Special-shaped induction coil for medium-frequency heating of seamless steel pipes in the manufacture of large-volume gas cylinders
By designing a special-shaped induction coil, the problem of uneven heating of steel pipe products in large-volume gas cylinders is solved, local heating and remanufacturing are achieved, and production costs and scrap rate are reduced.
Patent Information
- Application Number
- CN202421518598.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-30
- Publication Date
- 2025-04-11
- Estimated Expiration
- 2034-06-30
AI Technical Summary
In the manufacturing of large-volume gas cylinders, it is difficult to achieve uniform heating of steel pipe products during heating, resulting in unsuccessful molding or serious deformation, resulting in production waste and high cost waste.
A special-shaped induction coil is designed, and a heating substrate that wraps the gas cylinder in a space is made by spiral winding of copper tubes. The turns spacing is adjustable, and the wiring terminals can be selected to form an LC oscillation device, adapt to the changes in the outer diameter of the gas cylinder and concentrate the magnetic field density to achieve local heating.
It effectively solves the local heating problem of steel tubular or bottle-shaped special-shaped parts, reduces the generation of production waste, reduces production costs, and improves the success rate of steel cylinder formation.
Smart Images
Figure CN222740093U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a heating device, in particular to a special-shaped induction coil for medium-frequency heating of seamless steel pipes in manufacturing large-volume gas cylinders. Background Art
[0002] The current volume of gas storage containers is getting larger and larger, and the cost value of a single steel container product is also very high. For example, the manufacture of large-volume gas cylinders for hydrogen and natural gas uses seamless steel pipes with different wall thicknesses for heating, and then spins them into shape through spinning equipment. The heating is achieved by placing the product to be heated in a medium-frequency furnace, and using medium-frequency or high-frequency electromagnetic wave signals to react with the induction coil in the furnace to generate heat, and then producing it after reaching the temperature required for product processing. The size of the heating coil is 545mm in diameter, the heating length is between 550 and 600mm, and the overall shape is a cylindrical inner cavity. Obviously, for steel pipe products with a diameter of 485mm, a wall thickness of 40mm, and a length of 12m, especially partially shaped tube-mounted or bottle-shaped steel products, it is impossible to effectively heat them to achieve the expected uniform heating degree.
[0003] Therefore, for large-volume gas cylinders weighing several tons and having a capacity of several cubic meters, no matter how refined and perfect the processing technology is, the product often fails to form or is severely deformed during spinning. In the past, the conventional practice was either to remake the product but the usability was very small, or to directly scrap it but the loss was too great, both of which affected the normal manufacturing of the product, and it was also a great burden for the company to scrap such a high-cost product. Summary of the invention
[0004] The utility model aims to provide a special-shaped induction coil for medium-frequency heating of seamless steel pipes in the manufacture of large-volume gas cylinders, so that the special-shaped parts of semi-finished products that are not formed according to design requirements can be induction heated to achieve the purpose of reproduction and shaping.
[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a special-shaped induction coil for medium-frequency heating of seamless steel pipes in the manufacture of large-volume gas cylinders, characterized in that: it is a heating substrate that is spirally wound by a copper tube and wraps the gas cylinder in the air, the winding structure of the heating substrate is a diameter that gradually decreases as the shape of the gas cylinder body to the bottle shoulder and then to the bottle mouth changes, and the turn spacing is adjustable, the heating substrate leads to a number of wiring terminals at several positions along the winding direction, and two wiring terminals are selected from them to connect to the medium-frequency equipment to form an LC oscillation device.
[0006] Furthermore, the cross-sectional shape of the copper tube is a flat-mouthed rectangle, and the main cross-sectional shape of the copper tube at the bottle shoulder is horizontal, and the main cross-sectional shape at the transition section from the bottle shoulder to the bottle mouth and the bottle mouth is vertical.
[0007] Furthermore, the turn spacing of the copper tube at the bottle shoulder is similar to that at the bottle body, and the turn spacing at the bottle mouth is reduced.
[0008] Furthermore, the distance between the heating base wound with the copper tube and the surface of the workpiece to be heated gradually decreases from the bottle shoulder to the bottle mouth.
[0009] Furthermore, an outer shell is provided on the outside of the heating substrate, and the outer shell is provided with a replaceable and disassembled thin-walled inner shell which can adapt to the shape and specifications of the workpiece to be heated in close contact with the heating substrate; all the terminal taps pass through the outer shell.
[0010] Furthermore, all the connection terminals are provided with differentiated distinguishing marks according to the lead-out positions.
[0011] Compared with the prior art, the beneficial effects of the utility model are as follows: the special-shaped induction coil solves the problem of local heating of steel tubular or bottle-shaped special-shaped parts, and can heat and optimize the production waste caused by unexpected shutdowns, unformed closing and other factors in the production process of steel cylinders, effectively reducing the huge waste of production costs caused by waste. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Figure 1 It is a schematic diagram of the axial section structure of an application of an embodiment of the special-shaped induction coil of the utility model. DETAILED DESCRIPTION
[0013] The specific implementation methods of the utility model will be further described below in conjunction with the accompanying drawings of the embodiments, so that the technical solution of the utility model is easier to understand and grasp, thereby making a clearer definition of the protection scope of the utility model.
[0014] Aiming at the high cost of existing large-capacity steel gas cylinders and the high scrap rate of spin forming, which causes excessive losses, the designer of the utility model relies on long-term production line experience and innovatively proposes a special-shaped induction coil with targeted local heating and high uniformity of heat distribution, so as to provide the possibility of re-processing and production to correct the forming and prevent scrapping.
[0015] The utility model is a special-shaped induction coil for medium-frequency heating of seamless steel pipes for manufacturing large-volume gas cylinders. The three-dimensional shape of the induction coil is modified according to the special-shaped structure at both ends of the gas cylinder. Figure 1 The schematic diagram of the axial section structure of an embodiment shown in the figure shows that it is a heating base 2 formed by spirally winding a copper tube 21 to wrap the gas cylinder 1 in the air. The winding structure of the heating base 2 is such that the diameter gradually decreases as the shape of the gas cylinder body 11 to the bottle shoulder 12 and then to the bottle mouth 13 changes, and the turn spacing of the copper tube can be adjusted during the winding trial production. As a drive, the heating base leads to several terminals (not shown) at several positions along the winding direction, and two terminals are selected from them to connect to the intermediate frequency device to form an LC oscillation device.
[0016] It can be understood from the above overview that the winding diameter of the copper tube gradually changes to adapt to the change in the outer diameter of the end of the gas cylinder, and the turn spacing of different parts is also different, thereby increasing the magnetic field density of the special-shaped parts, so that the heating heat energy is relatively concentrated. More specifically, the cross-sectional shape of the above-mentioned copper tube 21 is a flat-mouthed rectangle, and the main cross-sectional shape of the copper tube at the bottle shoulder is horizontal, and the main cross-sectional shape passing through the transition section from the bottle shoulder to the bottle mouth and the bottle mouth is vertical. Based on the copper tube winding method, the turn spacing a of the copper tube at the bottle shoulder is referenced to the bottle body, the turn spacing b at the transition section from the bottle shoulder to the bottle mouth is slightly reduced, and the turn spacing c at the bottle mouth is the smallest. In addition, for the special-shaped parts that need to be heated and reshaped, the molding process requires that the gas cylinder is not overheated in the bottle body part, while the bottle shoulder and bottle mouth parts are significantly heated. Therefore, the distance of the heating base 2 wound by the copper tube 21 relative to the surface of the workpiece to be heated gradually decreases from the bottle shoulder to the bottle mouth, that is, d1 is slightly greater than d2.
[0017] Of course, the special-shaped induction coil is not directly exposed and outputs heat energy to the workpiece to be heated. It needs to suppress the heat radiation to the surrounding environment and concentrate it on the inner cavity surrounded by the heating base. Therefore, the heating base 2 is provided with an outer shell 3; and in view of the diversity of the shape and specifications of the workpiece to be heated, the outer shell 3 can also be closely attached to the heating base 2 and provided with a thin-walled inner shell 31 that can adapt to the shape and specifications of the workpiece to be heated and can be replaced and disassembled, which is realized by threaded connection or guide groove buckle, etc., and can be flexibly replaced according to changes in product batches.
[0018] The above-mentioned terminals include at least one terminal led out from the copper tube of the heating substrate in the bottle body section, at least one terminal led out from the copper tube of the heating substrate in the bottle shoulder section, and at least three terminals led out from the copper tube of the heating substrate in the bottle shoulder and bottle mouth transition section or bottle mouth. And these terminals can also be optionally provided with differentiated distinguishing marks according to their respective lead-out positions, such as various colored skins or adhesive labels. All the terminals are tapped out of the housing. In actual use, it is only necessary to select the corresponding terminals at the two ends of the outer periphery of the area according to the special-shaped range to be heated and connect them to the intermediate frequency equipment to achieve efficient heating in the required range, while the remaining terminals are left vacant or protected by sheaths.
[0019] From the above introduction to the design scheme and detailed description of the embodiment of the special-shaped induction coil of the utility model, it can be seen that it has substantial characteristics and progress: the special-shaped induction coil solves the problem of local heating of steel tubular or bottle-shaped special-shaped parts, and can heat and optimize the production waste caused by factors such as unexpected shutdown and unformed closing in the production process of steel cylinders, effectively reducing the huge waste of production costs caused by waste. Taking the large container steel pipe products described in the background technology as an example, the weight of a single product is about 5 tons, and the direct cost is about 60,000 yuan. It can be seen that reducing the output of each waste product will bring significant benefits to the production enterprise.
[0020] In addition to the above embodiments, the present invention may also have other implementation modes, and any technical solutions formed by equivalent replacement or equivalent transformation shall fall within the scope of protection required by the present invention.
Claims
1. A special-shaped induction coil for medium-frequency heating of seamless steel pipes for manufacturing large-volume gas cylinders, characterized by: The heating substrate is a heating substrate which is spirally wound from a copper tube and wraps around a gas cylinder in the air. The winding structure of the heating substrate has a diameter which gradually decreases as the shape of the gas cylinder body, the bottle shoulder and then to the bottle mouth changes, and the turn spacing is adjustable. The heating substrate leads to a number of terminals at several positions along the winding direction, and two of the terminals are selected to connect to the intermediate frequency equipment to form an LC oscillation device.
2. The special-shaped induction coil for medium-frequency heating of seamless steel pipes for manufacturing large-volume gas cylinders according to claim 1 is characterized in that: The cross-sectional shape of the copper tube is a flat-mouthed rectangle, and the main cross-sectional shape of the copper tube at the bottle shoulder is horizontal, and the main cross-sectional shape at the transition section from the bottle shoulder to the bottle mouth and the bottle mouth is vertical.
3. The special-shaped induction coil for medium-frequency heating of seamless steel pipes for manufacturing large-volume gas cylinders according to claim 1 is characterized in that: The turn spacing of the copper tube at the bottle shoulder is the same as that at the bottle body, and the turn spacing at the bottle mouth is reduced.
4. The special-shaped induction coil for medium-frequency heating of seamless steel pipes for manufacturing large-volume gas cylinders according to claim 1 is characterized in that: The distance between the heating base wound with the copper tube and the surface of the workpiece to be heated gradually decreases from the bottle shoulder to the bottle mouth.
5. The special-shaped induction coil for medium-frequency heating of seamless steel pipes for manufacturing large-volume gas cylinders according to claim 1 is characterized in that: The heating base is covered with an outer shell, and the outer shell is closely attached to the heating base and provided with a thin-walled inner shell which can adapt to the shape and specification of the workpiece to be heated and can be replaced and disassembled; all the terminal taps pass through the outer shell.
6. The special-shaped induction coil for medium-frequency heating of seamless steel pipes for manufacturing large-volume gas cylinders according to claim 5 is characterized by: All wiring terminals are marked with differentiated markings according to their lead-out locations.