layer of the target composite tube blank to form a foam metal layer, thereby obtaining a foam metal sandwich composite tube.

[0006] Optionally, the step of integrally extruding the inner metal tube, the outer metal tube and the foaming powder to obtain a composite tube blank comprises: The inner metal tube and the outer metal tube are placed in a cavity formed by a tube blank forming outer die and a tube blank forming inner die, and the foaming powder is poured into the gap between the inner metal tube and the outer metal tube; the inner metal tube is placed on a side close to the tube blank forming inner die, and the outer metal tube is placed on a side close to the tube blank forming outer die; The oscillating base of the tube blank set mold is started, and the foaming powder is compacted into an annular prefabricated foam blank by using an annular pressing head during the oscillation process of the oscillating base to obtain a tube blank composite tube blank.

[0007] Optionally, the target composite tube billet is prepared by a rolling tool, which includes: a three-roll oblique rolling mill and a mandrel, wherein a first induction heating coil is arranged in the mandrel, a second induction heating coil is fixed at the rolling mill entrance of the three-roll oblique rolling mill, the mandrel passes through the second induction heating coil and the oblique rolling hole of the three-roll oblique rolling mill, and the second induction heating coil is sleeved on one end of the mandrel provided with the first induction heating coil.

[0008] Optionally, the target temperature includes a first target temperature and a second target temperature; the step of heating the tube blank composite tube blank to the target temperature and rolling the tube blank composite tube blank through a three-roller inclined rolling mill so that the temperature of the contact interface between the structures of the tube blank composite tube blank is increased to a preset temperature during the forming process, the preset temperature is greater than or equal to the melting point temperature of the foaming powder, and the contact interface forms a target bonding interface of metallurgical bonding, and obtaining the target composite tube blank includes: Sleeving the tube blank composite tube onto the mandrel, and placing the tube blank composite tube between the first induction heating coil and the second induction heating coil; Starting the first induction heating coil to heat the temperature of the inner metal tube to a first target temperature; starting the second induction heating coil to heat the outer metal tube to a second target temperature; Using a mandrel trolley to drive the mandrel to move along the axial direction of the mandrel, so that the mandrel and the tube blank composite tube blank enter the oblique rolling hole; The rollers of the three-roller oblique rolling mill are used to reduce the diameter and wall of the composite tube billet in the radial direction; the contact interface between the various structures of the composite tube billet is heated to a preset temperature under the action of rolling; the preset temperature is greater than or equal to the melting point of the foaming powder, so that the contact interface is remelted to form a target bonding interface for metallurgical bonding, thereby obtaining a target composite tube billet.

[0009] Optionally, before heating the tube blank composite tube blank to the target temperature, the method further comprises: According to the formula: ; Calculating and obtaining the target temperature; in, is the target temperature, is the melting point of the foaming powder, is the specific heat capacity of the inner metal tube or the specific heat capacity of the outer metal tube, is the density of the inner metal tube or the density of the outer metal tube, is the deformation amount of the composite tube billet.

[0010] Optionally, the tube blank set mold includes: a tube blank forming inner mold, a tube blank forming outer mold, an annular pressure head and an oscillation base; the tube blank forming inner mold is a cylindrical structure, the tube blank forming outer mold is sleeved on the outer surface of the tube blank forming inner mold, a cavity is formed between the tube blank forming inner mold and the tube blank forming outer mold, and the lower surface of the tube blank forming inner mold and the lower surface of the tube blank forming outer mold are connected to the upper surface of the oscillation base.

[0011] Optionally, the foam metal sandwich composite tube includes an inner metal tube, a foam metal layer and an outer metal tube from the inside to the outside; the target bonding interface between the inner metal tube, the foam metal layer and the outer metal tube is a metallurgical bonding interface.

[0012] Compared with the prior art, the present invention provides a composite tube preparation method for vibration reduction and noise reduction by providing an inner metal tube, an outer metal tube and a foaming powder; the inner metal tube, the outer metal tube and the foaming powder are extruded and formed as a whole, so that the preparation of the annular prefabricated foamed blank and the sheathing assembly are carried out simultaneously, and the sheathing assembly efficiency is improved. The various structures of the obtained tube blank composite tube blank are tightly combined, and the phenomenon that the gap sheathing causes the different layers of tube blanks to shift during the subsequent rolling and compounding process, resulting in the failure of the combination; the tube blank composite tube blank is heated to the target temperature, and the tube blank composite tube blank is rolled and formed by a three-roller oblique rolling mill, so that the temperature of the contact interface between the various structures of the tube blank composite tube blank is increased during the forming process. During the rolling process, the temperature is raised to a preset temperature, which is greater than or equal to the melting point temperature of the foaming powder, and the contact interface forms a metallurgical bonding target bonding interface to obtain a target composite tube blank; since the temperature of the contact interface is the preset temperature reached by the deformation heat, the temperature rise will not be particularly large, and the temperature of the contact interface can reach the melting point temperature but not reach the foaming temperature of the middle layer of the tube blank composite tube blank. The middle layer of the tube blank composite tube blank will not foam during the rolling and compounding process, so the various structures of the tube blank composite tube blank are more tightly combined under the action of rolling; then the target composite tube blank is placed in a heating furnace to foam the middle layer of the target composite tube blank, thereby obtaining a foam metal sandwich composite tube. The foam metal sandwich composite tube material prepared by this method has high strength, high stability, high corrosion resistance, and excellent sound absorption and vibration reduction performance. The hydraulic actuator shell prepared based on this material not only has light weight, high strength and excellent sound absorption and vibration reduction performance, but also can maintain excellent performance in extreme environments such as deep sea high pressure, low temperature, and high salt, thereby meeting the urgent demand for high-performance functional shell materials for deep-sea hydraulic actuators. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 A flow chart of a composite pipe preparation method for vibration and noise reduction provided by the present invention; Figure 2 A schematic diagram of the process of forming a composite tube blank provided by the present invention; Figure 3 A schematic diagram of the structure of a tube blank composite tube blank provided by the present invention; Figure 4 A schematic diagram of the rolling forming of the target composite tube provided by the present invention; Figure 5 A cross-sectional view of the induction heating coil provided by the present invention; Figure 6 This is a schematic structural diagram of the foam metal sandwich composite tube provided by the present invention.

[0014] Reference numerals: 1-tube blank composite tube blank, 11-inner metal tube, 12-outer metal tube, 13-annular prefabricated foam blank, 21-tube blank forming inner mold, 22-tube blank forming outer mold, 23-oscillation base, 24 annular pressure head, 41-mandrel, 42-three-roller oblique rolling mill, 43-second induction heating coil, 411-first induction heating coil. DETAILED DESCRIPTION

[0015] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0016] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0017] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The meaning of "several" is one or more, unless otherwise clearly and specifically defined.

[0018] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by the terms "up", "down", "front", "back", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0019] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] With the increasing depletion of onshore and coastal resources, the world's marine powers have shifted their development focus from offshore to deep-sea areas. The rapid progress of deep-sea equipment has made it possible to develop and utilize deep-sea resources on a large scale. However, the extreme environment of the deep sea, such as high pressure, low temperature, and high salt, poses severe challenges to the shell design of marine equipment. Composite pipes are one of the main materials for preparing hydraulic actuator shells. However, the existing composite pipes are mainly double-gold composite pipes and foam metal composite pipes. However, while double-gold composite pipes have compressive strength and corrosion resistance, they have weak vibration and sound absorption. Although foam metal composite pipes have good vibration and sound absorption capabilities, they have poor compressive and corrosion resistance.

[0021] In order to solve the above problems, the present invention provides a method for preparing a composite pipe for vibration reduction and noise reduction, which will be described below with reference to the accompanying drawings.

[0022] See also Figure 1 The present invention provides a method for preparing a composite pipe for vibration reduction and noise reduction, comprising the following steps: Step S1: providing an inner metal tube, an outer metal tube and foaming powder; The inner metal tube and the outer metal tube are two different high-strength and corrosion-resistant seamless metal tubes. The foaming powder is obtained by mixing metal powder, tackifier and foaming agent powder in proportion.

[0023] Step S2: extruding the inner metal tube, the outer metal tube and the foaming powder as a whole to obtain a composite tube blank; The foaming powder is compacted to form a ring-shaped prefabricated foam blank, such as Figure 3 As shown, the composite tube blank 1 includes, from inside to outside, an inner metal tube 11 , an annular prefabricated foam blank 13 and an outer metal tube 12 .

[0024] Step S3: heating the tube blank composite tube blank to a target temperature, and rolling the tube blank composite tube blank through a three-roller inclined rolling mill, so that the temperature of the contact interface between the structures of the tube blank composite tube blank is increased to a preset temperature during the forming process, and the preset temperature is greater than or equal to the melting point temperature of the foaming powder, and the contact interface forms a target bonding interface of metallurgical bonding, so as to obtain a target composite tube blank; Step S4: placing the target composite tube blank in a heating furnace to foam the middle layer of the target composite tube blank to form a foam metal layer, thereby obtaining a foam metal sandwich composite tube.

[0025] The metal in the foam metal layer can be aluminum, copper, iron, nickel, titanium or stainless steel, etc., which are metals or alloys that can form stable bubbles by heating and foaming.

[0026] Specifically, the target composite tube blank is placed in a heating furnace at a third target temperature for a certain period of time. During the heating process, the foaming agent decomposes to generate bubbles, and the annular prefabricated foam blank in the middle layer of the target composite tube blank forms a foam metal layer. After the insulation is completed, a foam metal sandwich composite tube with a metallurgical bonding interface is obtained. The third target temperature is greater than or equal to the foaming temperature of the foaming powder. Figure 6 As shown, the foam metal sandwich composite tube includes an inner metal tube, a foam metal layer and an outer metal tube from the inside to the outside, wherein the foam metal layer is formed by foaming an annular prefabricated foam blank, and the target bonding interface between the inner metal tube, the foam metal layer and the outer metal tube is a metallurgical bonding.

[0027] It can be known from the above method that the above step S2 realizes the preparation of the annular prefabricated foaming blank and the set blank assembly at the same time, which improves the set blank assembly efficiency, and the various structures of the obtained tube blank composite tube blank are tightly combined, avoiding the phenomenon that the gap set causes the different layers of tube blanks to be dislocated during the subsequent rolling and compounding process, resulting in the failure of the combination; during the preparation process, in step S4, since the temperature of the contact interface is the preset temperature reached by the deformation heat, the temperature rise will not be particularly large, and the temperature of the contact interface can reach the melting point temperature but not reach the foaming temperature of the middle layer of the tube blank composite tube blank. The middle layer of the tube blank composite tube blank will not foam during the rolling and compounding process, so the various structures of the tube blank composite tube blank are more tightly combined under the rolling action. The foam metal sandwich composite tube prepared by the above method has two kinds of seamless metal tubes with high corrosion resistance as the inner layer and the outer layer, and the core layer is filled with foam metal. This foam metal sandwich composite tube has high strength, high stability, high corrosion resistance, and excellent sound absorption and vibration reduction performance. The hydraulic actuator shell prepared based on this material not only has light weight, high strength and excellent sound absorption and vibration reduction performance, but also can maintain excellent performance in extreme environments such as deep sea high pressure, low temperature, and high salt, thus meeting the urgent demand for high-performance functional shell materials for deep-sea hydraulic actuators.

[0028] Based on the above method, the present invention also provides some specific implementation methods, which are described in detail below.

[0029] The composite tube blank in step S2 can be prepared by using a tube blank set mold, such as Figure 2 As shown, the tube blank set mold includes: a tube blank forming inner mold 21, a tube blank forming outer mold 22, an annular pressure head 24 and an oscillating base 23; the tube blank forming inner mold 21 is a cylindrical structure, the tube blank forming outer mold 22 is sleeved on the outer surface of the tube blank forming inner mold 21, a cavity is formed between the tube blank forming inner mold 21 and the tube blank forming outer mold 22, and the lower surface of the tube blank forming inner mold 21 and the lower surface of the tube blank forming outer mold 22 are connected to the upper surface of the oscillating base 23. Step S2 may specifically include: The inner metal tube 11 and the outer metal tube 12 are placed in the cavity formed by the outer tube forming die 22 and the inner tube forming die 21, and the foaming powder is poured into the gap between the inner metal tube 11 and the outer metal tube 12; the inner metal tube 11 is placed on the side close to the inner tube forming die 21, and the outer metal tube 12 is placed on the side close to the outer tube forming die 22; The oscillating base 23 of the tube blank set mold is started, and the annular pressing head 24 is used to press the foaming powder into an annular prefabricated foam blank 13 during the oscillation process of the oscillating base 23 to obtain a tube blank composite tube blank consisting of an inner metal tube 11, an annular prefabricated foam blank 13 and an outer metal tube 12.

[0030] The inner metal tube 11, the annular prefabricated foaming blank 13 and the outer metal tube 12 of the composite tube blank prepared by the above method are tightly combined without any gap.

[0031] As an optional method, before step S4, the following steps are further included: According to formula (1): (1) Calculating and obtaining the target temperature; in, is the target temperature, is the melting point of the foaming powder, is the specific heat capacity of the inner metal tube or the specific heat capacity of the outer metal tube, is the density of the inner metal tube or the density of the outer metal tube, is the deformation amount of the composite tube billet.

[0032] When the materials of the inner metal tube and the outer metal tube are different, the heating temperatures are different. The target temperature calculated based on the density and specific heat capacity of the inner metal tube is the first target temperature, and the target temperature calculated based on the density and specific heat capacity of the outer metal tube is the second target temperature; both the first target temperature and the second target temperature are lower than the melting point temperature.

[0033] See also Figure 4 and Figure 5 The target composite tube billet in the above step S3 is prepared by a rolling tool, which includes: a three-roller oblique rolling mill 42 and a mandrel 41, a first induction heating coil 411 is arranged in the mandrel 41, a second induction heating coil 43 is fixed at the rolling mill entrance of the three-roller oblique rolling mill 42, the mandrel 41 passes through the second induction heating coil 43 and the oblique rolling hole of the three-roller oblique rolling mill 42, and the second induction heating coil 43 is sleeved on one end of the mandrel 41 provided with the first induction heating coil 411.

[0034] As an optional method, step S3 can be implemented by the following steps: The composite tube blank 1 is put onto the mandrel 41, and the composite tube blank 1 is placed between the first induction heating coil 411 and the second induction heating coil 43; The first induction heating coil 411 is started to heat the temperature of the inner metal tube in the tube blank composite tube blank 1 to the first target temperature; the second induction heating coil 43 is started to heat the outer metal tube in the tube blank composite tube blank 1 to the second target temperature; The mandrel trolley is used to drive the mandrel 41 to move along the axial direction of the mandrel 41, so that the mandrel 41 and the tube blank composite tube blank 1 enter the oblique rolling hole; The rollers of the three-roller oblique rolling mill 42 are used to reduce the diameter and wall of the tube blank composite tube blank 1 in the radial direction; the contact interface between the various structures of the tube blank composite tube blank 1 is heated to a preset temperature under the action of rolling; the preset temperature is greater than or equal to the melting point of the foaming powder, so that the contact interface is remelted to form a target bonding interface for metallurgical bonding, thereby obtaining a target composite tube blank.

[0035] In the above steps, independent induction heating coils are used to perform induction heating on different metal tubes at the same time, so that precise temperature control before rolling is achieved, ensuring that the material of the inner metal tube and the material of the outer metal tube layer at high temperature are similar to the deformation resistance of the annular prefabricated foam blank at room temperature, effectively avoiding oxidation of the contact interface to be composited during the heating process, and achieving coordinated deformation, which greatly improves the success rate and stability of the preparation of the target composite tube blank. The different first target temperature and second target temperature are set to be less than and close to the melting point temperature of the annular prefabricated foam blank. The temperature rise in the rolling composite deformation is used to make the contact interface temperature exceed the melting point temperature of the annular prefabricated foam blank, so that the interface remelting during the rolling composite deformation process can form a metallurgical bond, and at the same time, it can avoid the excessive temperature of the annular prefabricated foam blank leading to premature foaming, ensuring precise control of the foaming process.

[0036] After step S4, the present invention also provides a method for preparing a hydraulic actuator housing based on a foam metal sandwich composite tube, comprising the following steps: Step S5: providing a composite plate blank; the composite plate blank comprises, from top to bottom, a first corrugated metal plate, a square prefabricated foam blank and a second corrugated metal plate; the first corrugated metal plate and the second corrugated metal plate are corrugated metal plates with a corrugated interface on one side; The steps for preparing the composite slab are: Two metal plates and foaming powder are provided; Put the foaming powder into the square inner cavity formed by the square mold, start the oscillation base, and press the foaming powder into a square prefabricated foam blank through the directional pressing head; A corrugated rolling mill is used to roll two metal plates to obtain a first corrugated metal plate and a second corrugated metal plate, wherein the first corrugated metal plate and the second corrugated metal plate are both corrugated metal plates with a corrugated interface on one side; the upper roller of the corrugated rolling mill is a corrugated roller, and the lower roller is a flat roller; The first corrugated metal sheet, the square prefabricated foam blank and the second corrugated metal sheet are assembled in this order to obtain a composite sheet blank, wherein the square prefabricated foam blank contacts the corrugated interface of the first corrugated metal sheet and the corrugated interface of the second corrugated metal sheet. The obtained composite sheet blank has a sandwich structure. The foaming powder used to prepare the square prefabricated foam blank is the same as the foaming powder used to prepare the annular prefabricated foam blank.

[0037] Step S6: Use an induction heating device to heat the composite plate blank, a third induction heating coil is provided on the top of the inner surface of the induction heating device, and a fourth induction heating coil is provided on the bottom of the inner surface of the induction heating device, the third induction heating coil is used to heat the first corrugated metal plate to a first target temperature, and the fourth induction heating coil is used to heat the second corrugated metal plate to a second target temperature to obtain a different-temperature composite plate blank; the material of the first corrugated metal plate is the same as the material of the inner metal tube, and the material of the second corrugated metal plate is the same as the material of the outer metal tube.

[0038] Step S7: rolling the different-temperature composite plate blank so that the first corrugated metal plate, the second corrugated metal plate and the square prefabricated foam blank are tightly bonded, and the temperature of the contact interface between the structures of the different-temperature composite plate blank is increased to a preset temperature, which is greater than or equal to the melting point temperature, so that the contact interface between the structures of the different-temperature composite plate blank is remelted to form a metallurgical bonding interface, thereby obtaining a target composite plate; Step S8: placing the target composite panel in a heating furnace at a third target temperature for a preset time, so that a foam metal layer is formed in the middle layer of the target composite panel, thereby obtaining a foam metal sandwich composite panel; Step S9: cutting the foam metal sandwich composite panel according to preset dimensions to obtain two foam metal sandwich flanges and two foam metal sandwich end covers.

[0039] The foam metal sandwich flange and the foam metal sandwich end cover prepared by the above steps have high strength, high stability, high corrosion resistance, and excellent sound absorption and vibration reduction performance.

[0040] Step S10: Assembling the foam metal sandwich composite tube, the foam metal sandwich end cover and the foam metal sandwich end cover to obtain a hydraulic actuator housing.

[0041] Specifically, the hydraulic actuator housing is assembled by welding the foam metal sandwich flange to the two ends of the foam metal sandwich composite tube respectively; the first through hole and the second through hole are matched one by one, and bolts are passed through the first through hole and the second through hole to fasten the foam metal sandwich flange and the foam metal sandwich end cover.

[0042] The hydraulic actuator housing prepared by the above method includes a foam metal sandwich composite tube, a foam metal sandwich flange and a foam metal sandwich end cover; the number of the foam metal sandwich flange and the foam metal sandwich end cover are both 2, one foam metal sandwich flange is welded to one end of the foam metal sandwich composite tube, and the other foam metal sandwich flange is welded to the other end of the foam metal sandwich composite tube, and the foam metal sandwich flange and the foam metal sandwich end cover are fastened by bolts.

[0043] The bonding interface between the various structures of the foam metal sandwich flange is a metallurgical bonding interface, and the bonding interface between the various structures of the foam metal sandwich end cover is a metallurgical bonding interface. The surface layers of the foam metal sandwich flange and the foam metal sandwich end cover are two high-strength and corrosion-resistant metal sheets, and the core layer is filled with foam metal.

[0044] Among them, the foam metal sandwich flange is an annular cylindrical structure, the foam metal sandwich end cover is a cylindrical structure, the outer diameter of the foam metal sandwich flange is the same as the diameter of the foam metal sandwich end cover, and 6 first through holes are evenly arranged on the annular surface of the foam metal sandwich flange along the circumferential direction, and 6 second through holes corresponding to the first through holes are arranged on the circular surface of the foam metal sandwich end cover.

[0045] Next, a method for preparing a composite pipe for vibration reduction and noise reduction provided by the present invention is described in detail by way of example.

[0046] The prepared composite tube has an inner metal tube made of 304 stainless steel and an outer metal tube made of TA's 304 / TA2 foam metal sandwich composite tube. The preparation method comprises the following steps: Step 11: Preparation of foaming powder: Select metal Ca as a thickener and titanium metal hydride as a foaming agent powder, pre-oxidize the foaming agent powder to delay its decomposition rate during the heating and foaming process, and mix the aluminum alloy powder, thickener and foaming agent powder in a mass percentage of 95%, 3% and 2% to obtain a foaming powder.

[0047] Step 12: Assembly: Select 304 stainless steel seamless tubes with an outer diameter of 200mm, a wall thickness of 10mm, and a length of 500mm and TA2 seamless tubes with an outer diameter of 140mm, a wall thickness of 10mm, and a length of 500mm. Use alcohol to clean and remove oil stains, then grind the inner surface of the 304 stainless steel seamless tube and the outer surface of the TA2 seamless tube, install them in the tube set mold, and then fill the gap between the TA2 seamless tube and the 304 stainless steel seamless tube with foaming powder, compact the foaming powder with an annular pressure head, and finally obtain a 304 / TA2 foam aluminum sandwich tube composite tube blank. During the assembly process, the oscillating base works continuously to ensure that a compact foam aluminum sandwich composite blank is obtained; Step 13: Calculate the first target temperature and the second target temperature, wherein the deformation of the 304 / TA2 foam aluminum sandwich tube composite tube blank during the rolling composite process is 25%, the density of 304 stainless steel is 7.93 g / cm3, the specific heat capacity is 0.5 J / g, the density of TA2 is 4.51 g / cm3, the specific heat capacity is 0.526 J / g, and the melting point of the foaming powder is 660°C. Substituting these values ​​into formula (1), the first target temperature is calculated to be 550°C and the second target temperature is 600°C.

[0048] Step 14: Electromagnetic induction heating of the composite billet: Insert the 304 / TA2 foam aluminum sandwich tube composite billet into the mandrel, turn on the first induction heating coil and the second induction heating coil, heat the 304 stainless steel seamless tube and TA2 seamless tube to the rolling temperature of 600℃ and 550℃ respectively. The rolling temperatures are both lower than the melting point of the annular prefabricated foamed billet of 660℃. Due to the lower thermal conductivity and higher coefficient of expansion of titanium, it is easier to absorb heat and heat up rapidly during the rolling process. Under the same conditions, titanium usually heats up faster than stainless steel, so the TA2 seamless tube sets a higher rolling temperature than the 304 stainless steel seamless tube.

[0049] Step 15: rolling and compounding: after heating is completed, the electromagnetic induction device is turned off and the three-roller oblique rolling mill is started. The mandrel trolley drives the mandrel to move forward, and the mandrel and the 304 / TA2 aluminum foam sandwich tube composite tube blank are simultaneously fed into the oblique rolling hole shape. The 304 / TA2 composite tube blank rotates forward around the mandrel under the drive of the rollers, and is pressed down and compounded at the same time. After cooling, a seamless metal tube blank is finally obtained; the set hole diameter is 170mm, and the mandrel diameter is 110mm. Under the action of rolling deformation, the deformation heat causes the contact interface temperature of the TA2 seamless tube and the 304 stainless steel seamless tube and the annular prefabricated foam blank to rise to a temperature exceeding the melting point of the annular prefabricated foam blank, so that the interface is remelted to form a metallurgical bond, but the annular prefabricated foam blank does not reach the foaming temperature of 550°C and pre-foaming does not occur; Step 16: rolling and compounding: the seamless metal tube blank prepared in step 15 is placed in a heating furnace at a temperature of 550°C and kept warm for 3 minutes. During the heating process, the annular prefabricated foam blank decomposes to produce bubbles, and the prefabricated foam blank of the middle layer forms foamed metal aluminum. After the insulation and foaming are completed, the end is cut off to obtain a 304 / TA2 foamed aluminum sandwich composite tube with interface metallurgical bonding.

[0050] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

Claims

1. A method for preparing a composite pipe for vibration and noise reduction, characterized in that: include: Provide inner metal tube, outer metal tube and foaming powder; The inner metal tube, the outer metal tube and the foaming powder are extruded into a single body to obtain a composite tube blank; The tube blank composite tube blank is heated to a target temperature, and the tube blank composite tube blank is rolled into shape by a three-roller inclined rolling mill, so that the temperature of the contact interface between the structures of the tube blank composite tube blank is increased to a preset temperature during the forming process, and the preset temperature is greater than or equal to the melting point temperature of the foaming powder, and the contact interface forms a target bonding interface of metallurgical bonding to obtain a target composite tube blank; the target temperature is less than the melting point temperature; The target composite tube blank is placed in a heating furnace to foam the middle layer of the target composite tube blank to form a foam metal layer, thereby obtaining a foam metal sandwich composite tube.

2. The method for preparing a composite pipe for vibration and noise reduction according to claim 1, characterized in that: The inner metal tube, the outer metal tube and the foaming powder are extruded integrally to obtain a composite tube blank, which comprises: The inner metal tube and the outer metal tube are placed in a cavity formed by a tube blank forming outer die and a tube blank forming inner die, and the foaming powder is poured into the gap between the inner metal tube and the outer metal tube; the inner metal tube is placed on a side close to the tube blank forming inner die, and the outer metal tube is placed on a side close to the tube blank forming outer die; The oscillating base of the tube blank set mold is started, and the foaming powder is compacted into an annular prefabricated foam blank by using an annular pressing head during the oscillation process of the oscillating base to obtain a tube blank composite tube blank.

3. The method for preparing a composite pipe for vibration and noise reduction according to claim 1, characterized in that: The target composite tube billet is prepared by a rolling tool, which includes: a three-roller oblique rolling mill and a mandrel, wherein a first induction heating coil is arranged in the mandrel, a second induction heating coil is fixed at the rolling mill entrance of the three-roller oblique rolling mill, the mandrel passes through the second induction heating coil and the oblique rolling hole of the three-roller oblique rolling mill, and the second induction heating coil is sleeved on one end of the mandrel where the first induction heating coil is arranged.

4. The method for preparing a composite pipe for vibration and noise reduction according to claim 3, characterized in that: The target temperature includes a first target temperature and a second target temperature; the tube blank composite tube blank is heated to the target temperature, and the tube blank composite tube blank is rolled and formed by a three-roller inclined rolling mill, so that the temperature of the contact interface between the structures of the tube blank composite tube blank is increased to a preset temperature during the forming process, and the preset temperature is greater than or equal to the melting point temperature of the foaming powder, and the contact interface forms a target bonding interface for metallurgical bonding, and obtaining the target composite tube blank includes: Sleeving the tube blank composite tube onto the mandrel, and placing the tube blank composite tube between the first induction heating coil and the second induction heating coil; Starting the first induction heating coil to heat the temperature of the inner metal tube to a first target temperature; starting the second induction heating coil to heat the outer metal tube to a second target temperature; Using a mandrel trolley to drive the mandrel to move along the axial direction of the mandrel, so that the mandrel and the tube blank composite tube blank enter the oblique rolling hole; The rollers of the three-roller oblique rolling mill are used to reduce the diameter and wall of the composite tube billet in the radial direction; the contact interface between the various structures of the composite tube billet is heated to a preset temperature under the action of rolling; the preset temperature is greater than or equal to the melting point of the foaming powder, so that the contact interface is remelted to form a target bonding interface for metallurgical bonding, thereby obtaining a target composite tube billet.

5. The method for preparing a composite pipe for vibration and noise reduction according to claim 1, characterized in that: Before heating the tube blank composite tube blank to the target temperature, the method further comprises: According to the formula: ； Calculating and obtaining the target temperature; in, is the target temperature, is the melting point of the foaming powder, is the specific heat capacity of the inner metal tube or the specific heat capacity of the outer metal tube, is the density of the inner metal tube or the density of the outer metal tube, is the deformation amount of the composite tube billet.

6. The method for preparing a composite pipe for vibration and noise reduction according to claim 2, characterized in that: The tube blank set mold comprises: a tube blank forming inner mold, a tube blank forming outer mold, an annular pressure head and an oscillating base; the tube blank forming inner mold is a cylindrical structure, the tube blank forming outer mold is sleeved on the outer surface of the tube blank forming inner mold, a cavity is formed between the tube blank forming inner mold and the tube blank forming outer mold, and the lower surface of the tube blank forming inner mold and the lower surface of the tube blank forming outer mold are respectively connected to the upper surface of the oscillating base.

7. The method for preparing a composite pipe for vibration and noise reduction according to claim 1, characterized in that: The foam metal sandwich composite tube comprises an inner metal tube, a foam metal layer and an outer metal tube from the inside to the outside; the target bonding interface between the inner metal tube, the foam metal layer and the outer metal tube is a metallurgical bonding interface.

Images