Electromagnetic induction heating device for heat treatment of connecting pipe

Abstract

The utility model relates to an electromagnetic induction heating device for heat treatment of a connecting pipe, which comprises two opposite annular end plates, a plurality of supporting rods are coaxially and uniformly distributed around the circle center between the opposite surfaces of the two annular end plates, two ends of each supporting rod are respectively fixed on the annular end plates through bolts, and a cable is wound on the outer circumference formed by the plurality of supporting rods. A heat preservation layer is wound on the outer circumference of the cable in a covering mode, grooves for containing the cable are formed in the outer side face of the circumference where the multiple supporting rods are located in the axial direction, and after the cable is wound and arranged in the grooves, the outer circumferential face where the cable is located is flush with the outer circumferential face of the annular end plate. An operator only needs to quickly plug the heating device into the inner wall of the connecting pipe and start a power supply to heat according to a pre-set process program, so that the purpose of immediately eliminating hydrogen after welding can be achieved, the risk of welding cracks is reduced, the performance of a welding joint is improved, and the product quality is improved; the device has the advantages of high efficiency, energy conservation, environmental protection, safety, high heating speed, high temperature control precision and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of thermal power generation equipment, in particular to an electromagnetic induction heating device for heat treatment of a pipe. Background Art

[0002] After welding, the internal residual stress of the inner wall of the pipe of the serpentine tube inside the high-pressure heater cannot be effectively removed, the hardness of the welded joint cannot be guaranteed, and crack defects are prone to occur, which requires heat treatment to eliminate stress. Due to the special structure of the serpentine high-pressure heater, the inlet and outlet headers and the pipes extending from the header are thick, and the material is 15NiCuMoNb alloy steel. It can only be heated from the inner wall of the pipe, and the inner wall is measured for temperature, the inner wall is dehydrogenated and locally heat treated. The use of traditional flame heating pipes during heat treatment has high energy consumption costs and difficult to accurately control the temperature. Ensuring the temperature difference between the inside and the outside has always been a difficult problem in local heat treatment. Due to the large temperature difference between the inside and the outside during heating, traditional flame heating requires continuous heating of the workpiece by burning gas, and flame heating needs to be carried out by propane gas cylinders. The main problems are low degree of automation, high cost of use, uneven and difficult to control temperature distribution, carbon deposition and blackening of the heating part affecting the quality of the weld, and the generation of polluted gas, resulting in a poor working environment for on-site operators; there is also a method of using ceramic sheet resistance heating, which has a long preparation time, high equipment depreciation rate, high energy consumption, uneven heating temperature, and a large temperature difference between the inside and the outside. Both of the above methods cannot ensure that the inner and outer wall temperatures meet the heat treatment process requirements. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide an electromagnetic induction heating device for heat treatment of a pipe, so as to solve the problem of heat treatment of the inner wall of the pipe inside the serpentine tube high-pressure heater after welding.

[0004] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0005] An electromagnetic induction heating device for heat treatment of pipes comprises two opposite annular end plates, a plurality of support rods are coaxially distributed around the center of the circle between the opposite surfaces of the two annular end plates, the two ends of the support rods are respectively fixed to the annular end plates by bolts, a cable is wound around the outer circumference formed by the plurality of support rods, and the outer circumference of the cable is covered and wound with a thermal insulation layer.

[0006] As a preferred embodiment, grooves for accommodating cables are axially arranged on the circumferential outer surface where the plurality of support rods are located. After the cables are wound and arranged in the grooves, the outer circumferential surface where the cables are located is flush with the outer circumferential surface of the annular end plate.

[0007] As a preferred embodiment, the material of the thermal insulation layer includes thermal insulation asbestos and high silica cloth.

[0008] As a preferred embodiment, two perforated plates are fixed on the inner circumference of the annular end plate on one side by bolts, and the two ends of the cable extend out from the through holes of the two perforated plates.

[0009] As a preferred implementation scheme, the annular end plate and the support rod are made of high temperature resistant glass fiber board, and the cable is made of high temperature resistant alloy induction heating cable.

[0010] As a preferred implementation, the orifice plate is made of a high temperature resistant glass fiber board.

[0011] The beneficial effects of the utility model are as follows: the heating device utilizes the electromagnetic induction principle to carry out dehydrogenation and local heat treatment on the connecting pipe, and the whole is made of high-temperature resistant materials, which can quickly heat the connecting pipe, and the heating effect of the entire welding joint can achieve the purpose of eliminating the residual stress of the welding joint and reducing the hardness of the welding joint. The worker is convenient to operate and use. After the welding of the weld seam on the inner wall of the connecting pipe is completed, the operator only needs to quickly insert the heating device into the inner wall of the connecting pipe, start the power supply and heat it according to the pre-planned process procedure, which can achieve the purpose of immediate dehydrogenation after welding, reduce the risk of welding cracks, improve production efficiency, reduce production costs, improve the performance of welding joints, and improve product quality. It has the advantages of high efficiency and energy saving, environmental protection and safety, fast heating speed, and high temperature control accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings, wherein:

[0013] Figure 1 It is a front view of the utility model;

[0014] Figure 2 It is a side view of the utility model;

[0015] Figure 3 It is a schematic diagram of the utility model when in use;

[0016] Figure 1~Figure 3 Explanation of the reference numerals in the accompanying drawings: 1. bolt; 2. annular end plate; 3. insulation layer; 4. support rod; 41. groove; 5. cable; 6. orifice plate; 7. connecting pipe. DETAILED DESCRIPTION

[0017] The specific implementation scheme of the utility model is described in detail below in conjunction with the accompanying drawings.

[0018] like Figure 1~Figure 3 The electromagnetic induction heating device for heat treatment of the pipe shown includes two opposite annular end plates 2, and a plurality of support rods 4 are coaxially distributed around the center between the opposite surfaces of the two annular end plates 2. The two ends of the support rods 4 are respectively fixed to the annular end plates 2 by bolts 1, and a cable 5 is wound around the outer circumference formed by the plurality of support rods 4, and the outer circumference of the cable 5 is covered and wound with a thermal insulation layer 3.

[0019] Specifically, the heating device is composed of a support rod 4 made of high-temperature resistant fiberglass board, annular end plates 2 made of high-temperature resistant fiberglass boards at both ends, a cable 5 using a high-temperature resistant alloy induction cable, and an insulation layer 3 composed of insulating asbestos wrapped with high-silica cloth. The whole is made of high-temperature resistant materials. When in use, the entire heating device is inserted into the inner cavity of the connecting pipe 7, and the cable 5 heats the connecting pipe 7 using the principle of electromagnetic induction heat generation. The insulation layer 3 contacts the inner wall of the connecting pipe 7 and keeps it warm. The heating process is controllable and simple to clean.

[0020] like Figure 2 The outer circumferential surface of the plurality of support rods 4 is provided with grooves 41 for accommodating the cables 5 arranged axially. After the cables 5 are wound and arranged in the grooves 41, the outer circumferential surface of the cables 5 is flush with the outer circumferential surface of the annular end plate 2, so as to fit more closely into the inner circumference of the pipe 7. The grooves 41 allow the arrangement of the cables 5 to be orderly and regular, and can better realize the electromagnetic induction phenomenon.

[0021] Wherein, the material of the thermal insulation layer 3 includes thermal insulation asbestos and high silica cloth. Such material can not only withstand high temperatures, but also perform heat insulation and heat preservation, and maintain the temperature of the heat treatment of the pipe 7.

[0022] like Figure 1 Two orifice plates 6 are fixed on the inner circumference of the annular end plate 2 on one side by bolts 1, and both ends of the cable 5 extend out from the through holes of the two orifice plates 6. The orifice plates 6 lead out the cable 5.

[0023] The annular end plate 2 and the support rod 4 are made of high temperature resistant glass fiber board, the cable 5 is made of high temperature resistant alloy induction heating cable, and the orifice plate 6 is made of high temperature resistant glass fiber board. High temperature resistant materials are more suitable for the working environment of heat treatment.

[0024] The working process of the utility model is as follows:

[0025] According to Figures 1-3, first, before heating the inner wall of the pipe 7, the cable 5 is first wound around the high temperature resistant glass fiber board support rod 4, and finally passed through the orifice plate 6 and connected to the electromagnetic induction device. Then the insulation layer 3 is wrapped around the cable 5, so that the whole becomes a heating device. Finally, after the pipe 7 is welded, the heating device is installed inside the pipe 7 that needs to be heated.

[0026] The above embodiments are only illustrative of the principles and effects of the invention of the utility model, as well as some embodiments of its application, and are not intended to limit the invention of the utility model. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the invention, and all of these belong to the protection scope of the invention.

Claims

1. An electromagnetic induction heating device for heat treatment of pipes, characterized in that: The invention comprises two opposite annular end plates (2), a plurality of support rods (4) being coaxially evenly distributed around the center of a circle between opposite surfaces of the two annular end plates (2), two ends of the support rods (4) being respectively fixed to the annular end plates (2) by bolts (1), a cable (5) being wound around the outer circumference formed by the plurality of support rods (4), and a thermal insulation layer (3) being wound around the outer circumference of the cable (5).

2. The electromagnetic induction heating device for heat treatment of pipe connection according to claim 1, characterized in that: Grooves (41) for accommodating the cables (5) are arranged axially on the outer circumferential surface where the plurality of support rods (4) are located. After the cables (5) are wound and arranged in the grooves (41), the outer circumferential surface where the cables (5) are located is flush with the outer circumferential surface of the annular end plate (2).

3. The electromagnetic induction heating device for heat treatment of pipe connection according to claim 1, characterized in that: The material of the thermal insulation layer (3) includes thermal insulation asbestos and high-silica cloth.

4. The electromagnetic induction heating device for heat treatment of pipe connection according to claim 1, characterized in that: Two perforated plates (6) are fixed on the inner circumference of the annular end plate (2) on one side by means of bolts (1), and two ends of the cable (5) extend out from through holes of the two perforated plates (6).

5. The electromagnetic induction heating device for heat treatment of pipe connection according to claim 1, characterized in that: The annular end plate (2) and the support rod (4) are made of high-temperature resistant glass fiber plates, and the cable (5) is made of high-temperature resistant alloy induction heating cable.

6. The electromagnetic induction heating device for heat treatment of pipe connection according to claim 4, characterized in that: The orifice plate (6) is made of a high temperature resistant glass fiber plate.

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