Polyether-ether-ketone pipeline induction welding structure and connection process method
Through the induction welding technology of embedded metal rings, the problems of insufficient adaptability and low welding quality of PEEK composite pipeline joint joints are solved, and high-strength and highly adaptable pipeline connections are achieved.
Patent Information
- Application Number
- CN202510315227.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-17
- Publication Date
- 2025-06-13
AI Technical Summary
In the prior art, the PEEK composite pipeline joint connections have problems such as insufficient adaptability, difficulty in ensuring the joint dimensional accuracy, and traditional contact welding easily damages the pipeline surface and uneven heat distribution.
The induction welding structure with an embedded metal ring is adopted, and the metal ring is heated by electromagnetic induction to melt and soak the PEEK resin into the circular hole of the metal ring, achieving high-strength connection between the joint and the tube.
High-strength connection of any specification pipeline is achieved, the bonding strength is higher than that of secondary injection molding, the pressure is higher, the steps are reduced, the time is shortened, and the production efficiency is improved.
Smart Images
Figure CN120134647A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of pipeline connection, and particularly relates to a polyetheretherketone pipeline induction welding structure and a connection process method. Background Art
[0002] With the increasing demand for lightweight pipelines in aircraft, PEEK (polyetheretherketone) composite pipelines, as a kind of high-performance composite pipelines, are gradually used in the water / wastewater, anti / ice removal, and liquid cooling systems in the aviation field. The connection of PEEK composite pipeline joints is the key factor restricting their application. At present, small-diameter pipelines mainly use flared threaded connections, and large-diameter pipelines use the form of secondary injection-molded joints for connection under low-pressure and negative-pressure working conditions. As a thermoplastic engineering plastic, PEEK material can be melted and re-consolidated multiple times. Induction welding can accurately heat the welding part of the pipeline through electromagnetic induction, effectively avoiding mechanical damage to the pipeline surface, and improving the welding efficiency and quality stability. It is one of the most promising welding technologies.
[0003] The disadvantages of the connection of PEEK composite pipeline joints in the prior art are summarized as follows:
[0004] 1. The flared threaded connection is only applicable to small-diameter pipelines, and there is no suitable nut for connecting large-diameter pipelines, so its application is limited.
[0005] 2. The form of the secondary injection-molded joint has requirements for the external dimensions of the pipeline, and there are situations where the pressure resistance is low and the dimensional accuracy of the joint cannot be guaranteed, so it cannot be used for liquid cooling systems connected by flexible clamps and quick-release clamps.
[0006] 3. Connecting the pipeline through traditional contact welding is likely to cause damage to the pipeline surface, and the heat distribution is uneven, affecting the welding quality. Summary of the Invention
[0007] To solve the technical problem of difficult connection of PEEK composite pipeline joints, the present invention provides a polyetheretherketone pipeline induction welding structure and a connection process method.
[0008] The object of the present invention is achieved by adopting the following technical solutions. A polyetheretherketone pipeline induction welding structure according to the present invention includes a joint. The joint includes a welding end for connecting with a pipe. Inside the welding end of the joint, there is a welding cavity for accommodating the pipe. The outer wall of the welding end of the pipe contacts the inner wall surface of the welding cavity. A metal ring is nested on the inner wall of the welding cavity. Multiple circular hole groups are distributed along the axial direction on the side wall of the metal ring. Each circular hole group includes multiple circular holes distributed circumferentially. The circular holes of adjacent circular hole groups are staggered in the axial direction.
[0009] Further, the inner wall of the metal ring is flush with the inner wall of the welding cavity.
[0010] Further, one end face of the metal ring is flush with the welding end face of the joint.
[0011] Further, a stop step is provided on the inner wall of the joint. After the pipe is inserted into the joint, it abuts against the stop step so that the welding end of the pipe is located inside the metal ring.
[0012] Further, the other end of the joint is a connection end for connecting to a device or pipeline. The inside of the connection end is a connection cavity, and the connection cavity communicates with the welding cavity.
[0013] Further, the joint is a joint made of polyether ether ketone material, and the pipe is a pipe made of polyether ether ketone material.
[0014] Further, the round holes are evenly distributed on the metal ring.
[0015] A polyether ether ketone pipeline connection process method includes the following steps:
[0016] The joint and the metal ring are formed by injection molding. After injection molding, the metal ring is nested on the inner wall of the joint;
[0017] The joint after injection molding is machined to ensure that the interface dimension accuracy of the joint meets the design requirements;
[0018] The pipe is inserted into the welding cavity of the joint, and the outer wall of the welding end of the pipe contacts the inner wall surface of the metal ring;
[0019] The joint and the pipe are axially positioned. Ring-shaped devices are provided on the outer wall of the welding end of the joint and the inner wall of the welding end of the pipe to apply pressure from the outside to the inside to the outer wall of the welding end of the joint and pressure from the inside to the outside to the inner wall of the welding end of the pipe;
[0020] The metal ring is heated by electromagnetic induction to melt the PEEK resin on the joint and the pipe and infiltrate it into the round holes of the metal ring. After the PEEK resin solidifies, the connection between the joint and the pipe is realized.
[0021] Further, during injection molding, the metal ring is pre-fixed as an insert into the molding die of the joint. The fixing position of the metal ring corresponds to the welding end position of the joint and is located on the inner wall of the joint after injection molding. The thermoplastic injection machine is debugged and the process parameters are set. After injection molding in one body, the outer end face of the metal ring is flush with the welding end face of the joint blank.
[0022] Further, before welding the joint and the pipe, counterweights are respectively pressed on the joint and the pipe, and the counterweights are respectively placed inside the non-welding ends of the joint and the pipe to prevent axial displacement of the joint and the pipe. An outer hoop retaining ring is sleeved on the outer wall of the welding end of the joint, and an inner expansion sleeve is nested in the inner hole of the welding end of the pipe, so that when welding, an outward-inward pressure is applied to the outer circumference at the welding position, and an inward-outward pressure is applied to the inner circumference at the welding position to tighten the inner hole wall.
[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0024] When the joint with the embedded metal ring is welded to the pipe, the PEEK resin can fully penetrate into the reticulated metal ring, and the pipe and the joint are effectively anchored, realizing a high-strength connection between the joint and the pipe. The joint can be realized by injection molding and is applicable to any specification of joint form. The inner wall of the joint is embedded with a reticulated metal ring and injection molded. The joint and the pipe are welded by induction heating, and the bonding strength is higher than that of secondary injection molding and can withstand higher pressure. Compared with secondary injection molding, the present invention has fewer steps, shorter time, higher production efficiency, and stronger adaptability to the pipeline structure and size.
[0025] The above description is only an overview of the technical solution of the present invention. In order to understand the technical means of the present invention more clearly, it can be implemented according to the content of the specification. In order to make the purpose, features and advantages of the present invention more obvious and understandable, the following preferred embodiments are specifically given and described in detail in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 It is a sectional perspective view of the joint in the embodiment of the induction welding structure of a polyetheretherketone pipeline of the present invention;
[0027] Figure 2 It is a half-sectional view of the joint in the embodiment of the induction welding structure of a polyetheretherketone pipeline of the present invention;
[0028] Figure 3 is Figure 1 , Figure 2 a three-dimensional schematic diagram of the metal ring in
[0029] Figure 4 is Figure 3 a side view of
[0030] Figure 5 is Figure 1 , Figure 2 a connection schematic diagram of the joint and the pipe in
[0031] Figure 6 It is a schematic diagram of both ends of the pipe being connected to the joint in the embodiment of the induction welding structure of a polyetheretherketone pipeline of the present invention.
[0032] Reference numerals:
[0033] 1 - Metal ring,
[0034] 101 - Round hole,
[0035] 2 - Connector,
[0036] 201 - Stopping step,
[0037] 202 - Welding cavity,
[0038] 203 - Connecting cavity,
[0039] 3 - Pipe. Detailed implementation manners
[0040] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some but not all of the embodiments of the present application. Usually, the components of the embodiments of the present application described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.
[0041] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application claimed, but merely represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.
[0042] It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.
[0043] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this application is usually placed when in use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance.
[0044] In addition, the terms "horizontal", "vertical", "hanging", etc. do not mean that the components are required to be absolutely horizontal or hanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.
[0045] In the description of the present application, it should also be noted that unless otherwise clearly specified and defined, the terms "arranged", "installed", "connected", and "joined" 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.
[0046] In the present application, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than that of the second feature.
[0047] The features and performance of a polyetheretherketone pipeline induction welding structure and a connection process method suitable for the present application are further described in detail below in conjunction with embodiments.
[0048] An embodiment of a polyetheretherketone pipeline induction welding structure of the present invention is as Figures 1 to 6 shown. The induction welding structure includes a joint 2 and a pipe 3. Both the joint 2 and the pipe 3 are made of PEEK (polyetheretherketone) material, and can also be made of other composite materials that melt after heating and solidify after cooling.
[0049] A net-like metal ring 1 is embedded in the inner wall of the joint 2. The metal ring 1 is in the shape of a circular tube as a whole. The side wall of the metal ring 1 is provided with staggered round holes 101. Specifically, multiple groups of round holes are axially distributed on the side wall of the metal ring 1. Each group of round holes is circumferentially distributed with multiple round holes 101 on the metal ring 1. The round holes 101 of adjacent groups of round holes are axially staggered from each other. When the pipe 3 is inserted into the joint 2, it is also inserted into the metal ring 1. The metal ring 1 is heated by induction heating to melt the PEEK materials at the welding ends of the pipe 3 and the joint 2. The melted PEEK materials flow into the round holes 101. Since the round holes 101 are axially staggered from each other, the PEEK materials flowing into the round holes 101 are also axially staggered. The gaps between the inner wall of the joint 2, the inner wall of the metal ring 1 and the outer wall of the pipe 3 are filled with axially staggered PEEK materials. The liquid in the pipeline flows axially, which can enhance the sealing effect. Therefore, through the axially staggered round holes 101, better sealing effect can be achieved after the joint 2 and the corresponding pipe 3 are welded. After the pipe 3 is inserted into the joint 2 and welded and fixed, the axial connection between the pipe 3 and the joint 2 is relatively fragile. By infiltrating the PEEK resin through the axially staggered round holes 101, the axial tensile strength can be increased to ensure the firm connection between the pipe 3 and the joint 2.
[0050] The round holes 101 on the metal ring 1 are evenly distributed. After the PEEK resin is fully melted, it is evenly distributed into each round hole 101, which can effectively disperse stress, reduce local stress concentration and make the bonding strength higher. When the pipe 3 is inserted into the joint 2, the pipe 3 is also inserted into the metal ring 1. The metal ring 1 is heated by induction welding to make the metal ring 1 heat up and melt the joint 2 and the pipe 3. The melted joint 2 and pipe 3 are embedded into the round holes 101 and solidify. Both the joint 2 and the pipe 3 achieve the anchoring effect with the metal ring 1, thus realizing the effective connection between the joint 2 and the pipe 3.
[0051] One end of the joint 2 is a welding end for welding connection with the pipe 3, and the other end is a connection end for connection with other pipelines or devices. The inside of the welding end of the joint 2 is a welding cavity 202, and the inside of the connection end is a connection cavity 203. The welding cavity 202 is communicated with the connection cavity 203. A stop step 201 is arranged on the inner wall of the joint 2. The stop step 201 is used to separate the welding cavity 202 and the connection cavity 203. And the inner diameter of the welding cavity 202 is larger than that of the connection cavity 203. The metal ring 1 is nested on the inner wall of the welding cavity 203, and the inner wall of the metal ring 1 is flush with the inner wall of the welding cavity 203. The pipe 3 is inserted into the welding cavity 202 and abutted against the stop step 201 to realize the positioning of the pipe 3. At this time, the inserted end of the pipe 3 is just located inside the metal ring 1. During induction welding, the heat generated by the metal ring 1 can melt the inserted end of the pipe 3 and the inner wall of the welding cavity 202, so that the pipe 3 and the joint 2 are firmly combined through the metal ring 1.
[0052] The fixing method of the joint 2 and the metal ring 1 is as follows: The joint 2 is formed by injection molding. The metal ring 1 is pre-fixed into the molding die of the joint 2 as an insert. The fixing position corresponds to the welding end position of the joint 2. The thermoplastic injection machine is debugged and the preferred process parameters are set. After injection molding in one piece, the outer end face of the metal ring 1 is flush with the welding end face of the blank of the joint 2. And the interface dimension accuracy of the joint 2 is ensured by supplementary machining. After machining, the outer end face of the metal ring 1 is flush with the welding end face of the joint 2.
[0053] After the joint 2 is injection molded and fixed to the metal ring 1, the tube 3 is inserted into the joint 2 and positioned by the stop step 201. The outer wall of the tube 3 contacts the inner wall of the metal ring 1. The metal ring 1 is heated by electromagnetic induction, so that the PEEK resin in contact with the metal ring 1 is heated and melted and fully infiltrates into the round hole 101 of the metal ring. The tube 3 is coaxially docked with the joint 2. The outer diameter of the tube 3 is the same as the inner diameter of the joint 2 and the tube 3 can be inserted into the joint 2. After the tube 3 is inserted into the joint 2, a surface contact is formed, so that the tube 3 can be in full contact with the metal ring 1. Before welding, counterweights are respectively pressed on the joint 2 and the tube 3. The counterweights can be respectively placed inside the non-welding ends of the joint 2 and the tube 3 to prevent the joint 2 and the tube 3 from having axial displacement during the heating and welding process and keep the positions of the joint 2 and the tube 3 unchanged. Before welding, an outer hoop retaining ring is sleeved on the outer wall of the joint 2 (the overlapping section of the tube 3 and the joint 2) at the welding position, and an inner expansion sleeve is nested in the inner hole of the tube 3 (the overlapping section of the tube 3 and the joint 2) at the welding position. An inward pressure from outside to inside is applied to the outer circumference at the welding position through the outer hoop retaining ring, and an outward pressure from inside to outside is applied to the inner circumference at the welding position through the inner expansion sleeve to tighten the inner hole wall, which can keep the circumferential shape at the welding position during the welding process, compact the melted PEEK resin material, fill the gap between the joint 2 and the tube 3, enhance the welding effect and increase the connection strength between the tube 3 and the joint 2. During the welding process, parameters such as welding pressure (the pressure applied by the inner expansion sleeve and the outer hoop retaining ring), welding current and welding time are strictly controlled, and auxiliary tools such as the inner expansion sleeve, the outer hoop retaining ring and the counterweights are used to achieve a high-strength connection between the joint 2 and the tube 3. In this embodiment, the outer hoop retaining ring can be a clamp tightened by bolts. The clamp is clamped at the welding position, and the bolts are gradually tightened during welding to apply pressure to the joint 2. The inner expansion sleeve can be an expansion sleeve. Before welding, the expansion sleeve is inserted into the tube 3, and during welding, the expansion sleeve is operated to expand outward and press against the inner wall of the tube 3.
[0054] As Figure 5 shown is a schematic diagram after the joint 2 and the tube 3 are connected. The tube 3 can be connected to the corresponding pipeline or device through the joint 2. It is also possible to weld the joint 2 at both ends of the tube 3. As Figure 6 shown, the pipelines or devices on both sides of the tube 3 can be connected through the joints 2 at both ends of the tube 3.
[0055] Preferably, the inner diameter of the mesh metal ring 1 is 57 mm, the thickness is 1.4 mm, the width is 20 mm, the diameter of the round hole is 2 mm, the inner diameter of the welding end of the joint 2 is 57 mm, and the wall thickness is 1.5 mm. When the metal ring 1 and the joint 2 are integrally injection-molded, the nozzle temperature at the discharge port of the thermoplastic injection molding machine is 405 °C, the injection pressure is 150 bar, the injection speed is 80 mm / s, the holding pressure is 80 bar, the holding time is 8 s, the cooling time is 200 s, and the mold temperature is 195 °C. The outer diameter of the pipe 3 is 57 mm and the wall thickness is 1.5 mm. When the pipe 3 and the joint 2 are induction welded, a knob-type power-adjustable electromagnetic heating device is used. The welding power is about 0.3 kW, the welding duration is about 65 s, and the welding pressure is about 6 kg. The welding pressure can be achieved by means of an internal expansion sleeve, an external hoop retaining ring, and a counterweight.
[0056] The joint 2 with the embedded metal ring 1 and the pipe 3 are welded, and the PEEK resin can fully penetrate into the mesh metal ring 1, and the pipe 3 and the joint 2 are effectively anchored, realizing a high-strength connection between the joint 2 and the pipe 3. The joint 2 can be realized by injection molding and is suitable for any specification of the joint form. The inner wall of the joint 2 is embedded with the mesh metal ring 1 and injection-molded. The joint 2 and the pipe 3 are induction-heated and welded, and the bonding strength is higher than that of secondary injection molding, and the pressure resistance is higher. Compared with secondary injection molding, the present invention has fewer steps, shorter time, higher production efficiency, and stronger adaptability to the pipeline structure and size.
[0057] In other embodiments of a polyetheretherketone pipeline induction welding structure, on the basis of the above embodiments, the metal ring 1 can be completely located within the wall body of the joint 2. When the metal ring 1 is heated, the wall body of the joint 2 and the wall body of the insertion end of the pipe 3 are melted and solidified into one body.
[0058] In other embodiments of a polyetheretherketone pipeline induction welding structure, on the basis of the above embodiments, the metal ring 1 can be arranged on the inner wall of the joint 2 close to the inside, and the outer end face of the metal ring 1 does not have to be flush with the welding end face of the joint 2.
[0059] An embodiment of a polyetheretherketone pipeline connection process method of the present invention includes the following steps:
[0060] (1) The joint 2 and the metal ring 1 are formed by injection molding. After injection molding, the metal ring 1 is nested on the inner wall of the joint 2, forming a joint 2 with the metal ring 1. Specifically, the metal ring 1 is pre-fixed into the molding die of the joint 2 as an insert. The fixed position of the metal ring 1 corresponds to the welding end position of the joint 2 and is located on the inner wall of the joint 2 after injection molding; the thermoplastic injection molding machine is debugged and the preferred process parameters are set. After integral injection molding, the outer end face of the metal ring 1 close to the outside is flush with the welding end face of the blank of the joint 2.
[0061] (2) The joint 2 after injection molding is machined by supplementary machining to ensure that the interface dimension accuracy of the joint 2 meets the design requirements.
[0062] (3) After the joint 2 is machined, the pipe 3 is inserted into the welding cavity 202 of the joint 2 and positioned by the stop step 201, and the outer wall of the welding end of the pipe 3 contacts the inner wall surface of the metal ring 1.
[0063] (4) The joint 2 and the pipe 3 are axially positioned to prevent axial displacement due to external force, and annular devices are provided on the outer wall of the joint 2 and the inner wall of the pipe 3 at the welding position to apply an outward-to-inward pressure to the outer wall of the joint 2 at the welding position and an inward-to-outward pressure to the inner wall of the pipe 3 at the welding position, which can maintain the circumferential shape at the welding position during the subsequent welding process, compact the melted PEEK resin material, fill the gap between the joint 2 and the pipe 3, and enhance the welding effect. Specifically: use counterweights to press on the joint 2 and the pipe 3 respectively, or clamp the joint 2 and the pipe 3 through clamping tools. The counterweights can be placed inside the non-welding ends of the joint 2 and the pipe 3 respectively to avoid axial displacement of the joint 2 and the pipe 3 during the heating welding process and keep the positions of the joint 2 and the pipe 3 unchanged; an outer hoop retaining ring is sleeved on the outer wall of the joint 2 (the overlapping section of the pipe 3 and the joint 2) at the welding position, and an inner expansion sleeve is nested in the inner hole of the pipe 3 (the overlapping section of the pipe 3 and the joint 2) at the welding position, so that during welding, an outward-to-inward pressure is applied to the outer circumference at the welding position and an inward-to-outward pressure is applied to the inner circumference at the welding position to tighten the inner hole wall.
[0064] (5) The metal ring 1 is heated by electromagnetic induction, so that the PEEK resin on the joint 2 and the pipe 3 in contact with the metal ring 1 is heated and melted, and fully infiltrates into the round hole 101 of the metal ring 1. After the PEEK resin solidifies, the connection between the joint 2 and the pipe 3 is realized. During the welding process, parameters such as welding pressure (the pressure applied by the inner expansion sleeve and the outer hoop retaining ring), welding current, and welding time are strictly controlled, and auxiliary tools such as the inner expansion sleeve, the outer hoop retaining ring, and the counterweights are used to achieve a high-strength connection between the joint 2 and the pipe 3.
[0065] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A polyetheretherketone pipeline induction welding structure, comprising a joint (2), characterized in that: The joint (2) comprises a welding end for connecting to a pipe (3); a welding cavity (202) for accommodating the pipe (3) is provided inside the welding end of the joint (2); the outer wall of the welding end of the pipe (3) contacts the inner wall surface of the welding cavity (202); a metal ring (1) is embedded in the inner wall of the welding cavity (202); a plurality of circular hole groups are distributed axially on the side wall of the metal ring (1); each circular hole group comprises a plurality of circular holes (101) distributed circumferentially; and the circular holes (101) of adjacent circular hole groups are staggered in the axial direction.
2. The polyetheretherketone pipeline induction welding structure according to claim 1, characterized in that: The inner wall of the metal ring (1) is flush with the inner wall of the welding cavity (202).
3. The polyetheretherketone pipeline induction welding structure according to claim 1, characterized in that: One end surface of the metal ring (1) is flush with the end surface of the welding end of the joint (2).
4. The polyetheretherketone pipeline induction welding structure according to claim 1, characterized in that: The inner wall of the joint (2) is provided with a stop step (201), and after the pipe (3) is inserted into the joint (2), it abuts against the stop step (201) so that the welding end of the pipe (3) is located inside the metal ring (1).
5. The polyetheretherketone pipeline induction welding structure according to claim 1, characterized in that: The other end of the joint (3) is a connection end for connecting to a device or a pipeline, and the interior of the connection end is a connection cavity (203), and the connection cavity (203) is in communication with the welding cavity (202).
6. The polyetheretherketone pipeline induction welding structure according to claim 1, characterized in that: The joint (2) is a joint (2) made of polyetheretherketone material, and the tube (3) is a tube (3) made of polyetheretherketone material.
7. The polyetheretherketone pipeline induction welding structure according to claim 1, characterized in that: The circular holes (101) are evenly distributed on the metal ring (1).
8. A polyetheretherketone pipeline connection process, characterized in that: The following steps are involved: The joint (2) and the metal ring (1) are formed by injection molding. After the injection molding, the metal ring (1) is nested in the inner wall of the joint (2); The injection-molded joint (2) is machined to ensure that the interface dimension accuracy of the joint (2) meets the design requirements; The tube (3) is inserted into the welding cavity (202) of the joint (2), and the outer wall of the welding end of the tube (3) contacts the inner wall surface of the metal ring (1); The joint (2) and the pipe (3) are positioned in the axial direction, and the outer wall of the welding end of the joint (2) and the inner wall of the welding end of the pipe (3) are both provided with an annular device for applying pressure from the outside to the inside to the outer wall of the welding end of the joint (2) and applying pressure from the inside to the outside to the inner wall of the welding end of the pipe (3); The metal ring (1) is heated by electromagnetic induction, so that the PEEK resin on the joint (2) and the tube (3) is melted by the heat and infiltrates into the circular hole (101) of the metal ring (1). After the PEEK resin solidifies, the connection between the joint (2) and the tube (3) is achieved.
9. A polyetheretherketone pipeline connection process according to claim 8, characterized in that: During injection molding, the metal ring (1) is pre-fixed in the molding die of the joint (2) as an insert. The fixing position of the metal ring (1) corresponds to the position of the welding end of the joint (2) and is located on the inner wall of the joint (2) after injection molding. The thermoplastic injection machine is debugged and the process parameters are set. After integral injection molding, the outer end surface of the metal ring (1) is flush with the welding end surface of the joint (2) blank.
10. A polyetheretherketone pipeline connection process according to claim 8, characterized in that: Before welding the joint (2) and the pipe (3), a counterweight is used to press the joint (2) and the pipe (3) respectively, and the counterweight is placed inside the non-welding ends of the joint (2) and the pipe (3) respectively to prevent the joint (2) and the pipe (3) from axial displacement; an outer hoop retaining ring is sleeved on the outer wall of the welding end of the joint (2), and an inner expansion sleeve is embedded in the inner hole of the welding end of the pipe (3), so that during welding, pressure is applied from the outside to the inside on the outer circumference of the welding position, and pressure is applied from the inside to the outside on the inner circumference of the welding position, so as to tighten the inner hole wall.