Preparation method and tool of hydraulic actuator shell and hydraulic actuator shell

Abstract

The invention discloses a preparation method and tool of a hydraulic actuator shell and the hydraulic actuator shell, relates to the field of metal material preparation, and aims to solve the problem that the interior of the shell cannot bear environmental high pressure in deep sea. The preparation method comprises the following steps: providing a composite tube blank which sequentially comprises an aluminum alloy layer, a first adhesive film layer, a carbon fiber layer, a second adhesive film layer and a stainless steel layer from inside to outside; heating the composite pipe blank, sleeving the composite pipe blank on an inner die, pushing the inner die to drive the composite pipe blank to penetrate through an annular die cavity formed by the inner die and an outer die to perform extrusion forming on the composite pipe blank in the radial direction, so that the aluminum alloy layer, the carbon fiber layer and the stainless steel layer are tightly combined; curing the composite pipe blank in a vacuum environment to obtain a composite pipe; and the two ports of the composite pipe are connected with the composite flanges correspondingly, the side, away from the composite pipe, of each composite flange is connected with the corresponding composite end cover, and the composite shell is obtained.

Description

Technical Field

[0001] The invention relates to the field of metal material preparation, and in particular to a preparation method of a hydraulic actuator housing, a tool and a hydraulic actuator housing. Background Art

[0002] In deep-sea equipment, personnel and many core components need to rely on sturdy shells for protection. The extreme environment of deep-sea high pressure, low temperature, high salt, etc. has high requirements on the overall performance of the marine equipment shell. Traditional deep-sea hydraulic actuator shells are usually made of a single metal material, such as stainless steel or titanium alloy. This metal material has high strength and good corrosion resistance, but the density of stainless steel and titanium alloy is relatively large, resulting in a heavier overall weight of the shell, affecting the operational flexibility and fuel efficiency of the equipment; at the same time, these metal materials are prone to vibration and noise in the deep-sea high-pressure environment, affecting the stability and reliability of the equipment.

[0003] Composite materials have excellent mechanical properties and lightweight characteristics, which can significantly improve the strength of the shell and reduce the weight. Carbon fiber reinforced polymer (CFRP) is a high-performance composite material. Due to its high strength, high modulus, low density and good corrosion resistance, using carbon fiber reinforced polymer (CFRP) alone as a shell material also has the problem of relatively poor impact resistance and sealing of carbon fiber reinforced polymer (CFRP), which cannot adapt to the high-pressure environment of the deep sea environment. Summary of the invention

[0004] The object of the present invention is to provide a method for preparing a hydraulic actuator housing, a tool and a hydraulic actuator housing, which are used to improve the ability of the interior of the composite housing to withstand working pressure and improve the shock and sound absorption performance in a deep sea environment.

[0005] In order to achieve the above object, the present invention provides the following technical solutions: In a first aspect, the present invention provides a method for preparing a hydraulic actuator housing, which is used to prepare a closed housing having a composite pipe, a composite flange and a composite end cover, and the preparation method comprises: A composite tube blank is provided, wherein the composite tube blank comprises, from inside to outside, an aluminum alloy layer, a first adhesive film layer, a carbon fiber layer, a second adhesive film layer and a stainless steel layer; The composite tube blank is heated, and an inner die is placed in the composite tube blank, and the inner die is pushed to drive the composite tube blank through the annular die cavity composed of the inner die and the outer die to extrude the composite tube blank in the radial direction, so that the aluminum alloy layer, the carbon fiber layer and the stainless steel layer are tightly combined; placing the composite tube blank in a vacuum temperature-controlled environment for curing to obtain a composite tube; The two ends of the composite pipe are respectively connected to a composite flange, and the side of each composite flange away from the composite pipe is connected to a composite end cover to obtain a composite shell.

[0006] Optionally, in the above-mentioned method for preparing the hydraulic actuator housing, the method for preparing the composite flange and the composite end cover comprises: Providing a composite slab, the composite slab comprising, from bottom to top, an aluminum alloy layer, a first adhesive film layer, a carbon fiber layer, a second adhesive film layer and a stainless steel layer; The composite slab is subjected to vacuum treatment by a vacuum device; placing the composite slab blank in a vacuum temperature-controlled environment for curing to obtain a composite plate; The composite plate is cut to obtain a composite flange and a composite end cap.

[0007] Optionally, in the above method for preparing the hydraulic actuator housing, the vacuum device comprises a template, a demoulding cloth, an isolation film, a vacuum nozzle, a vacuum bag, a vacuum pump, a breathable felt and a high temperature resistant rubber strip; The vacuum treatment of the composite slab by the vacuum device includes: Spray release agent on the formwork; A demoulding cloth, a composite slab, an isolation film, a breathable felt and a vacuum bag are sequentially stacked on the template, and the breathable felt is also arranged around the side of the composite slab. The composite slab is isolated from the vacuum bag by the isolation film and the breathable felt. The vacuum bag and the template are sealed and connected by a high-temperature resistant rubber strip to form a working chamber, and the working chamber is connected to a vacuum pump through a vacuum nozzle; The working chamber is evacuated by a vacuum pump.

[0008] Optionally, in the method for preparing the hydraulic actuator housing, curing the composite tube blank in a vacuum temperature-controlled environment and curing the composite plate blank in a vacuum temperature-controlled environment both include: Putting the composite tube blank or composite plate blank into an autoclave; Evacuate the autoclave to a pressure of -0.90MPa~-1.00MPa; Maintain a heating rate of 0.8°C / min~1.2°C / min to raise the temperature in the autoclave to 80°C~90°C, and keep the temperature for 25min~35min to complete the heating pre-curing of the composite tube or composite slab; Continue to maintain a heating rate of 0.8°C / min~1.2°C / min, so that the pressure value in the autoclave reaches 0.45MPa~0.55MPa, and when the temperature rises to 120°C~130°C, keep the temperature and pressure for 85min~95min to complete the insulation and pressure maintenance of the composite tube or composite plate for full solidification; The pressure value in the autoclave is reduced to normal atmospheric pressure, and the temperature is reduced to 35°C~45°C, completing the cooling and pressure reduction solidification of the composite tube blank or composite plate blank to obtain a composite tube or composite plate.

[0009] Optionally, in the method for preparing the hydraulic actuator housing, heating the composite tube blank, and placing an inner die in the composite tube blank, pushing the inner die to drive the composite tube blank through the annular die cavity formed by the inner die and the outer die to extrude the composite tube blank in the radial direction comprises: The composite tube blank is placed in an annular mold cavity of a mold consisting of an inner mold and an outer mold; The composite tube blank is heated to a target extrusion temperature of 350°C to 450°C by an electronic induction coil arranged in the outer die; The outer die is fixed by an extruder, and one end of the inner die is pushed by a pressure head to move along the axial direction of the composite tube blank, so that the composite tube blank is extruded from the extrusion end of the annular die cavity, and the extrusion end is used to apply radial pressure to the composite tube blank.

[0010] Optionally, in the method for preparing the hydraulic actuator housing, the carbon fiber layer is formed by laying multiple layers of carbon fiber woven cloth alternately at angles of 0° and 90°.

[0011] Compared with the prior art, when the above technical solution is adopted, the aluminum alloy layer, the first film layer, the carbon fiber layer, the second film layer and the stainless steel layer are placed in sequence from the inside to the outside to form a composite tube blank, and then the composite tube blank is heated, and the composite tube blank is extruded radially by the inner mold and the outer mold, so that the aluminum alloy layer, the carbon fiber layer and the stainless steel layer are tightly combined, and then the extruded composite tube blank is placed in a vacuum environment for curing to obtain a composite tube, and finally the two ends of the composite tube are welded to a composite flange respectively, and the side of each composite flange away from the composite tube is bolted to a composite end cover to obtain a composite shell. Compared with the existing shell prepared by a single layer of material, the present application respectively arranges the first film layer between the aluminum alloy layer and the carbon fiber layer, and arranges the second film layer between the carbon fiber layer and the stainless steel layer, and then performs temperature controlled extrusion forming, vacuum curing and other processes, so that the layers of materials are tightly connected, thereby ensuring that the formed composite shell has high strength and can withstand the pressure in the deep sea environment, and at the same time has excellent vibration reduction and sound absorption performance, which can effectively reduce the vibration and noise generated by the hydraulic actuator when working in the composite shell, so as to improve the stability and reliability of the equipment.

[0012] In a second aspect, the present invention further provides a preparation tool for a hydraulic actuator housing, which is used for extruding a composite tube blank in any of the above-mentioned preparation methods for a hydraulic actuator housing, and the preparation tool comprises: The inner mold is a T-shaped structure having a head and a tail. The tail of the T-shaped structure is a positioning end of the inner mold, and the tail of the T-shaped structure is placed in the composite tube blank; An outer mold, wherein an electromagnetic induction coil is arranged inside the outer mold, and the electromagnetic induction coil is used to heat the composite tube blank. The inner wall of the outer mold has a large diameter section, a slope section and a small diameter section, and the large diameter section and the small diameter section are transitionally connected by the slope section. The large diameter section of the outer mold is sleeved with the head of the inner mold, and an annular mold cavity is formed between the inner wall of the outer mold and the tail of the inner mold. The annular mold cavity is used to place the composite tube blank, and one end of the annular mold cavity close to the small diameter section has an extrusion end; An extruder, used to clamp and fix the outer wall of the outer mold; The pressure head is used to push the head of the inner die to extrude the composite tube billet and move it along the axis of the composite tube billet toward the extrusion end.

[0013] Optionally, the preparation tooling of the hydraulic actuator housing further includes a water circulation component, which is spirally wound and arranged in the inner mold, and is used to cool the inner mold.

[0014] Compared with the prior art, the beneficial effects of the preparation tooling for the hydraulic actuator housing provided by the present invention are the same as the beneficial effects of the preparation method for the hydraulic actuator housing of any of the above technical solutions, which will not be elaborated here.

[0015] In a third aspect, the present invention further provides a hydraulic actuator housing, comprising: Composite pipe; Two composite flanges, one of which is welded to one end of the composite pipe, and the other composite flange is welded to the other end of the composite pipe; Two composite end covers, the composite end covers and the composite flanges are connected one by one through bolts, the composite end covers and the composite pipes form a closed space, and the composite pipes, the composite flanges and the composite end covers all have stainless steel layers, carbon fiber layers and aluminum alloy layers arranged from outside to inside.

[0016] Optionally, in the hydraulic actuator housing, the carbon fiber layer includes CFRP composite material prepreg or GFRP composite material prepreg.

[0017] Compared with the prior art, when the above technical solution is adopted, a composite pipe, a composite flange and a composite end cover having a stainless steel layer, a carbon fiber layer and an aluminum alloy layer arranged from the outside to the inside are connected to form a closed space. Compared with the traditional method of using a single material as the shell material, the present application arranges the stainless steel layer, the carbon fiber layer and the aluminum alloy layer in sequence from the outside to the inside, so that the formed closed space can adapt to the high-pressure environment in the deep sea, thereby ensuring the reliable operation of the hydraulic actuator in the hydraulic actuator housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] 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 process flow chart of a method for preparing a hydraulic actuator housing provided in an embodiment of the present invention; Figure 2 A schematic diagram of laying carbon fiber layers in step S100 in a method for preparing a hydraulic actuator housing provided in an embodiment of the present invention; Figure 3 It is a structural schematic diagram of forming a composite tube blank in step S100 in a method for preparing a hydraulic actuator housing provided in an embodiment of the present invention; Figure 4 for Figure 3 sectional view of Figure 5 It is a schematic structural diagram of a composite tube formed after step S300 in a method for preparing a hydraulic actuator housing provided in an embodiment of the present invention; Figure 6 for Figure 5 sectional view of Figure 7 A schematic diagram of the structure of a tooling for preparing a hydraulic actuator housing provided in an embodiment of the present invention; Figure 8 A schematic structural diagram of an inner mold of a tooling for preparing a hydraulic actuator housing provided in an embodiment of the present invention; Fig. 9 for Figure 8 AA section view; Fig.10 A schematic structural diagram of an outer mold of a tooling for preparing a hydraulic actuator housing provided in an embodiment of the present invention; Fig.11 for Fig.10 Schematic diagram of the structure of the electromagnetic induction coil; Fig.12 It is a structural schematic diagram of the operation of step S502 in a method for preparing a hydraulic actuator housing provided in an embodiment of the present invention; Fig.13 It is a schematic structural diagram of a composite flange in a hydraulic actuator housing provided in an embodiment of the present invention; Fig.14 for Fig.13 BB section view; Fig.15 It is a schematic structural diagram of a composite end cover in a hydraulic actuator housing provided in an embodiment of the present invention; Fig.16 for Fig.15 CC section view; Fig.17 It is a schematic structural diagram of a hydraulic actuator housing provided in an embodiment of the present invention.

[0019] Reference numerals: 1-composite tube; 11-composite tube blank; 2-composite plate blank; 21-composite flange; 22-composite end cover; 23-sealing component; 3-aluminum alloy layer; 4-carbon fiber layer; 5-stainless steel layer; 6-vacuum device; 601-template; 602-mold release cloth; 603-isolating film; 604-vacuum bag; 605-breathable felt; 606-high temperature resistant rubber strip; 7-inner mold; 71-head; 72-tail; 73-water circulation component; 731-water inlet; 732-water outlet; 8-outer mold; 81-electromagnetic induction coil; 82-large diameter section; 83-slope section; 84-small diameter section; 85-insulating ring; 86-insulating strip; 87-fastening screw; 88-outer mold end cover; 91-extruder; 92-pressing head; 93-graphite gasket. DETAILED DESCRIPTION

[0020] 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 intended to limit the present invention.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] like Figure 1-Figure 17 As shown, a method for preparing a hydraulic actuator housing provided by an embodiment of the present invention is used to prepare a closed housing having a composite pipe 1, a composite flange 21 and a composite end cover 22, and the preparation method includes: Step S100, as Figure 3-Figure 6 As shown, a composite tube blank 11 is provided, and the composite tube blank 11 includes an aluminum alloy layer 3, a first adhesive film layer, a carbon fiber layer 4, a second adhesive film layer and a stainless steel layer 5 from the inside to the outside; In step S100, the operator first lays a first film layer on the outer wall of the aluminum alloy tube, covers the surface of the first film layer with a carbon fiber layer 4 to form a tube blank, continues to lay a second film layer on the outer wall surface of the tube blank, and nests the tube blank gap in the inner wall of the stainless steel tube to obtain a composite tube blank 11, so that the composite tube blank 11 is distributed from the inner wall to the outer wall in sequence as an aluminum alloy layer 3, a carbon fiber layer 4 and a stainless steel layer 5, so as to facilitate the extrusion forming of the composite tube blank 11.

[0026] Step S200, as Figure 7 As shown, the composite tube blank 11 is heated, and an inner die 7 is placed in the composite tube blank 11, and the inner die 7 is pushed to drive the composite tube blank 11 to pass through the annular die cavity formed by the inner die 7 and the outer die 8 to extrude the composite tube blank 11 in the radial direction, so that the aluminum alloy layer 3, the carbon fiber layer 4 and the stainless steel layer 5 are tightly combined; Step S300, placing the composite tube blank 11 in a vacuum temperature-controlled environment for curing to obtain a composite tube 1; Step S400, as Fig.17 As shown, the two ends of the composite pipe 1 are respectively connected to a composite flange 21, and the side of each composite flange 21 away from the composite pipe 1 is connected to a composite end cover 22 to obtain a composite shell.

[0027] When implementing it, Figure 1As shown, the aluminum alloy layer 3, the first adhesive film layer, the carbon fiber layer 4, the second adhesive film layer and the stainless steel layer 5 are placed in sequence from the inside to the outside to form a composite tube blank 11, wherein a 304 stainless steel seamless tube with an outer diameter of 200 mm, a wall thickness of 5 mm and a length of 500 mm, a 5052 aluminum alloy seamless tube with an outer diameter of 180 mm, a wall thickness of 5 mm and a length of 500 mm can be selected, and the carbon fiber layer 4 is a T300 carbon fiber epoxy resin prepreg. Here, the aluminum alloy layer 3, the carbon fiber layer 4 and the stainless steel layer 5 are not limited to the cases listed in this embodiment. Then, the composite tube blank 11 is heated, and the composite tube blank 11 is extruded radially by the inner mold 7 and the outer mold 8, so that the aluminum alloy layer 3, the carbon fiber layer 4 and the stainless steel layer 5 are tightly combined, and then the extruded composite tube blank 11 is placed in a vacuum environment. Curing to obtain a composite pipe 1, and finally connecting the two ends of the composite pipe 1 to a composite flange 21 respectively, and each composite flange 21 is connected to a composite end cover 22 on a side away from the composite pipe 1 to obtain a composite shell. Compared with the existing shell prepared by a single layer of material, the present application respectively arranges a first adhesive film layer between the aluminum alloy layer 3 and the carbon fiber layer 4, and arranges a second adhesive film layer between the carbon fiber layer 4 and the stainless steel layer 5, and then performs temperature-controlled extrusion molding, vacuum curing and other processes, so that the layers of materials are tightly connected, thereby ensuring that the formed composite shell has high strength and can withstand the pressure in the deep sea environment, and at the same time has excellent vibration reduction and sound absorption performance, which can effectively reduce the vibration and noise generated by the hydraulic actuator when working in the composite shell, so as to improve the stability and reliability of the equipment.

[0028] Specifically, in this embodiment, the preparation method of the composite flange 21 and the composite end cover 22 includes: Step S501, providing a composite slab 2, the composite slab 2 including, from bottom to top, an aluminum alloy layer 3, a first adhesive film layer, a carbon fiber layer 4, a second adhesive film layer and a stainless steel layer 5; In step S501, Fig.12 As shown, the operator first lays a first adhesive film layer on the aluminum alloy plate, covers the surface of the first adhesive film layer with a carbon fiber layer 4, continues to lay a second adhesive film layer on a side of the carbon fiber layer 4 away from the first adhesive film layer, and covers a stainless steel layer 5 on a side of the second adhesive film layer away from the carbon fiber layer 4 to form a composite slab 2, so that the composite slab 2 is sequentially distributed as an aluminum alloy layer 3, a carbon fiber layer 4 and a stainless steel layer 5 for easy installation.

[0029] Step S502, vacuuming the composite slab 2 by means of a vacuum device 6; Step S503, placing the composite slab 2 in a vacuum temperature-controlled environment for curing to obtain a composite plate; Step S504, as Figure 13-Figure 16As shown, the composite plate is cut to obtain a composite flange 21 and a composite end cap 22. The composite plate can be cut by water jet technology. Specifically, six circular holes are cut along the circumferential direction of a diameter of 210 mm on the surface of the composite plate to obtain the composite end cap 22. The diameter of the circular hole can be 6 mm, 8 mm, 10 mm, etc. In addition, a circular plate with a diameter of 160 mm is cut and removed at the distribution center of the multiple circular holes to obtain the composite flange 21. The number and diameter of the circular holes and the diameter of the circular plate are not limited to those listed in this embodiment.

[0030] During operation, the aluminum alloy layer 3, the first adhesive film layer, the carbon fiber layer 4, the second adhesive film layer and the stainless steel layer 5 are placed in sequence from the inside to the outside to form a composite slab 2, and then the composite slab 2 is evacuated by a vacuum device 6 to remove bubbles generated after the layers of materials are stacked, and then the processed composite slab 2 is placed in a vacuum environment for curing to obtain a composite plate, and finally the composite plate is cut to obtain a composite flange 21 and a composite end cover 22, thereby improving the processing efficiency of the composite end cover 22 and the composite flange 21.

[0031] It should be noted that, before step S100 and before step S501, the surface of the stainless steel layer 5 and the surface of the aluminum alloy layer 3 need to be cleaned with alcohol, and then the surface to be bonded of the stainless steel layer 5 and the surface to be bonded of the aluminum alloy layer 3 are polished with a 60-mesh louver wheel, and finally, the surface of the stainless steel layer 5 and the surface of the aluminum alloy layer 3 are cleaned with acetone solution to remove the residual impurities, grease, water and other pollutants generated during the polishing process, so as to ensure the bonding effect between the stainless steel layer 5 and the carbon fiber layer 4 and between the aluminum alloy layer 3 and the carbon fiber layer 4, so as to ensure that the formed composite shell has good structural stability and reliability; at the same time, in step S1 00 and the first film layer and the second film layer in step S501 are both made of epoxy resin film. Of course, the first film layer and the second film layer can also be made of polyester resin film, polyimide film or other films. Here, the first film layer and the second film layer are not limited to the cases listed in this embodiment. Since the epoxy resin in the epoxy resin film is made of the same material as the epoxy resin in the carbon fiber layer 4, the composite tube blank 11 can be compatible to the greatest extent during the curing process of step S300 and the composite plate blank 2 can be compatible to the greatest extent during the curing process of step S503, ensuring that the aluminum alloy layer 3, the carbon fiber layer 4 and the stainless steel layer 5 are tightly bonded.

[0032] like Fig.12 As shown, in this embodiment, the vacuum device 6 includes a template 601, a demoulding cloth 602, an isolation film 603, a vacuum nozzle, a vacuum bag 604, a vacuum pump, a breathable felt 605 and a high temperature resistant rubber strip 606. The vacuum device 6 is used to vacuum the composite slab 2 in step S502, which specifically includes: Step S502a, spraying a release agent on the template 601; Step S502b, placing a demoulding cloth 602, a composite slab 2, an isolation film 603, a breathable felt 605 and a vacuum bag 604 on the template 601 in sequence, and the breathable felt 605 is also arranged around the side of the composite slab 2, the composite slab 2 is isolated from the vacuum bag 604 by the isolation film 603 and the breathable felt 605, the vacuum bag 604 and the template 601 are sealed and connected by a high temperature resistant rubber strip 606 to form a working chamber, and the working chamber is connected to the vacuum pump through a vacuum nozzle; Step S502c, evacuating the working chamber by using a vacuum pump.

[0033] From the description of the above structure and method, it can be known that the operator needs to first spray the release agent on the template 601 and lay the release cloth 602, and then place the composite slab 2, isolation membrane 603, breathable felt 605 and vacuum bag 604 on the release cloth 602 in sequence, and then continue to set the breathable felt 605 around the side of the composite slab 2 to isolate the composite slab 2 from the vacuum bag 604. At this time, the vacuum pump is connected to the vacuum nozzle, and the vacuum pump is used to evacuate the working chamber inside the vacuum bag 604 to remove bubbles generated after the layers of materials are stacked, to ensure that the aluminum alloy layer 3 and the carbon fiber layer 4, as well as the stainless steel layer 5 and the carbon fiber layer 4, are tightly bonded, thereby improving the structural strength and processing quality of the composite shell.

[0034] In this embodiment, the step S300 of placing the composite tube blank 11 in a vacuum temperature-controlled environment for curing, and the step S503 of placing the composite plate blank 2 in a vacuum temperature-controlled environment for curing both include: Step S301, placing the composite tube blank 11 or the composite plate blank 2 into an autoclave; Step S302, evacuate the autoclave to a pressure value of -0.90 MPa to -1.00 MPa; wherein the pressure value in the autoclave may be -0.90 MPa, -0.93 MPa, -0.95 MPa, -0.96 MPa, -1.00 MPa, etc. The pressure value in the autoclave is not limited to the conditions listed in this embodiment, as long as the autoclave is in a vacuum state during operation. Preferably, the pressure value of the autoclave is -0.95 MPa.

[0035] Step S303, maintain a heating rate of 0.8°C / min~1.2°C / min to raise the temperature in the autoclave to 80°C~90°C, and keep it warm for 25min~35min to complete the heating pre-curing of the composite tube blank 11 or the composite slab blank 2; wherein the heating rate can be 0.8°C / min, 0.9°C / min, 1.0°C / min, 1.2°C / min, etc., the temperature in the autoclave can be 80°C, 82°C, 85°C, 90°C, etc., and the holding time is 25min, 27min, 30min, 35min, etc., and the heating rate, temperature and holding time of the autoclave are not limited to the cases listed in this embodiment. Preferably, when the temperature of the autoclave is raised to 85°C at a heating rate of 1°C / min, the holding time is 30min to complete the pre-curing of the composite tube blank 11 or the composite slab blank 2.

[0036] Step S304, continue to maintain the heating rate of 0.8℃ / min~1.2℃ / min, so that the pressure value in the autoclave reaches 0.45MPa~0.55MPa, and when the temperature is raised to 120℃~130℃, keep the temperature and pressure for 85min~95min to complete the insulation and pressure of the composite tube blank 11 or the composite slab blank 2. Fully solidify; wherein the heating rate can be 0.8℃ / min, 0.9℃ / min, 1.0℃ / min, 1.2℃ / min, etc., the pressure value in the autoclave can be 0.45MPa, 0.50MPa, 0.55MPa, etc., and the pressure value in the autoclave can be The temperature can be 120°C, 125°C, 127°C, 130°C, etc., and the insulation and pressure holding time can be 85min, 87min, 90min, 95min, etc. The heating rate, temperature, pressure value and insulation and pressure holding time of the autoclave are not limited to the cases listed in this embodiment. Preferably, after the pre-curing is completed, the pressure value in the autoclave reaches 0.5MPa, and the heating rate is kept unchanged. That is, when the temperature in the autoclave is increased to 125°C at a heating rate of 1°C / min, the insulation and pressure holding time is 90min to complete the full curing of the composite tube blank 11 or the composite slab blank 2.

[0037] Step S305, the pressure value in the autoclave is reduced to normal atmospheric pressure, and the temperature is reduced to 35°C~45°C, and the composite tube blank 11 or the composite slab blank 2 is cooled and pressurized to be cured to obtain a composite tube 1 or a composite plate. The temperature of the autoclave can be 35°C, 38°C, 40°C, 45°C, etc. The cooling of the autoclave is not limited to the conditions listed in this embodiment. Preferably, the fully solidified composite slab blank 2 or composite tube blank 11 is cooled and pressurized until the pressure value in the autoclave is reduced to normal atmospheric pressure, and the temperature in the autoclave is reduced to 40°C, and then the composite slab blank 2 or composite tube blank 11 is taken out.

[0038] Through the above steps, the aluminum alloy layer 3 and the carbon fiber layer 4 of the composite slab 2 or the composite tube 11 can be tightly bonded through the first adhesive film layer, and the stainless steel layer 5 and the carbon fiber layer 4 can be tightly bonded through the second adhesive film layer, thereby ensuring the structural stability and reliability of the aluminum alloy layer 3, the carbon fiber layer 4 and the stainless steel layer 5 formed by the composite slab 2 or the composite tube 11.

[0039] like Figure 7-Figure 11 As shown, in this embodiment, the heating of the composite tube blank 11 in step S200, and placing the inner die 7 in the composite tube blank 11, pushing the inner die 7 to drive the composite tube blank 11 to pass through the annular die cavity formed by the inner die 7 and the outer die 8 to extrude the composite tube blank 11 in the radial direction, include: Step S201, placing the composite tube blank 11 into the annular mold cavity of the mold consisting of the inner mold 7 and the outer mold 8; Step S202, heating the composite tube blank 11 to a target extrusion temperature of 350°C to 450°C by means of the electromagnetic induction coil 81 disposed in the outer die 8; when working, the electromagnetic induction coil 81 is energized, and the alternating current flowing through the electromagnetic induction coil 81 generates an alternating magnetic field passing through the stainless steel layer 5, and the alternating magnetic field generates eddy currents inside the stainless steel layer 5, so that the purpose of heating the stainless steel layer 5 to the target extrusion temperature is achieved by adjusting the frequency of the electromagnetic induction coil 81, wherein the target extrusion temperature may be 350°C, 400°C, 420°C, 450°C, etc. Preferably, the stainless steel layer 5 of the outer layer of the composite tube blank 11 is heated to a target extrusion temperature of 400°C by means of the electromagnetic induction coil 81 in the outer die 8, so that the metal fluidity of the stainless steel layer 5 matches the metal fluidity of the aluminum alloy layer 3, so that the extrusion forming of the composite tube blank 11 is conveniently processed, and the problems of inharmonious deformation of the composite tube blank 11 during the extrusion process are avoided.

[0040] Step S203, fix the outer die 8 through the extruder 91, and push one end of the inner die 7 to move axially along the composite tube blank 11 through the pressure head 92, so that the composite tube blank 11 is extruded from the extrusion end of the annular die cavity, and the extrusion end is used to apply radial pressure to the composite tube blank 11.

[0041] In some embodiments, the carbon fiber layer 4 is formed by alternately laying multiple layers of carbon fiber woven cloth at angles of 0° and 90°. By alternately laying 0° and 90° layers, the advantages of laying layers at different angles are fully utilized, and the layers at different angles can support each other, so that the carbon fiber layer 4 formed by the multiple layers of carbon fiber woven cloth has good mechanical properties in all directions, reduces the phenomenon of stress concentration, can balance the tensile and shear strengths, and improves the fatigue life of the carbon fiber layer 4, thereby extending the service life of the composite shell.

[0042] At the same time, the present invention also provides a preparation tool for a hydraulic actuator housing, which is used for extruding a composite tube blank 11 in the preparation method of the hydraulic actuator housing described in any of the above embodiments, and the preparation tool comprises: an inner die 7, an outer die 8, an extruder 91 and a pressing head 92; Among them, the inner die 7 is a T-shaped structure, the T-shaped structure has a head 71 and a tail 72, the tail 72 of the T-shaped structure is the positioning end of the inner die 7, and the tail 72 of the T-shaped structure is placed in the composite tube blank 11; an electromagnetic induction coil 81 is arranged in the outer die 8, and the electromagnetic induction coil 81 is used to heat the composite tube blank 11, and the inner wall of the outer die 8 has a large diameter section 82, a slope section 83 and a small diameter section 84, and the large diameter section 82 and the small diameter section 84 are transitionally connected by the slope section 83. The large diameter section 82 of the outer die 8 is sleeved with the head 71 of the inner die 7, and an annular mold cavity is formed between the inner wall of the outer die 8 and the tail 72 of the inner die 7, and the annular mold cavity is used to place the composite tube blank 11, and one end of the annular mold cavity close to the small diameter section 84 has an extrusion end; the extruder 91 is used to clamp and fix the outer wall of the outer die 8; the pressure head 92 is used to push the head 71 of the inner die 7 to extrude the composite tube blank 11 and move along the axis of the composite tube blank 11 toward the extrusion end.

[0043] During operation, the preparation method in step 201, step 202 and step 203 is adopted, and the operator controls the ram 92 to extrude and push the head 71 of the inner die 7, so that the other end surface of the head 71 of the inner die 7 abuts against the end of the composite tube blank 11, and at the same time, the extruder 91 is pressed against the outer wall of the outer die 8, so that the outer die 8 will not be deformed in the radial direction of the outer die 8 during the movement of the inner die 7 along the axis of the composite tube blank 11 toward the small diameter section 84, that is, the stability and reliability of the shape and structure of the annular die cavity formed between the inner wall of the outer die 8 and the tail 72 of the inner die 7 are ensured. As the ram 92 is continuously pushed, the outer wall of the composite tube blank 11 is deformed in the annular direction in sequence. The large diameter section 82, the slope section 83 and the small diameter section 84 of the outer mold 8 pass through the mold cavity. During this process, the electromagnetic induction coil 81 inside the outer mold 8 is connected to a power source, and the alternating current flowing through the electromagnetic induction coil 81 generates an alternating magnetic field passing through the stainless steel layer 5. The alternating magnetic field causes eddy currents to be generated inside the stainless steel layer 5, so that the stainless steel layer 5 is heated by adjusting the frequency of the electromagnetic induction coil 81 to meet the demand for separate temperature control of the stainless steel layer 5 due to the target deformation temperature being too high, while reducing the deformation resistance of the stainless steel layer 5, ensuring that the carbon fiber layer 4 will not solidify prematurely, greatly reducing energy consumption and damage to the extrusion equipment. Specifically, the operator can adjust the frequency of the electromagnetic induction coil 81 according to the extrusion speed of the pressure head 92, so that the stainless steel layer 5 of the composite tube blank 11 is heated due to the eddy current generated inside. Of course, the operator can also adjust the frequency to change the heating depth of the stainless steel layer 5 to ensure that the surface temperature of the stainless steel layer 5 of the composite tube blank 11 can reach the target extrusion temperature of 350°C~450°C during the extrusion process before extrusion forming, which facilitates the processing operation of the composite tube blank 11 and improves the processing efficiency of the composite tube 1.

[0044] like Figure 8 and Fig. 9 As shown, specifically, in the preparation tooling of the hydraulic actuator housing, a water circulation component 73 is also included. The water circulation component 73 is spirally wound and arranged in the inner mold. The water circulation component 73 is used to cool the inner mold 7.

[0045] During operation, water is introduced into the water circulation component 73 through the water inlet 731, and is coiled in the inner mold 8 and located near the outer wall area of ​​the inner mold 7, so that the water in the water circulation component 73 absorbs heat through the outer wall of the inner mold 7 for heat conduction to quickly take away the heat generated during the heating and extrusion forming of the composite tube blank 11. After absorbing the heat, the water flows out from the water outlet 732. During this process, the water circulation component 73 continuously introduces and flows out water to achieve heat dissipation of the composite tube blank 11, avoiding premature curing caused by excessive temperature rise of the carbon fiber layer 4, and improving the production efficiency and production quality of the composite tube 1.

[0046] like Figure 7As shown, specifically, in the preparation tooling of the hydraulic actuator housing, a graphite gasket 93 is also included, and the graphite gasket 93 is arranged between the pressure head 92 and the head 71 of the inner mold 7. The graphite gasket 93 has high temperature resistance, corrosion resistance, thermal conductivity, and good shock resistance and impact resistance, so that when the pressure head 92 pushes the inner mold 7 to move and extrude in the outer mold 8, the pressure head 92 can timely conduct the heat at the inner mold 7 through the graphite gasket 93, avoiding the risk of structural deformation of the preparation tooling due to thermal expansion during operation.

[0047] like Fig.10 and Fig.11 As shown, the outer mold 8 also includes an insulating strip 86, a plurality of insulating rings 85, a fastening screw 87 and an outer mold end cover 88. The plurality of insulating rings 85 are arranged at intervals. The insulating strip 86 connects and fixes the plurality of insulating rings 85 along the arrangement direction to form an insulating frame. The insulating frame is embedded in the outer mold 8. The insulating frame is used to avoid direct contact with the metal at the inner wall of the outer mold 8 for electrical conduction. The outer mold end cover 88 is used to cover the internal structure of the outer mold 8 and is fixed by the fastening screw 87. During operation, the electromagnetic induction coil 81 and the insulating frame are both embedded in the outer mold 8, and then the internal structure of the outer mold 8 is closed by the outer mold end cover 88. The outer mold end cover 88 is fixed by the fastening screw 87, which is convenient for installation and disassembly, and improves the flexibility of the outer mold 8. At the same time, the inner insulating frame and the electromagnetic induction coil 81 are protected and supported by the shell structure of the outer mold 8, so as to avoid extrusion damage to the insulating frame and the electromagnetic induction coil 81 during the forming process, and extend the service life of the outer mold 8.

[0048] Meanwhile, the present invention also provides a hydraulic actuator housing, comprising: a composite pipe 1, a composite flange 21 and a composite end cover 22; Among them, one composite flange 21 is welded to one end of the composite pipe 1, and the other composite flange 21 is welded to the other end of the composite pipe 1; the composite end cover 22 is connected to the composite flange 21 one by one by bolts, and the composite end cover 22 and the composite pipe 1 form a closed space. The composite pipe 1, the composite flange 21 and the composite end cover 22 all have a stainless steel layer 5, a carbon fiber layer 4 and an aluminum alloy layer 3 arranged from the outside to the inside.

[0049] Specifically, in the hydraulic actuator housing, the carbon fiber layer 4 includes CFRP composite material prepreg or GFRP composite material prepreg. Among them, CFRP (Carbon Fiber Reinforced Polymer / Plastic) is an inorganic high-performance fiber with a carbon content of more than 90% that is converted from organic fiber through a series of heat treatments. It is a new material with excellent mechanical properties, has the inherent characteristics of carbon materials, and has the softness and processability of textile fibers. It is a new generation of reinforcing fibers; GFRP (Glass Fiber Reinforced Plastics) is a composite plastic with glass fiber reinforced unsaturated polyester, epoxy resin and phenolic resin as matrix materials. Both CFRP composite material prepreg and GFRP composite material prepreg have high strength, good corrosion resistance and fatigue resistance, and are suitable for the design of various complex structures and shapes, and are easy to process. The carbon fiber layer 4 can also use other composite materials. The material of the carbon fiber layer 4 is not limited to the case listed in this embodiment, as long as the carbon fiber layer 4 has high strength and can achieve stacking and curing.

[0050] Specifically, the hydraulic actuator housing also includes a sealing component 23, which is arranged between the composite flange 21 and the composite end cover 22. The sealing component 23 may be a foot pad, a sealing ring or other structures with a sealing function, and the sealing component 23 is not limited to the cases listed in this embodiment. By arranging the sealing component 23 between the composite flange 21 and the composite end cover 22, the sealing effect of the closed space formed by the composite pipe 1, the composite flange 21 and the composite end cover 22 is ensured, and at the same time, the wear between the composite flange 21 and the composite end cover 22 during the assembly process is reduced by the sealing ring, thereby extending the service life of the hydraulic actuator housing.

[0051] 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.

[0052] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for preparing a hydraulic actuator housing, characterized in that: For preparing a closed shell having a composite pipe, a composite flange and a composite end cover, the preparation method comprises: A composite tube blank is provided, wherein the composite tube blank comprises, from inside to outside, an aluminum alloy layer, a first adhesive film layer, a carbon fiber layer, a second adhesive film layer and a stainless steel layer; The composite tube blank is heated, and an inner die is placed in the composite tube blank, and the inner die is pushed to drive the composite tube blank to pass through the annular die cavity formed by the inner die and the outer die to extrude the composite tube blank in the radial direction, so that the aluminum alloy layer, the carbon fiber layer and the stainless steel layer are tightly combined; Placing the composite tube blank in a vacuum temperature-controlled environment for curing to obtain the composite tube; The two ends of the composite pipe are respectively connected to one of the composite flanges, and the side of each composite flange away from the composite pipe is connected to one of the composite end covers to obtain a composite shell.

2. The method for preparing a hydraulic actuator housing according to claim 1, characterized in that: The preparation method of the composite flange and the composite end cover comprises: Providing a composite slab, the composite slab comprising, from bottom to top, the aluminum alloy layer, the first adhesive film layer, the carbon fiber layer, the second adhesive film layer and the stainless steel layer; Performing a vacuum treatment on the composite slab by using a vacuum device; Placing the composite slab in a vacuum temperature-controlled environment for curing to obtain a composite plate; The composite plate is cut to obtain the composite flange and the composite end cap.

3. The method for preparing a hydraulic actuator housing according to claim 2, characterized in that: The vacuum device comprises a template, a demoulding cloth, an isolation film, a vacuum nozzle, a vacuum bag, a vacuum pump, a breathable felt and a high temperature resistant rubber strip; The vacuuming treatment of the composite slab by a vacuum device comprises: spraying a release agent on the template; The demoulding cloth, the composite slab, the isolation film, the breathable felt and the vacuum bag are sequentially stacked on the template, and the breathable felt is also arranged around the side of the composite slab, the composite slab is isolated from the vacuum bag by the isolation film and the breathable felt, the vacuum bag and the template are sealed and connected by the high temperature resistant rubber strip to form a working cavity, and the working cavity is connected to the vacuum pump through the vacuum nozzle; The working chamber is evacuated by the vacuum pump.

4. The method for preparing a hydraulic actuator housing according to claim 2, characterized in that: The step of curing the composite tube blank in a vacuum temperature-controlled environment and the step of curing the composite slab blank in a vacuum temperature-controlled environment both include: Putting the composite tube blank or the composite plate blank into an autoclave; The autoclave is evacuated to a pressure of -0.90 MPa to -1.00 MPa; Maintaining a heating rate of 0.8°C / min to 1.2°C / min to raise the temperature in the autoclave to 80°C to 90°C, and then maintaining the temperature for 25min to 35min to complete the heating pre-curing of the composite tube blank or the composite slab blank; Continue to maintain a heating rate of 0.8°C / min to 1.2°C / min, so that the pressure value in the autoclave reaches 0.45MPa to 0.55MPa, and when the temperature rises to 120°C to 130°C, keep the temperature and pressure for 85min to 95min to complete the heat preservation and pressure maintenance of the composite tube blank or the composite slab to fully solidify; The pressure value in the autoclave is reduced to normal atmospheric pressure, and the temperature is reduced to 35° C. to 45° C., so as to complete the temperature reduction and pressure reduction solidification of the composite tube blank or the composite plate blank to obtain the composite tube or the composite plate.

5. The method for preparing a hydraulic actuator housing according to claim 1, characterized in that: The step of heating the composite tube blank, placing an inner die in the composite tube blank, pushing the inner die to drive the composite tube blank through the annular die cavity formed by the inner die and the outer die to extrude the composite tube blank in the radial direction comprises: Placing the composite tube blank into an annular mold cavity of a mold consisting of an inner mold and an outer mold; The composite tube blank is heated to a target extrusion temperature of 350° C. to 450° C. by an electronic induction coil disposed in the outer die; The outer die is fixed by an extruder, and one end of the inner die is pushed by a pressure head to move along the axial direction of the composite tube blank, so that the composite tube blank is extruded from the extrusion end of the annular die cavity, and the extrusion end is used to apply radial pressure to the composite tube blank.

6. The method for preparing a hydraulic actuator housing according to any one of claims 1 to 5, characterized in that: The carbon fiber layer is formed by laying multiple layers of carbon fiber woven cloth alternately at angles of 0° and 90°.

7. A tooling for preparing a hydraulic actuator housing, characterized in that: For extruding the composite tube blank in the method for preparing the hydraulic actuator housing according to any one of claims 1 to 6, the preparation tool comprises: An inner mold, wherein the inner mold is a T-shaped structure, the T-shaped structure has a head and a tail, the tail of the T-shaped structure is a positioning end of the inner mold, and the tail of the T-shaped structure is placed in the composite tube blank; An outer mold, wherein an electromagnetic induction coil is arranged inside the outer mold, and the electromagnetic induction coil is used to heat the composite tube blank. The inner wall of the outer mold has a large diameter section, a slope section and a small diameter section, and the large diameter section and the small diameter section are transitionally connected by the slope section. The large diameter section of the outer mold is sleeved with the head of the inner mold, and the annular mold cavity is formed between the inner wall of the outer mold and the tail of the inner mold. The annular mold cavity is used to place the composite tube blank, and one end of the annular mold cavity close to the small diameter section has an extrusion end; An extruder, used for clamping and fixing the outer wall of the outer mold; The pressure head is used to push the head of the inner die to extrude the composite tube blank and move it along the axis of the composite tube blank toward the extrusion end.

8. The tooling for preparing the hydraulic actuator housing according to claim 7, characterized in that: It also includes a water circulation component, which is spirally wound and arranged in the inner mold, and is used to cool the inner mold.

9. A hydraulic actuator housing, characterized in that: include: Composite pipe; Two composite flanges, one of which is welded to one end of the composite pipe, and the other composite flange is welded to the other end of the composite pipe; Two composite end covers, the composite end covers are connected to the composite flanges in a one-to-one correspondence through bolts, the composite end covers and the composite pipes enclose a closed space, and the composite pipes, the composite flanges and the composite end covers all have a stainless steel layer, a carbon fiber layer and an aluminum alloy layer arranged from outside to inside.

10. The hydraulic actuator housing according to claim 9, characterized in that: The carbon fiber layer includes CFRP composite material prepreg or GFRP composite material prepreg.

Images