PE pipe fitting induction welding joint and induction welding method

Abstract

The PE pipe fitting induction welding joint comprises a joint body, the joint body comprises a connector, a metal layer is arranged on the inner circumferential wall of the connector, the metal layer is of an annular structure and is provided with a channel penetrating through the inner circumference and the outer circumference of the metal layer, the metal layer is of a metal net structure, and the metal layer is of an annular structure. A plurality of through holes are formed in the side wall of the metal layer, an observation hole is formed in the side wall of the connector, one end of the observation hole can be communicated with the metal layer, and the other end of the observation hole is open towards the outer wall of the connector. The materials on the periphery of the net are heated and melted through induction heating, and the materials on the surface in contact with the pipe fitting are melted and then cooled to be welded.

Description

Technical Field

[0001] The present invention relates to the technical field of pipe fittings, and more specifically, to an induction welding joint of a PE pipe fitting, and also to an induction welding method of a PE pipe fitting. Background Art

[0002] When connecting some pipe fittings and joints, electric fusion welding is used to achieve welding. During the production process of electric fusion welding pipe fitting joints, metal conductive wires are preset in the inner layer of the joint, and points for connecting electricity are formed on the outside of the pipe fittings. During the welding process, the power is connected to the conductive wire, which acts as an electric heating wire and can generate heat. The material near the conductive wire will be melted by the heat, thereby achieving welding and fixing of the pipe fitting joint and the pipe.

[0003] The joints of electrofusion welding have high requirements for the wiring and materials of the internal conductive wires. The conductive wires need to be energized to generate heat and achieve electrofusion welding. However, during the production and operation process, problems such as broken wires and short circuits are prone to occur inside the joints of electrofusion welding, resulting in the conductive wires not being able to be energized and heated smoothly, and local heating not being able to occur normally. Local welding leaks are prone to occur during welding, resulting in poor welding.

[0004] Therefore, a new solution needs to be proposed to solve this problem. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide an induction welding joint for PE pipe fittings and an induction welding method, which can realize welding by electromagnetic induction.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A PE pipe induction welding joint comprises a joint body, the joint body comprises an interface, the inner circumferential wall of the interface is provided with a metal layer, the joint body and the metal layer are integrally injection molded, the metal layer is annular in structure, and is provided with a channel penetrating the inner and outer circumferences of the metal layer; a protruding limiting portion is formed on the inner circumference of the interface, and the limiting portion is used to block and position a pipe body inserted into the interface; the side of the metal layer facing the opening of the interface is a first end, and the other end is a second end, a first cooling zone is formed between the first end of the metal layer and the opening of the interface, and a second cooling zone is formed between the second end of the metal layer and the limiting portion.

[0008] The present invention is further configured such that the metal layer is an annular spring-like structure, and the metal layer can elastically expand and contract along the length direction.

[0009] The present invention is further configured such that the metal layer gradually decreases toward the second end, an inner lining layer is formed between the metal layer and the inner circumferential surface of the interface, and the thickness of the inner lining layer gradually decreases toward the second end of the metal layer.

[0010] The present invention is further configured such that the side wall of the interface is provided with two observation holes, namely a first observation hole and a second observation hole, wherein the first observation hole is located at a first end periphery of the metal layer, and the second observation hole is located at a second end periphery of the metal layer.

[0011] The present invention is further configured to further include a support member, the support member is a rod-shaped structure, a portion of the support member is fixedly connected to the first end of the metal layer, and another portion of the support member extends toward the joint body and is pre-buried and fixedly connected to the joint body;

[0012] The present invention is further configured such that the joint body comprises two joints, the two joints are coaxially arranged, the inner walls of the two joints are both provided with the metal layer, and the two ends of the support member are fixedly connected to the two joints on both sides.

[0013] The present invention is further configured such that the metal layer is a metal mesh structure, and a plurality of through holes are formed on the side wall of the metal layer.

[0014] The present invention is further configured such that an observation hole is provided on the side wall of the interface, one end of the observation hole can be connected to the metal layer, and the other end is open toward the outer wall of the interface.

[0015] The present invention also provides an induction welding method for PE pipe fittings, including a pipe body and a PE pipe fitting induction welding joint as described above, wherein the outer diameter of the pipe body and the inner diameter of the interface are mutually adapted; the pipe body is inserted into the interface, and the metal layer in the interface is heated by electromagnetic induction heating, and the materials of the inner layer of the interface and the outer layer of the pipe body are melted after being heated, and after cooling, the joint body and the pipe body are welded and fixed to each other.

[0016] In summary, the present invention has the following beneficial effects:

[0017] By arranging an annular metal layer in the joint, electromagnetic induction can be used to achieve heating. After heating, the materials around it are heated and melted, so that the surface materials in contact with the pipe parts are melted and then bonded together after cooling; by using electromagnetic induction for heating, the layout structure of the metal layer inside the joint can be simplified. Compared with the electric fusion welding joint, the production requirements are lower, the manufacturing cost can be reduced, and the problems of wire breakage and short circuit that are prone to occur in the electric fusion welding joint during the welding process can be overcome, and the problem of water leakage caused by uneven welding and leaking welding during the welding process can be avoided.

[0018] By using a spring as the metal layer, the spring can achieve elastic deformation in the length direction. During the induction welding process, the inserted pipe will cause the spring and the nearby molten material to adhere. The adhesion can cause the spring to deform slightly. After the pipe is fully inserted, the spring will gradually recover elastically, forming a pressure effect, so that the local molten material can gather toward the middle section of the metal layer. The molten material can be gathered to ensure that the two can be effectively welded and fixed.

[0019] By embedding and fixing the support member in the joint, the first end of the metal layer can be supported and fixed, so that the first end of the metal layer can maintain a stable position even in a molten state. During the welding process, the support member can always be fixed. Therefore, during the elastic expansion and contraction of the second end of the metal layer, the first end of the metal layer will basically not be affected by the displacement, thereby maintaining the basic stability of the metal layer structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of an induction welding joint of a PE pipe fitting in Example 1;

[0021] Figure 2 It is a cross-sectional view of an induction welding joint of a PE pipe fitting in Example 1;

[0022] Figure 3 This is a schematic diagram of the external structure of an induction welding joint of a PE pipe fitting in Example 1;

[0023] Figure 4 It is a cross-sectional view of an induction welding joint of a PE pipe fitting in Example 2;

[0024] Figure 5 is a schematic diagram of the structure of the metal layer in Example 2;

[0025] Figure 6 This is a schematic diagram of the structure after the joint body and the pipe body are connected in the second embodiment.

[0026] Figure numerals: joint body 1; interface 2; first cooling zone 21; second cooling zone 22; metal layer 3; first end 31; second end 32; lining layer 33; limiting portion 4; observation hole 5; first observation hole 51; second observation hole 52; support member 6; tube body 7. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Embodiment 1

[0029] This embodiment discloses a PE pipe induction welding joint, referring to Figure 1 , Figure 2 and Figure 3 As shown, the connector body 1 includes a metal layer 3 on the inner peripheral wall of the interface 2, and the connector body 1 and the metal layer 3 are integrally injection molded; the metal layer 3 is annular in structure, and the metal layer 3 is lined with the inner layer of the interface 2. During induction welding, an electromagnetic heater is used to heat the connector body 1, and electromagnetic induction is used to generate eddy currents in the metal layer 3 to achieve heating, thereby melting the material near the metal layer 3, so that the connector body 1 and the inserted pipe body 7 can be welded, and the two can be fixed by electromagnetic induction welding.

[0030] Taking a tee as an example, the joint body 1 has three interfaces, at least one of which has a metal layer 3 inside, which can realize electromagnetic induction welding.

[0031] In order to realize the circulation of molten material, a number of channels are opened on the side wall of the metal layer 3, and the inner and outer layers of the metal layer 3 can be connected through the channels, so that the molten plastic material can flow smoothly. On the one hand, during the injection molding process, the material of the joint body 1 can partially pass through the metal layer 3, so that the metal layer 3 and the joint body 1 can be adhered to form a whole; on the other hand, during the welding process of the joint body 1 and the tube body 7, the molten plastic material can flow inside and outside the metal layer 3 and blend with each other, ensuring that the two can be welded to form a whole, which is beneficial to the strength of the welding between the two.

[0032] Specifically, the metal layer 3 can be made of stainless steel, which has good anti-rust properties. After welding, it can avoid rust inside and extend the service life of the pipe. The structure of the metal layer 3 can be a mesh structure made of stainless steel wire, with a plurality of through holes formed on the surface, that is, as the above-mentioned channels.

[0033] An observation hole 5 is provided on the side wall of the interface 2, one end of the observation hole 5 can be connected to the vicinity of the metal layer 3, and the other end is open to the outer wall of the interface 2. During the induction welding process, the material near the metal layer 3 will be melted by heat, and the melted material has a certain fluidity. When the tube body 7 is inserted and squeezed, the molten material will enter the observation hole 5 and gradually overflow to the observation hole 5, indicating that the welding of the two has been completed and the induction power supply can be removed. The observation hole 5 can facilitate the operator to observe and judge the welding situation.

[0034] Reference Figure 1 , Figure 2As shown, a protruding stopper 4 is formed on the inner periphery of the interface 2. The stopper 4 is generally an annular protrusion structure and has a stepped surface facing the interface 2. When the tube body 7 is inserted into the interface 2, the end of the tube body 7 can abut against the stopper 4 to ensure that the tube body 7 has a certain depth when inserted into the interface 2, thereby ensuring the strength performance of the two after welding.

[0035] Along the axial direction of the interface 2, the two ends of the metal layer 3 are respectively a first end and a second end, wherein the first end 31 of the metal layer 3 is facing the open side of the interface 2, the second end 32 of the metal layer 3 is facing away from the open side of the interface 2, and the second end 32 is facing the direction of the limiting portion 4.

[0036] Along the axial direction of the interface 2, the length of the metal layer 3 is shorter than the distance from the opening of the interface 2 to the limiting portion 4, and the metal layer 3 cannot completely cover the range from the opening of the interface 2 to the limiting portion 4. A first cooling zone 21 is formed between the first end 31 of the metal layer 3 and the opening of the interface 2, and a second cooling zone 22 is formed between the second end 32 of the metal layer 3 and the limiting portion 4. The metal layer 3 is not provided at the first cooling zone 21 and the second cooling zone 22. During the induction welding process, the materials at the first cooling zone 21 and the second cooling zone 22 will not be melted. When the molten material flows to the first cooling zone 21 and the second cooling zone 22, the temperature will decrease, and cooling blocking areas can be formed at the axial ends of the metal layer 3 to prevent the molten material from overflowing the welding area, thereby preventing the situation of material shortage and cold welding, and ensuring that the welding fixation can be stably achieved in the connection area.

[0037] This embodiment also discloses an induction welding method for PE pipe fittings, which performs welding processing on the pipe body 7 and the induction welding joint of the PE pipe fittings in the above embodiment. The outer diameter of the pipe body 7 and the inner diameter of the interface 2 are mutually adapted, and the end of the pipe body 7 can be inserted into the interface 2. The insertion depth of the pipe body 7 can be positioned by the limiting portion 4.

[0038] During welding, first insert the tube body 7 to be welded into the interface 2, and use electromagnetic induction heating to heat the metal layer 3 in the interface 2. The materials of the inner layer of the interface 2 and the outer layer of the tube body 7 melt after being heated, and after cooling, the joint body 1 and the tube body 7 are welded and fixed to each other.

[0039] During welding, observe whether there is material overflow through the observation hole 5 to determine whether the induction heating is completed. When there is material overflow, the heating effect is achieved and the power supply of the induction heating can be turned off. After welding is completed, the welded part of the pipe needs to be kept for 3-8 minutes without shaking or displacement to prevent desoldering.

[0040] By adopting electromagnetic induction to perform welding, the labor and material costs of traditional electric fusion welding wire wiring can be reduced. Induction welding has lower requirements for the metal layer 3, which can significantly reduce the manufacturing cost of the joint.

[0041] Traditional electric fusion welding has very high requirements on welding voltage, and the welding process needs to connect the joints of the wires, which is not only cumbersome to operate, but also has certain safety hazards. Electromagnetic induction does not have high requirements on voltage, and there is no strict requirement on voltage at the construction site. It is easy to operate, safe and reliable.

[0042] In traditional electric fusion welding, the metal mesh in the joint needs to flow current to act as a heating wire, so there are certain requirements for the continuity of the metal mesh. Problems such as broken wires and short circuits are prone to occur inside the joint of electric fusion welding, and local welding leaks are prone to occur during welding, which in turn causes local water leakage problems. In the solution of this embodiment, the metal layer 3 is heated by electromagnetic induction, and the eddy current inside the metal material is used to generate heat. As long as there is metal material in the induction area, heating can be achieved. Induction welding is relatively stable, and the existence of broken wires and short circuits will not affect the actual welding effect.

[0043] Embodiment 2

[0044] This embodiment discloses a PE pipe induction welding joint. Figure 4 , Figure 5 and Figure 6 The shape and structure of the metal layer 3 are further designed in detail.

[0045] Reference Figure 4 , Figure 5 As shown, in this embodiment, the metal layer 3 is an annular spring-like structure and has certain elastic properties and can be elastically expanded and contracted along the length direction.

[0046] Furthermore, the metal layer 3 gradually shrinks toward the second end 32 to form a constricted structure. An inner lining layer 33 is formed between the metal layer 3 and the inner circumferential surface of the interface 2. The inner lining layer 33 has a certain thickness, and its thickness is slightly thicker at the first end 31 of the metal layer 3, and its thickness gradually shrinks toward the second end 32.

[0047] During the electromagnetic welding process, the joint 2 can be preheated first, and the material near the metal layer 3 will gradually melt due to the heat. Since the lining layer 33 at the inner periphery of the second end 32 of the metal layer 3 is thinner, it is also easier to melt completely, while the lining layer 33 at the inner periphery of the first end 31 of the metal layer 3 is thicker and cannot be completely melted in a short time.

[0048] After preheating, the tube body 7 to be welded is inserted into the interface 2. During the insertion process, since the vicinity of the second end 32 of the metal layer 3 has melted, the outer peripheral wall of the tube body 7 can adhere to the material near the second end 32 of the metal layer 3, thereby driving the second end 32 of the metal layer 3 to move toward the limit portion 4. The spring-shaped metal layer 3 will also be driven, thereby causing the metal layer 3 to elastically stretch, and the second end 32 of the metal layer 3 will stretch toward the limit portion 4.

[0049] Then, electromagnetic induction heating is continued to heat the metal layer 3 in the interface 2, and the materials of the inner layer of the interface 2 and the outer layer of the tube body 7 continue to be heated and gradually melted until the lining layer 33 on the inner periphery of the first end 31 of the metal layer 3 is also completely melted.

[0050] After the metal layer 3 is elastically stretched, as the material near the metal layer 3 melts, the second end 32 of the metal layer 3 will elastically recover, and the second end 32 will elastically retract toward the first end 31, thereby driving the material near the second end 32 of the metal layer 3 to move, and the molten material will gather from the second end 32 toward the first end 31 of the metal layer 3, so that the material near the second end 32 of the metal layer 3 can gather in the middle section of the metal layer 3, and then the molten material can achieve melt welding in the middle section of the metal layer 3, ensuring that the two can be welded and fixed.

[0051] After the molten material cools down, the joint body 1 and the tube body 7 can be welded and fixed to each other.

[0052] Furthermore, for joints with larger pipe diameters, a flexible metal mesh layer structure can be coated on the outer periphery of the spring-shaped metal layer 3, so that a metal layer covering structure can also be formed outside the spring-shaped metal layer 3, thereby facilitating eddy currents in the spring-shaped metal layer 3 and the metal mesh, making it easier to achieve heating. Moreover, the metal mesh is also partially bonded and fixed to the spring-shaped metal layer 3, and the flexible metal mesh will not affect the elastic expansion and contraction of the metal layer 3.

[0053] Reference Figure 5 As shown, a support member 6 is embedded in the joint 2, and the support member 6 is a rod-shaped structure. A portion of the support member 6 is fixedly connected to the first end 31 of the metal layer 3, and another portion extends toward the joint body 1 and is embedded and fixedly connected to the joint body 1.

[0054] By pre-embedding the support member 6 in the joint 2, the first end 31 of the metal layer 3 can be supported and fixed. Moreover, since the first end 31 of the metal layer 3 is connected to the support member 6, part of the support member 6 is pre-embedded in the middle section of the joint 2, the support member 6 can always be fixed during the welding process, so at the second end 32 of the metal layer 3, during the elastic expansion and contraction process, the first end 31 of the metal layer 3 is basically not affected by the displacement, thereby maintaining the basic stability of the structure of the metal layer 3.

[0055] Furthermore, two observation holes 5 are provided on the side wall of each interface 2, namely, a first observation hole 51 and a second observation hole 52. The first observation hole 51 is opened at the peripheral position of the first end 31 of the metal layer 3, and the second observation hole 52 is opened at the peripheral position of the second end 32 of the metal layer 3, so that the melting conditions of the materials at two positions can be realized at the two observation holes 5, thereby ensuring that the melting conditions at multiple positions can be obtained in the length direction of the metal layer 3, which is conducive to conveniently observing the melting state of the materials in the interface 2.

[0056] Reference Figure 6 As shown, the joint body 1 includes two joints 2, which are arranged in a coaxial direction. The two joints 2 axially penetrate the two ends of the joint body 1, and the two ends are open.

[0057] Furthermore, metal layers 3 are provided on the inner walls of the two joints 2, and the support member 6 adopts a rod-shaped structure, and both ends of the support member 6 are fixedly connected to the two joints 2 on both sides. The middle section of the support member 6 is pre-buried and fixed in the joint 2. During the welding process, the metal layer 3 on one side will melt during the welding process, while the metal layer 3 on the other side will always remain in a fixed state and can be supported by the joint body 1. In addition, multiple support members 6 are fixedly connected outside the two metal layers 3, and multiple support members 6 can be provided in the circumferential direction of the metal layer 3 for support, thereby ensuring that the two metal layers 3 can be stably supported and the stability of the metal layer 3 can be maintained.

[0058] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A PE pipe induction welding joint, characterized in that: The invention comprises a joint body (1), wherein the joint body (1) comprises an interface (2), the inner peripheral wall of the interface (2) is provided with a metal layer (3), the joint body (1) and the metal layer (3) are integrally injection molded, the metal layer (3) is in an annular structure, and is provided with a channel penetrating the inner and outer peripheries of the metal layer (3); a protruding limiting portion (4) is formed on the inner periphery of the interface (2), and the limiting portion (4) is used to block and position a tube body (7) inserted into the interface (2); the open side of the metal layer (3) facing the interface (2) is a first end (31), and the other end is a second end (32); a first cooling zone (21) is formed between the first end (31) of the metal layer (3) and the open side of the interface (2), and a second cooling zone (22) is formed between the second end (32) of the metal layer (3) and the limiting portion (4).

2. A PE pipe induction welding joint according to claim 1, characterized in that: The metal layer (3) is an annular spring-like structure, and the metal layer (3) can elastically expand and contract along the length direction.

3. A PE pipe induction welding joint according to claim 2, characterized in that: The metal layer (3) gradually decreases toward the second end (32), an inner lining layer (33) is formed between the metal layer (3) and the inner circumferential surface of the interface (2), and the thickness of the inner lining layer (33) gradually decreases toward the second end (32) of the metal layer (3).

4. The PE pipe induction welding joint according to claim 1, characterized in that: The side wall of the interface (2) is provided with two observation holes (5), namely a first observation hole (51) and a second observation hole (52); the first observation hole (51) is located at the periphery of the first end (31) of the metal layer (3); and the second observation hole (52) is located at the periphery of the second end (32) of the metal layer (3).

5. The PE pipe induction welding joint according to claim 2, characterized in that: It also comprises a support member (6), the support member (6) being a rod-shaped structure, a portion of the support member (6) being fixedly connected to the first end (31) of the metal layer (3), and another portion of the support member (6) extending toward the joint body (1) and being pre-buried and fixedly connected to the joint body (1); The joint body (1) comprises two joints (2), the two joints (2) are arranged in a coaxial direction, the inner walls of the two joints (2) are both provided with the metal layer (3), and the two ends of the support member (6) are fixedly connected to the two joints (2) on both sides.

6. The PE pipe induction welding joint according to claim 1, characterized in that: The metal layer (3) is a metal mesh structure, and a plurality of through holes are provided on the side wall of the metal layer (3).

7. The PE pipe induction welding joint according to claim 6, characterized in that: The side wall of the interface (2) is provided with an observation hole (5), one end of the observation hole (5) can be connected to the metal layer (3), and the other end is open toward the outer wall of the interface (2).

8. An induction welding method for PE pipe fittings, characterized in that: It comprises a pipe body (7) and a PE pipe induction welding joint as described in any one of claims 1 to 7, wherein the outer diameter of the pipe body (7) is matched with the inner diameter of the interface (2); the pipe body (7) is inserted into the interface (2), and the metal layer (3) in the interface (2) is heated by electromagnetic induction heating, and the materials of the inner layer of the interface (2) and the outer layer of the pipe body (7) are melted after being heated, and after cooling, the joint body (1) and the pipe body (7) are welded and fixed to each other.

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