Welding seam single-face induction heating device

Abstract

The utility model relates to the technical field of welding, and discloses a weld joint single-face induction heating device, which comprises at least one induction working part, the induction working part is controlled by a control cabinet to work, the induction working part comprises an induction coil and a framework for supporting the induction coil, an electric wire in the induction coil is a nickel-plated copper wire, and the framework is arranged in the nickel-plated copper wire. The framework is laid on a workpiece, and the induction coil is aligned with a working part and starts to act after being electrified, so that the working part is induced to automatically heat. The bendable framework is adopted, so that the surface of a weld joint is better attached; by adopting the double-layer wound coil, the inductance range of the single coil can be effectively expanded under the condition that the wire diameter is not increased, so that the maximum output power of the single coil is improved; nickel-plated copper wires are adopted, the coil temperature is effectively reduced by about 100 DEG C, and the effect is obvious; the temperature difference between the inner side and the outer side of the welding seam in the stable heat preservation process meets the process requirement.

Description

Technical Field

[0001] The utility model relates to the technical field of welding, in particular to a single-sided induction heating device for a weld. Background Art

[0002] Welding, also known as fusion or melting, is a manufacturing process that joins metals or other thermoplastic materials, such as plastics, using heat, high temperature, or high pressure. Welding residual stress is caused by the uneven temperature distribution of the weldment during welding, as well as the thermal expansion and contraction of the weld metal. Therefore, residual stress is inevitably generated during welding. The commonly used post-weld heat treatment method is to heat the weldment to a certain temperature in a heat treatment furnace and hold it there for a certain period of time. This method utilizes the lowering of the material's yield strength at high temperatures to induce plastic flow in areas of high internal stress, gradually reducing elastic deformation and increasing plastic deformation, thereby reducing stress.

[0003] The effect of post-weld heat treatment on the tensile strength and creep limit of metals is related to the heat treatment temperature and holding time. The effect of post-weld heat treatment on the impact toughness of the weld metal varies with the type of steel. Heat treatment heating and cooling should not be too rapid, and strive for uniformity between the inner and outer walls.

[0004] As manufactured products continue to grow in size, the volume and weight of equipment have increased, leading to an increase in the thickness of equipment components. Pressure vessel specifications are rapidly developing towards thicker walls, with thickness increasing from the initial 40mm to the current common 70mm. This poses significant difficulties and challenges to the single-sided post-weld heat treatment of pressure vessel welds. Single-sided heat treatment of thick-walled welds, a key challenge in the field of post-weld heat treatment of pressure vessels, has a significant impact on the manufacturing quality of large pressure vessels.

[0005] In existing technology, induction heating is used to heat treat thick-walled welds on one side after welding. While induction heating, which utilizes the workpiece's own heat generation, can theoretically meet process requirements, existing induction heating tooling and equipment struggle to adapt to the high-pressure environment of single-sided post-weld heat treatment, such as 70mm thick welds, and the temperature difference between the inner and outer weld surfaces. Therefore, a single-sided induction heating device is needed to handle 70mm thick welds on one side after welding to meet processing standards. Summary of the Invention

[0006] The utility model addresses the deficiencies in the prior art and provides a single-sided induction heating device for a weld, comprising at least one induction working part, which is controlled by a control cabinet to operate, the induction working part comprising an induction coil and a skeleton supporting the induction coil, the wires in the induction coil being nickel-plated copper wire, the skeleton being laid on a workpiece, the induction coil being aligned with the working part and starting to work after being energized, so that the working part is induced to heat itself.

[0007] Preferably, it further comprises a circulating water cooling unit, wherein the circulating water cooling unit comprises a water chiller and a cooling water pipeline, and the cooling water pipeline is connected to the control cabinet.

[0008] Preferably, the skeleton includes a plurality of intermediate support bars and a plurality of peripheral support bars, the intermediate support bars are used for connecting and installing the induction coil, and the peripheral support bars are used for fixing and installing the peripheral support bars.

[0009] Preferably, the peripheral support bars are divided into two groups, and the peripheral support bars in each group are rotatably connected to form a line. The peripheral support bars have elastic deformation properties and can be wound around the surface of the workpiece.

[0010] Preferably, the control cabinet includes a display panel, a control panel and a circuit control device, and the control cabinet controls one or more sensing working parts to work simultaneously or independently.

[0011] Preferably, the induction coil is wound with double-layer wires, and wiring at both ends is reserved for connecting to a control cabinet.

[0012] Preferably, the outer insulation layer of the weld is wrapped with a double layer of insulation cotton, and the inner side is insulated and fixed with a single layer of insulation cotton.

[0013] Compared with the existing technology, the beneficial effects of the present invention are: a flexible skeleton is adopted to better fit the weld surface; a double-layer wound coil is adopted, which can effectively expand the inductance range of the single-chip coil without increasing the wire diameter, thereby increasing the maximum output power of the single-chip coil; nickel-plated copper wire is used, and the coil temperature is effectively reduced by about 100°C, with obvious effects; the temperature during the heat treatment process is relatively uniform, and the temperature difference between the inside and outside of the weld during the stable insulation process meets the process requirements, the color of the outer surface of the weld is uniform, and the hardness of each point reaches the weld hardness standard after heat treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be discussed below. Obviously, the technical solutions described in conjunction with the drawings are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments and their drawings can be obtained based on the embodiments shown in these drawings without paying any creative work.

[0015] Figure 1 The utility model is a structural schematic diagram of a single-sided induction heating device for a weld.

[0016] Figure 2 The utility model is a schematic diagram of the connection between a cooling cabinet and a control cabinet of a single-sided induction heating device for a weld.

[0017] Figure 3 The utility model is a schematic diagram of the cooling cabinet structure of a single-sided induction heating device for a weld.

[0018] Figure 4 The utility model is a schematic diagram of the connection between a control cabinet and a heating component of a single-sided induction heating device for a weld.

[0019] Figure 5 The utility model is a schematic diagram of a single coil structure of a single-sided induction heating device for a weld.

[0020] Figure 6 The utility model is a schematic diagram of a double-coil structure of a single-sided induction heating device for a weld.

[0021] Figure 7 This is a schematic diagram of a heating temperature control system for a single-sided induction heating device for a weld in the utility model.

[0022] Figure 8 The utility model is a cross-sectional schematic diagram of a single-sided induction heating device for a weld seam heating a workpiece.

[0023] In the figure: 1-induction coil, 11-skeleton, 12-peripheral support strip, 2-control cabinet, 3-water chiller, 31-cooling water pipeline, 4-thermocouple, 41-insulation cotton layer. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions of various embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments described in 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.

[0025] The embodiments of the present utility model provide, as Figures 1 to 8 The device, shown in Figure 1, illustrates a single-sided induction heating device for a weld seam. The device comprises one or more induction working units, controlled by a control cabinet 2. These units include an induction coil 1 and a support frame 11, which is placed on a workpiece. The induction coil 1 is a double-layer nickel-plated copper coil, replacing the original pure copper coil, to increase coil output power. The induction coil 1 is aligned with the working unit and begins operating upon power-up, causing the working unit to generate heat through induction.

[0026] The skeleton 11 includes a plurality of intermediate support bars and a plurality of peripheral support bars 12. The intermediate support bars are used to connect and install the induction coil 1, and the peripheral support bars 12 are used to fix and install the peripheral support bars 12. The peripheral support bars 12 are divided into two groups. The peripheral support bars 12 in each group are rotatably connected to form a straight line. The peripheral support bars 12 have elastic deformation properties and can be wound around the surface of the workpiece.

[0027] The outer insulation layer of the weld is wrapped with a double-layer wide insulation layer 41, and the inner layer is insulated and secured with a single layer of insulation layer 41. Several main control thermocouples 4 are placed on the weld directly below the heating fixture; several monitoring thermocouples 4 are placed in the gap between adjacent fixtures to monitor the temperature there; and several internal monitoring thermocouples 4 are placed inside the weld to detect the temperature of the inner surface of the weld.

[0028] The control cabinet 2 includes a display panel, a control panel, and a circuit control device. The control cabinet 2 controls one or more induction working parts to operate simultaneously or independently. The induction coil 1 is made of double-layered wire, and sufficient wire length is reserved at both ends for connection to the control cabinet 2.

[0029] The device is mounted on the workpiece using a frame 11, and then uses the energized induction coil 1 to act on the workpiece. For larger workpieces, multiple induction working parts can be connected and used.

[0030] It also includes a circulating water cooling unit, which includes a water cooler 3 and a cooling water pipeline 31. The cooling water pipeline 31 is connected to the control cabinet 2. The heat of the control cabinet 2 is transferred through the cooling water pipeline 31 set in conjunction with the water cooler 3, replacing the forced air cooling system to cool the induction heating power supply, reducing the power supply start and stop frequency and increasing output efficiency.

[0031] At the same time, the frequency of the alternating current of the equipment is reduced and the penetration depth of the current is increased.

[0032] The entire set of equipment was put into practical use on the 7155-7122 A09 weld of Zhenhai Refining and Chemical. After heat treatment, the hardness value of the workpiece was relatively uniform, with an average hardness of 192.6HB at the weld. The hardness result met the process requirement of ≤225HB.

[0033] In summary, in this Zhenhai Refining and Chemical 7155-7122 A09 weld 70mm thick single-sided post-weld heat treatment project, the temperature was relatively uniform throughout the heat treatment process, and the temperature difference between the inside and outside of the weld during the stable insulation process met the process requirements. After the heat treatment, the color of the weld outer surface was uniform, the hardness test results were ideal, and the hardness of each point was within the standard range of the weld hardness after heat treatment, achieving the expected project goals.

[0034] The outer insulation layer is wrapped with a double layer of 900mm wide, 30mm thick insulation cotton, while the inner layer is insulated and secured with a single layer of 900mm wide, 30mm thick insulation cotton. The outer heating layer is set up with four 970mm*540mm induction fixtures, with approximately 144mm spacing between each fixture, meeting the requirement of maintaining a 60mm-180mm gap between each fixture. Each fixture has an output power of 60kW, which can meet the power requirements of the heat treatment.

[0035] Induction heating technology uses electromagnetic induction to generate eddy currents within the material being heated. These eddy currents move within the workpiece, generating a resistive heating effect that heats the workpiece surface. As shown in the table above, the use of nickel-plated copper wire effectively reduces coil temperature by approximately 100°C, a significant improvement.

[0036] Regarding coil winding, after numerous experiments, we found that double-layer winding can effectively expand the inductance range of a single coil without increasing the wire diameter, thereby increasing the maximum output power of the single coil. Nickel-plated copper wire was used instead of pure copper wire to avoid the heat generation caused by oxidation of pure copper wire at high temperatures. The specific heating test results are shown below:

[0037]

[0038] As can be seen from the above table, the maximum output power of a single-layer induction heating tool is 50kw, while the maximum output power of a double-layer induction heating coil can reach 58kw, effectively increasing the maximum output power by 15%, providing maximum power support for single-sided post-weld heat treatment of thick-wall welds.

[0039] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered in all respects as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims, not the foregoing description, and it is intended that all variations within the meaning and scope of equivalents of the claims be encompassed within the present invention. Any reference numerals in the claims should not be construed as limiting the claim to which they relate.

[0040] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A single-sided induction heating device for a weld, characterized by: The invention comprises at least one induction working part, wherein the induction working part is controlled by a control cabinet (2) to operate, and the induction working part comprises an induction coil (1) and a skeleton (11) supporting the induction coil (1). The wire in the induction coil (1) is nickel-plated copper wire. The skeleton (11) is laid on the workpiece. The induction coil (1) is aligned with the working part and starts to work after being energized, so that the working part is induced to heat itself.

2. The weld seam single-sided induction heating device according to claim 1, characterized in that: It also includes a circulating water cooling unit, which includes a water cooler (3) and a cooling water pipeline (31), and the cooling water pipeline (31) is connected to the control cabinet (2).

3. The weld seam single-sided induction heating device according to claim 1, characterized in that: The skeleton (11) includes a plurality of intermediate support bars and a plurality of peripheral support bars (12), wherein the intermediate support bars are used for connecting and installing the induction coil (1), and the peripheral support bars (12) are used for fixing and installing the peripheral support bars (12).

4. The weld seam single-sided induction heating device according to claim 3, characterized in that: The peripheral support strips (12) are divided into two groups. The peripheral support strips (12) in each group are rotated and connected to form a line. The peripheral support strips (12) have elastic deformation properties and can be wound on the surface of the workpiece.

5. The weld seam single-sided induction heating device according to claim 1, characterized in that: The control cabinet (2) comprises a display panel, a control panel and a circuit control device, and the control cabinet (2) controls one or more induction working parts to work simultaneously or independently.

6. The weld seam single-sided induction heating device according to claim 1, characterized in that: The induction coil (1) is wound with double-layer wires, and both ends are reserved for connection to the control cabinet (2).

7. The weld seam single-sided induction heating device according to claim 1, characterized in that: The outer insulation layer of the weld is wrapped with a double-layer insulation cotton layer (41), and the inner side is insulated and fixed with a single layer of insulation cotton layer (41).

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