A special steel electroslag remelting consumable electrode rod end preheating device

Abstract

This invention provides an end preheating device for a special steel electroslag remelting consumable electrode rod. The preheating device includes a preheating furnace body and a trolley. One end of the preheating furnace body is provided with an open preheating furnace opening. The preheating furnace body includes an outer shell and an inner cylinder. The inner cylinder is coaxially disposed inside the outer shell, and heating wires are arranged on the inner wall of the inner cylinder. The preheating furnace body is placed horizontally on the trolley. Pushing the trolley can move the preheating furnace body along the axial direction of the electroslag remelting consumable electrode rod. The movement of the preheating furnace body allows the end of the electroslag remelting consumable electrode rod to be preheated to enter the inner cylinder through the preheating furnace opening. When the heating wires are energized, they can preheat the end of the electroslag remelting consumable electrode rod. This preheating device greatly saves investment costs, improves production efficiency, and allows a single person to complete all movement, centering, and furnace loading operations. The operation is simple and quick.

Description

Technical Field

[0001] This invention relates to the field of mechanical manufacturing, and in particular to an end preheating device for a special steel electroslag remelting consumable electrode rod. Background Technology

[0002] In the electroslag remelting workshop of a special steel smelter, round steel bars are commonly used as consumable electrode carriers in the electroslag remelting process. These special steel consumable electrode bars must first have their surface oxide scale removed, and then dummy electrodes welded on before they can enter the electroslag remelting process. The smelting stability of the electroslag remelting process is a core prerequisite for ensuring the internal and external quality of the finished steel. However, for some steel grades, consumable electrode bars retain extremely high thermal stress after casting, rolling, or forging during the cooling process. During the remelting start-up phase, the melting end of the electrode bar may develop end cracks due to an excessively rapid heating rate, or even fragments may fall off and mix into the molten steel. Once such defects occur, only the affected section can be removed during production; in severe cases, it can directly lead to the scrapping of the entire electroslag steel ingot, causing significant production losses.

[0003] To address this industry pain point, traditional production commonly employs two pretreatment methods: stress-relief annealing of the entire special steel consumable electrode rod, or gas baking preheating of the electrode ends before electroslag remelting. However, both processes have the following shortcomings: 1. When using stress-relief annealing, a thick oxide scale will form on the surface of the special steel consumable electrode rod. Subsequently, it is necessary to increase the amount of surface peeling or turning of the special steel consumable electrode rod, resulting in large metal loss, long production cycle and increased cost.

[0004] 2. When using a single-end gas baking process, not only is it impossible to adjust the temperature, but there is also a safety risk of gas leakage and diffusion, while generating flue gas that pollutes the environment. In addition, oxide scale will still form on the surface of the heating zone at the end of the electrode rod. If the steel rod is not treated subsequently and is remelted, the oxygen content and oxide inclusions in the steel at the starting end will increase, requiring a larger amount of material to be removed later, resulting in significant metal loss.

[0005] 3. Both traditional processes consume coal gas, posing environmental problems. Furthermore, using coal gas for baking on-site poses a safety risk of carbon monoxide poisoning.

[0006] Therefore, a special steel electroslag remelting consumable electrode rod end preheating device is needed to solve the problems of safety, environmental protection, low efficiency and high cost of traditional processes. Summary of the Invention

[0007] The purpose of this invention is to provide an end preheating device for a special steel electroslag remelting consumable electrode rod. This preheating device uses electric heating to preheat the end of the electroslag remelting consumable electrode rod, and has the advantages of simple structure, high efficiency and energy saving, safety and environmental protection, and convenient operation.

[0008] To achieve the above objectives, the present invention provides the following technical solution: A preheating device for the end of a special steel electroslag remelting consumable electrode rod is disclosed. The preheating device includes a preheating furnace body and a trolley. One end of the preheating furnace body is provided with an open preheating furnace opening. The preheating furnace body includes an outer shell and an inner cylinder. The inner cylinder is coaxially disposed inside the outer shell, and an electric heating wire is disposed on the inner wall of the inner cylinder. The preheating furnace body is placed horizontally on the trolley. Pushing the trolley can drive the preheating furnace body to move along the axial direction of the electroslag remelting consumable electrode rod. The movement of the preheating furnace body allows the end of the electroslag remelting consumable electrode rod to be preheated to enter the inner cylinder through the preheating furnace opening. When the electric heating wire is energized, it can preheat the end of the electroslag remelting consumable electrode rod.

[0009] Furthermore, in the aforementioned end preheating device for the special steel electroslag remelting consumable electrode rod, the outer shell is a cylindrical metal structure with one end open and the other end closed. An insulation layer is provided between the outer shell and the inner cylinder. The insulation layer is made of ceramic fiber and has a thickness of 150mm-250mm.

[0010] Furthermore, in the aforementioned preheating device for the end of the special steel electroslag remelting consumable electrode rod, the inner cylinder is composed of two semi-circular wire-wound refractory tubes and a furnace tail refractory plate. The two wire-wound refractory tubes, after being joined, form a cylindrical structure. The furnace tail refractory plate is fitted and fixed to the inner end face of the closed end of the outer shell. One end of each of the two wire-wound refractory tubes is connected to the furnace tail refractory plate. Both the furnace tail refractory plate and the wire-wound refractory tubes are made of high-temperature refractory materials. The inner wall of the wire-wound refractory tubes is uniformly arranged axially. There are several annular grooves that extend circumferentially along the refractory tube. Adjacent annular grooves are separated by a spacer. A groove is provided on the spacer along the axial direction of the inner cylinder, and adjacent annular grooves are connected by the groove. The heating wire is embedded and arranged along the entire path through the annular groove and the groove. The inlet and outlet ends of the heating wire are led out to the outside of the preheating furnace body through an insulating refractory tube. The inlet and outlet ends of the heating wire are connected to the control cabinet through wires.

[0011] Furthermore, in the aforementioned preheating device for the end of the special steel electroslag remelting consumable electrode rod, the control cabinet is equipped with a programmable heating curve. The control cabinet can adjust the heating rate and target temperature of the heating wire according to the material of the special steel. The diameter of the electroslag remelting consumable electrode rod is D mm, and the heating curve parameters are: heating rate of 30℃ / h~60℃ / h, holding temperature of 700℃~800℃, and holding time of D×1.5min / mm.

[0012] Furthermore, in the aforementioned preheating device for the end of the special steel electroslag remelting consumable electrode rod, an annular clamping steel ring is embedded inside the outer shell at the furnace opening of the preheating furnace. The clamping steel ring simultaneously covers the end face of the insulation layer and the wire-wound refractory tube near the furnace opening of the preheating furnace. The clamping steel ring is fastened to the outer shell by multiple sets of screws evenly distributed along the circumference.

[0013] Furthermore, in the aforementioned end preheating device for the special steel electroslag remelting consumable electrode rod, the inner diameter of the inner cylinder is more than 100 mm larger than the diameter of the electroslag remelting consumable electrode rod.

[0014] Furthermore, in the aforementioned end preheating device for the special steel electroslag remelting consumable electrode rod, two lifting lugs are provided at the upper end of the outer shell, and the overhead crane lifts the preheating furnace body through the lifting lugs.

[0015] Furthermore, in the aforementioned preheating device for the end of the special steel electroslag remelting consumable electrode rod, the trolley includes support legs, a base plate, a fixed plate, a support plate, and a height adjusting screw. Four support legs are provided. The support plate, fixed plate, and base plate are arranged sequentially from top to bottom. The upper ends of all four support legs are connected to the lower surface of the support plate. The fixed plate and base plate are respectively connected to the four support legs. Two bases are provided at the bottom of the preheating furnace body, arranged sequentially along the axial direction of the preheating furnace body. Each base is connected to a crossbeam via a fixing screw. The axis of the crossbeam is perpendicular to the axis of the preheating furnace body. The lower surface of the crossbeam has an installation groove. The height adjusting screw passes sequentially from bottom to top through the fixed plate and the support plate and extends into the installation groove of the crossbeam. Each crossbeam has two corresponding height adjusting screws. By sequentially turning the height adjusting screws, the horizontal height of the two crossbeams can be adjusted, achieving the alignment of the electroslag remelting consumable electrode rod with the axis of the inner cylinder.

[0016] Furthermore, in the aforementioned end preheating device for the special steel electroslag remelting consumable electrode rod, the lower ends of the four supporting legs of the trolley are respectively connected to wheels, two of which are omnidirectional wheels and the other two are directional wheels. Each wheel is equipped with a brake pad. The rear end of the trolley is symmetrically provided with two push-pull rods and push-pull handles. The lower ends of the push-pull rods are connected to the base plate and the fixing plate, and the upper ends of the push-pull rods extend upward and away from the trolley. The upper ends of the two push-pull rods are connected through the push-pull handles.

[0017] Furthermore, in the aforementioned end preheating device for the special steel electroslag remelting consumable electrode rod, the electroslag remelting consumable electrode rod to be preheated is placed on a support platform, and the length of the end of the electroslag remelting consumable electrode rod extending beyond the support platform is more than 200mm longer than the preset preheating length of the electroslag remelting consumable electrode rod; wedges are respectively provided on both sides of the contact position between the electroslag remelting consumable electrode rod and the support platform.

[0018] Analysis reveals that this invention discloses an end preheating device for a special steel electroslag remelted consumable electrode rod. This preheating device uses electric heating to preheat the end of the electroslag remelted consumable electrode rod. The control cabinet controls the heating temperature and rate according to the heating curve, preventing the electroslag remelted consumable electrode rod from cracking due to excessively rapid heating and resulting in chipping. Compared to gas annealing or gas baking, this preheating device avoids gas poisoning and environmental pollution, significantly reduces investment costs, and improves production efficiency; it is ready for immediate use after heating. The height of the preheating furnace body is adjustable using a trolley, facilitating the alignment of the electroslag remelted consumable electrode rod with the inner cylinder axis. It can accommodate platforms of different heights. The trolley, equipped with brake pads, allows for single-person operation of all movement, alignment, and loading, simplifying and accelerating the process and overcoming the spatial limitations of traditional fixed heating stations. Attached Figure Description

[0019] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Wherein: Figure 1 This is a schematic diagram of the structure of an electrode rod during end preheating according to an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the left-side structure according to an embodiment of the present invention.

[0021] Figure 3 This is a schematic cross-sectional view of a preheating furnace body according to an embodiment of the present invention.

[0022] Figure 4 This is a schematic diagram of the structure of a vehicle according to an embodiment of the present invention.

[0023] Figure 5 This is a schematic diagram of the cross-sectional structure of the inner cylinder according to an embodiment of the present invention.

[0024] Explanation of reference numerals in the attached drawings: 1. Electroslag remelting consumable electrode rod; 2. Shelf; 3. Ground; 4. Trolley; 5. Preheating furnace body; 6. Control cabinet; 7. Wire; 41. Push-pull handrail; 42. Support plate; 43. Height adjustment screw; 44. Brake pad; 45. Directional wheel; 46. Universal wheel; 48. Fixing screw; 49. Fixing plate; 410. Push-pull rod; 101. Outer shell; 102. Insulation layer; 103. Wire-wound refractory tube; 104. Furnace tail refractory plate; 105. Electrically insulating refractory tube; 106. Inlet terminal; 107. Outlet terminal; 108. Heating wire; 109. Preheating furnace opening; 110. Pressing steel ring; 111. Screw; 112. Lifting lug; 113. Base; 114. Spacer; 115. Groove; 116. Inlet hole; 117. Outlet hole; 118. Annular groove; 119. Crossbeam; 120. Fixing block; 121. Base plate; 122. Support leg. Detailed Implementation

[0025] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Various examples are provided by way of explanation and not by way of limitation. Indeed, those skilled in the art will recognize that modifications and variations can be made to the invention without departing from its scope or spirit. For example, a feature shown or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desirable that the invention encompass such modifications and variations falling within the scope of the appended claims and their equivalents.

[0026] In the description of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected," "linked," and "set up" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a direct connection or an indirect connection through intermediate components; a wired connection, a radio connection, or a wireless communication signal connection. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0027] The accompanying drawings illustrate one or more examples of the invention. The detailed description uses numerals and letters to refer to features in the drawings. Similar or analogous reference numerals in the drawings and description have been used to refer to similar or analogous parts of the invention. As used herein, the terms “first,” “second,” and “third,” etc., are used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of individual components.

[0028] To achieve the above objectives, the present invention provides the following technical solution: A preheating device for the end of a special steel electroslag remelting consumable electrode rod is disclosed. The preheating device consists of a circular preheating furnace body 5 and a liftable and adjustable trolley 4. The preheating furnace body 5 has three layers: the outermost layer is a metal shell 101, the middle layer is an insulation layer 102, and the inner layer is an inner cylinder made of high-temperature refractory material. The inner wall of the inner cylinder is provided with interconnected annular grooves 118. A set of annularly arranged heating wires 108 are provided on the inner wall of the preheating furnace body 5. The heating wires 108 are connected to the power supply of an external control cabinet 6. One end of the preheating furnace body 5 is open to facilitate the entry and exit of one end of the electroslag remelting consumable electrode rod 1 for baking, and the other end of the preheating furnace body 5 is closed.

[0029] a. The preheating device is equipped with a trolley 4, on which a preheating furnace body 5 is mounted. The trolley 4 and the preheating furnace body 5 are connected by screws, and the preheating furnace body 5 can be fixed. b. The lower end of the trolley 4 is equipped with 4 wheels, including 2 omnidirectional wheels 46, which have a braking function to ensure that the wheels can move and rotate on the ground and can stop moving when they reach the designated position. The other 2 directional wheels 45 have a braking function to ensure that the wheels can move on the ground and can stop moving when they reach the designated position. There is a push-pull handle 41 on the rear side of the upper part of the trolley 4.

[0030] c. The trolley 4 is equipped with a device for fine-tuning the lifting of the preheating furnace body 5; d. The preheating furnace body 5 is designed with three layers. The outermost layer is a metal shell 101 with lifting lugs 112. The middle layer is an insulation layer 102. The inner layer is an inner cylinder made of high-temperature refractory material (composed of two symmetrical halves of wire-wound refractory tubes 103, which is convenient to manufacture). In order to prevent the surface of the electroslag remelting consumable electrode rod 1 from contacting the inner surface of the preheating furnace body 5, the inner diameter of the inner cylinder is designed to be more than 100 mm larger than the electroslag remelting consumable electrode rod 1 to be baked. There are interconnected annular grooves 118 on the inner wall of the inner cylinder. A set of annularly arranged heating wires 108 are set on the inner wall of the preheating furnace body 5. The heating wires 108 are connected to the control cabinet of the external power supply. One end of the preheating furnace body 5 is open to facilitate the entry and exit of one end of the electroslag remelting consumable electrode rod 1 for baking. The other end of the preheating furnace body 5 is closed.

[0031] e. The external power supply control cabinet 6 can be set with a heating curve, and the heating rate and temperature can be controlled according to the heating curve.

[0032] Implemented process flow: 1. Hoist the special steel electroslag remelting consumable electrode rod 1 to the baking stand 2, place it stably, with the preheating end of the electroslag remelting consumable electrode rod 1 facing the preheating device. The length of the preheating end of the rod extending beyond the edge of the baking stand 2 must be more than 200mm longer than the preheating length. To prevent the electroslag remelting consumable electrode rod 1 from rolling, wedges are used on both sides of the contact point between the electroslag remelting consumable electrode rod 1 and the baking stand 2. The preheating length is marked on the preheating end of the electroslag remelting consumable electrode rod 1 with a marker.

[0033] 2. Manually push the trolley 4 equipped with the preheating device to the preheating end of the electroslag remelting consumable electrode rod 1, with its opening facing the steel rod. Adjust the height of the preheating furnace body 5, and make the outer surface of the electroslag remelting consumable electrode rod 1 basically consistent with the left and right distance of the inner edge of the preheating furnace opening 109, without contacting the inner surface of the preheating furnace body 5. After confirming the alignment, push the trolley 4 along the length of the rod, so that the preheating end of the electroslag remelting consumable electrode rod 1 enters the circular preheating furnace body 5. When the electroslag remelting consumable electrode rod 1 enters to the length marked by the pen on the rod, stop moving the trolley 4 and brake and fix the trolley 4.

[0034] 3. Turn on the power supply, set the heating curve, and slowly increase the temperature at 30℃ / h~60℃ / h. The holding temperature is 700℃~800℃ (depending on the steel grade). The holding time is equal to the bar diameter D (mm) x 1.5min / mm.

[0035] 4. After heating is complete, the system will automatically turn off the power.

[0036] 5. Manually release the trolley brake, move the trolley in the opposite direction to the end of the electroslag remelting consumable electrode rod 1, pull out the preheating end of the electroslag remelting consumable electrode rod 1, push the preheating furnace body 5 on the trolley 4 to transfer to the next electroslag remelting consumable electrode rod 1, and repeat the above process to preheat the next electroslag remelting consumable electrode rod 1.

[0037] 6. The overhead crane lifts the preheated electroslag remelting consumable electrode rod 1 and transfers it to the electroslag furnace for electroslag remelting.

[0038] Specific embodiments of the above technical solution are given below with reference to the accompanying drawings: like Figures 1 to 5 As shown, according to an embodiment of the present invention, an end preheating device for a special steel electroslag remelting consumable electrode rod is provided, such as... Figure 1As shown, the preheating device includes a preheating furnace body 5 and a trolley 4. One end of the preheating furnace body 5 has an open preheating furnace opening 109. The preheating furnace body 5 includes an outer shell 101 and an inner cylinder. The inner cylinder is coaxially disposed inside the outer shell 101, and heating wires 108 are installed on the inner wall of the inner cylinder. The preheating furnace body 5 is placed horizontally on the trolley 4. Pushing the trolley 4 can move the preheating furnace body 5 along the axial direction of the electroslag remelting consumable electrode rod 1. This movement of the preheating furnace body 5 allows the end of the electroslag remelting consumable electrode rod 1 to be preheated to enter the inner cylinder through the preheating furnace opening 109. When the heating wires 108 are energized, the end of the electroslag remelting consumable electrode rod 1 is preheated. This preheating device eliminates the need to move the heavy electroslag remelting consumable electrode rod 1 to complete the furnace loading operation, significantly reducing the difficulty of the operation. The preheating device preheats the end of the electroslag remelted consumable electrode rod 1 in offline mode. Multiple electroslag remelted consumable electrode rods 1 can be continuously heated by the moving trolley 4, which greatly improves the working efficiency, saves the floor space, requires less equipment investment, and does not require the use of an electroslag working site.

[0039] Furthermore, such as Figure 2 As shown, the outer shell 101 is a cylindrical metal structure that is open at one end and closed at the other. A heat insulation layer 102 is provided between the outer shell 101 and the inner cylinder. The heat insulation layer 102 is made of ceramic fiber and has a thickness of 150mm to 250mm. The heat insulation layer 102 can effectively reduce the loss of heat from the furnace to the external environment and improve the heat utilization efficiency.

[0040] Furthermore, such as Figure 5As shown, the inner cylinder is composed of two semi-circular wire-wound refractory tubes 103 and a furnace tail refractory plate 104 spliced ​​together. The two wire-wound refractory tubes 103 form a cylindrical structure after splicing. The furnace tail refractory plate 104 is attached and fixed to the inner end face of the closed end of the outer shell 101. One end of each of the two wire-wound refractory tubes 103 is connected to the furnace tail refractory plate 104. Both the furnace tail refractory plate 104 and the wire-wound refractory tubes 103 are made of high-temperature refractory materials. The inner wall of the wire-wound refractory tubes 103 is axially... A number of annular grooves 118 are evenly spaced and extend circumferentially along the refractory tube 103. Adjacent annular grooves 118 are separated by a spacer 114. A groove 115 is provided on the spacer 114 along the axial direction of the inner cylinder. Adjacent annular grooves 118 are connected by the groove 115 to form annular grooves 118 connected in series. The heating wire 108 is fully embedded and arranged through the annular grooves 118 and the grooves 115. The arrangement of the heating wire 108 is as follows: first, the first section of the heating wire 108 is inserted into the first annular groove 118 to complete the full circumference. Then, the transition section of the heating wire 108 is inserted into the groove 115 on the adjacent spacer 114 and extends into the next annular groove 118. This process is repeated to complete the wiring around all the annular grooves 118. The entire heating wire 108 is completely confined within the annular grooves 118 and grooves 115 of the wound refractory tube 103, ultimately forming a continuous serpentine fully embedded arrangement structure. This arrangement of the heating wire 108 can achieve uniform temperature distribution in the circumferential and axial directions within the preheating furnace body 5. The preheating furnace body 5 is provided with an inlet hole 116 and an outlet hole 117. An insulating refractory tube 105 is installed in both the inlet hole 116 and the outlet hole 117. The inlet end 106 of the heating wire 108 is led out to the outside of the preheating furnace body 5 through the insulating refractory tube 105 in the inlet hole 116, and the outlet end 107 of the heating wire 108 is led out to the outside of the preheating furnace body 5 through the insulating refractory tube 105 in the outlet hole 117. Both the inlet end 106 and the outlet end 107 of the heating wire 108 are connected to an external control cabinet 6 via wires 7. The external control cabinet 6 contains a power supply. The control cabinet 6 is equipped with a programmable heating curve, which can precisely adjust the heating rate and heating temperature of the heating wire 108 according to the material of the special steel, adapting to the preheating process requirements of special steels with different alloy compositions, and preventing the electroslag remelting consumable electrode rod 1 from shaving off due to excessively rapid heating and resulting end cracks. The diameter of the electroslag remelting consumable electrode rod 1 is D mm, and the heating curve parameters are: heating rate of 30℃ / h~60℃ / h, holding temperature of 700℃~800℃, and holding time of D×1.5min / mm.The preheating device uses two semi-circular wire-wound refractory tubes 103 and furnace tail refractory plate 104 to form an inner cylinder, which reduces the assembly difficulty of the inner cylinder. The heating wire 108 is embedded in the annular groove 118 of the inner cylinder to form a complete and continuous circuit, which can ensure that the current and voltage of the heating wire are synchronized throughout the process, making the temperature distribution in the cavity of the inner cylinder more uniform, and ultimately ensuring that the end of the electroslag remelting consumable electrode rod 1 is heated evenly.

[0041] Furthermore, an annular clamping steel ring 110 is embedded inside the outer shell 101 at the preheating furnace opening 109. The clamping steel ring 110 simultaneously covers the end faces of the insulation layer 102 and the wound refractory tube 103 near the preheating furnace opening 109. The clamping steel ring 110 is fastened to the outer shell 101 by multiple sets of screws 111 evenly distributed circumferentially. By clamping the insulation layer 102 and the wound refractory tube 103 with the clamping steel ring 110, it is possible to effectively prevent the insulation layer 102 and the wound refractory tube 103 from loosening and shifting under high-temperature operation.

[0042] Furthermore, the inner diameter of the inner cylinder is more than 100 mm larger than the diameter of the electroslag remelted consumable electrode rod 1 to prevent the end of the electroslag remelted consumable electrode rod 1 from contacting the inner surface of the inner cylinder when it enters the inner cylinder.

[0043] Furthermore, two lifting lugs 112 are provided at the upper end of the outer shell 101, and the overhead crane lifts the preheating furnace body 5 through the lifting lugs 112.

[0044] Furthermore, such as Figure 3 As shown, the trolley includes support legs 122, a base plate 121, a fixing plate 49, a support plate 42, and a height adjusting screw 43. Four support legs 122 are provided. The support plate 42, fixing plate 49, and base plate 121 are arranged sequentially from top to bottom. The upper ends of all four support legs 122 are connected to the lower surface of the support plate 42. The fixing plate 49 and base plate 121 are respectively connected to the four support legs 122. Figure 4As shown, two bases 113 are provided at the bottom of the preheating furnace body 5. The two bases 113 are arranged sequentially along the axial direction of the preheating furnace body 5. Each base 113 is detachably connected to a crossbeam 119 by a fixing screw 48, which facilitates the installation and maintenance of the preheating furnace body 5. The axis of the crossbeam 119 is perpendicular to the axis of the preheating furnace body 5. The height adjustment screw 43 passes through the fixing plate 49 and the support plate 42 from bottom to top and extends into the mounting groove of the crossbeam 119. The support plate 42 can provide support for the height adjustment screw 43. 3. Provides guidance. Each crossbeam 119 is equipped with two height adjustment screws 43. By turning the height adjustment screws in sequence, the horizontal height of the two crossbeams can be adjusted to achieve the alignment operation of the axis of the electroslag remelting consumable electrode rod and the inner cylinder. Multiple fixed blocks 120 are set on the base 113. The fixed blocks 120 are in contact with the outer wall of the bottom of the preheating furnace body 5. The fixed blocks 120 can limit the bottom of the preheating furnace body 5 to prevent the preheating furnace body 5 from sliding laterally during operation and transportation.

[0045] Furthermore, the lower ends of the four support legs 122 of the trolley 4 are respectively connected to wheels, two of which are omnidirectional wheels 46 and the other two are directional wheels 45. The two omnidirectional wheels 46 are located at the front of the trolley 4, and the two directional wheels 45 are located at the rear of the trolley 4. Each wheel is equipped with a brake pad 44. When the trolley 4 moves to the designated position, the brake pad 44 can lock the wheel to prevent the trolley 4 from moving. The rear end of the trolley 4 is symmetrically provided with two push-pull rods 410 and push-pull handles 41. The lower ends of the push-pull rods 410 are connected to the base plate 121 and the fixed plate 49. The upper ends of the push-pull rods 410 extend upward and away from the trolley 4. The upper ends of the two push-pull rods 410 are connected by the push-pull handles 41. The operator pushes the trolley 4 to move by pushing the handles 41, which is convenient and labor-saving.

[0046] Furthermore, the electroslag remelting consumable electrode rod 1 to be preheated is placed on the support platform 2, which is located on the ground 3. The length of the end of the electroslag remelting consumable electrode rod 1 extending out of the support platform 2 is more than 200mm longer than the preset preheating length of the electroslag remelting consumable electrode rod 1, ensuring that the area of ​​the electroslag remelting consumable electrode rod 1 to be preheated can be completely inserted into the preheating furnace body 5. Wedges are respectively set on both sides of the contact position between the electroslag remelting consumable electrode rod 1 and the support platform 2 to prevent the electroslag remelting consumable electrode rod 1 from rolling.

[0047] Compared with induction heating, this preheating device has lower equipment requirements, does not require a water cooling system, and can avoid the risk of water leakage and electric leakage.

[0048] The process flow for preheating the end of the electroslag remelted consumable electrode rod 1 using this preheating device is as follows: 1. Hoist the special steel electroslag remelting consumable electrode rod 1 onto the support platform 2 and place it stably. The preheating end of the electroslag remelting consumable electrode rod 1 should face the preheating device. Mark the preheating length on the preheating end of the electroslag remelting consumable electrode rod 1 with a marker.

[0049] 2. Manually push the trolley 4 equipped with the preheating device to the preheating end of the electroslag remelting consumable electrode rod 1, and align the preheating furnace opening 109 with the electroslag remelting consumable electrode rod 1. Adjust the height of the preheating furnace body 5 by adjusting the height adjusting screw 43 to achieve the alignment of the axis of the electroslag remelting consumable electrode rod 1 with the axis of the preheating furnace body 5, ensuring that the outer surface of the electroslag remelting consumable electrode rod 1 does not contact the inner surface of the preheating furnace body 5. After confirming the alignment, push the trolley 4 along the axis of the electrode rod so that the preheating end of the electroslag remelting consumable electrode rod 1 enters the preheating furnace body 5. Stop moving the trolley 4 when the electroslag remelting consumable electrode rod 1 enters to the marked line on the electrode rod and brake and fix the trolley 4.

[0050] 3. Start the control cabinet 6, set the heating curve, and the control cabinet 6 heats the end of the electroslag remelting consumable electrode rod 1 according to the heating curve. After the heating is completed, the control cabinet 6 automatically turns off the power.

[0051] 4. Manually release the brake pads 44 of the trolley 4, move the trolley 4 in the opposite direction to the end of the electroslag remelting consumable electrode rod 1, pull out the preheating end of the electroslag remelting consumable electrode rod 1, push the cylindrical preheating furnace on the trolley 4 to transfer to the next electroslag remelting consumable electrode rod 1, and repeat the above process to preheat the next electroslag remelting consumable electrode rod 1.

[0052] 5. The overhead crane lifts the preheated electroslag remelting consumable electrode rod 1 and transfers it to the electroslag furnace for electroslag remelting.

[0053] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects: 1. The preheating device uses electric heating to preheat the end of the electroslag remelted consumable electrode rod 1. The control cabinet 6 controls the heating temperature and heating rate according to the heating curve to prevent the end cracks of the electroslag remelted consumable electrode rod 1 from falling off due to excessive heating rate.

[0054] 2. Compared with gas annealing or gas baking, this preheating device can avoid the problems of gas poisoning and environmental pollution, greatly save investment costs, improve production efficiency, and can be used immediately after heating.

[0055] 3. The height of the preheating furnace body 5 is adjusted by using the trolley 4, which facilitates the alignment of the axis of the electroslag remelting consumable electrode rod 1 with the inner cylinder and can be adapted to the shelf 2 of different heights. 4. The trolley 4 with brake pads 44 is used, which can be pushed by a single person to complete all moving, centering and loading operations. The operation is simple and quick, and it gets rid of the space limitation of the traditional fixed heating station.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An end preheating device for a special steel electroslag remelting consumable electrode rod, characterized in that, The preheating device includes a preheating furnace body and a trolley. One end of the preheating furnace body is provided with an open preheating furnace opening. The preheating furnace body includes an outer shell and an inner cylinder. The inner cylinder is coaxially arranged inside the outer shell, and heating wires are arranged on the inner wall of the inner cylinder. The preheating furnace body is placed horizontally on the trolley. Pushing the trolley can drive the preheating furnace body to move along the axial direction of the electroslag remelted consumable electrode rod. The movement of the preheating furnace body can allow the end of the electroslag remelted consumable electrode rod to be preheated to enter the inner cylinder from the furnace opening of the preheating furnace. When the heating wire is energized, it can preheat the end of the electroslag remelted consumable electrode rod.

2. The end preheating device for the special steel electroslag remelting consumable electrode rod according to claim 1, characterized in that, The outer shell is a cylindrical metal structure that is open at one end and closed at the other end. An insulation layer is provided between the outer shell and the inner cylinder. The insulation layer is made of ceramic fiber and has a thickness of 150mm-250mm.

3. The end preheating device for the special steel electroslag remelting consumable electrode rod according to claim 2, characterized in that, The inner cylinder is composed of two semi-circular wire-wound refractory tubes and a furnace tail refractory plate. The two wire-wound refractory tubes are spliced ​​together to form a cylindrical structure. The furnace tail refractory plate is attached and fixed to the inner end face of the closed end of the outer shell. One end of each of the two wire-wound refractory tubes is connected to the furnace tail refractory plate. Both the furnace tail refractory plate and the wire-wound refractory tube are made of high-temperature refractory materials. A plurality of annular grooves are uniformly arranged along the axial direction on the inner wall of the wire-wound refractory tube. The annular grooves extend along the circumference of the wire-wound refractory tube. Adjacent annular grooves are separated by a spacer platform. A groove is provided on the spacer platform along the axial direction of the inner cylinder. Adjacent annular grooves are connected by the groove. The heating wire is fully embedded and arranged through the annular groove and the recess. The inlet and outlet ends of the heating wire are led out to the outside of the preheating furnace body through insulated refractory tubes. Both the inlet and outlet ends of the heating wire are connected to the control cabinet through wires.

4. The end preheating device for the special steel electroslag remelting consumable electrode rod according to claim 3, characterized in that, The control cabinet is equipped with a programmable heating curve, and the control cabinet can adjust the heating rate and target temperature of the heating wire according to the material of the special steel. The diameter of the electroslag remelting consumable electrode rod is D mm, and the heating curve parameters are: heating rate of 30℃ / h~60℃ / h, holding temperature of 700℃~800℃, and holding time of D×1.5min / mm.

5. The end preheating device for the special steel electroslag remelting consumable electrode rod according to claim 3, characterized in that, An annular clamping steel ring is embedded inside the outer shell at the furnace opening of the preheating furnace. The clamping steel ring covers both the insulation layer and the end face of the wire-wound refractory tube near the furnace opening of the preheating furnace. The clamping steel ring is fastened to the outer shell by multiple sets of screws evenly distributed along the circumference.

6. The end preheating device for the special steel electroslag remelting consumable electrode rod according to claim 1, characterized in that, The inner diameter of the inner cylinder is more than 100 mm larger than the diameter of the electroslag remelted consumable electrode rod.

7. The end preheating device for the special steel electroslag remelting consumable electrode rod according to claim 1, characterized in that, Two lifting lugs are provided at the upper end of the outer shell, and the overhead crane lifts the preheating furnace body through the lifting lugs.

8. The end preheating device for the special steel electroslag remelting consumable electrode rod according to claim 1, characterized in that, The trolley includes support legs, a base plate, a fixed plate, a support plate, and a height adjustment screw. There are four support legs. The support plate, the fixed plate, and the base plate are arranged in order from top to bottom. The upper ends of the four support legs are all connected to the lower surface of the support plate. The fixed plate and the base plate are respectively connected to the four support legs. Two bases are provided at the bottom of the preheating furnace body, and the two bases are arranged sequentially along the axial direction of the preheating furnace body. Each base is connected to a crossbeam by a fixing screw. The axis of the crossbeam is perpendicular to the axis of the preheating furnace body. The lower surface of the crossbeam is provided with a mounting groove. The height adjustment screw passes through the fixing plate and the support plate from bottom to top and extends into the mounting groove of the crossbeam. Each crossbeam is provided with two height adjustment screws. By turning the height adjustment screws sequentially, the horizontal height of the two crossbeams can be adjusted to achieve the alignment operation of the electroslag remelting consumable electrode rod with the axis of the inner cylinder.

9. The end preheating device for the special steel electroslag remelting consumable electrode rod according to claim 1, characterized in that, The lower ends of the four support legs of the trolley are respectively connected to wheels, two of which are omnidirectional wheels and the other two are directional wheels. Each of the aforementioned wheels is equipped with a brake pad at the wheel body position. The rear end of the trolley is symmetrically provided with two push-pull rods and push-pull handrails. The lower end of the push-pull rods is connected to the base plate and the fixed plate, and the upper end of the push-pull rods extends upward and away from the trolley. The upper ends of the two push-pull rods are connected by the push-pull handrails.

10. The end preheating device for the special steel electroslag remelting consumable electrode rod according to claim 1, characterized in that, The electroslag remelted consumable electrode rod to be preheated is placed on a support platform, and the length of the end of the electroslag remelted consumable electrode rod extending out of the support platform is more than 200 mm longer than the preset preheating length of the electroslag remelted consumable electrode rod. Wedges are provided on both sides of the contact position between the electroslag remelting consumable electrode rod and the support platform.

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