A high-efficiency steel rolling heating furnace and working method thereof

Abstract

The present invention discloses a high-efficiency steel rolling heating furnace, comprising a conveying support, a continuous induction furnace body and a temperature sensor. The continuous induction furnace body comprises a low-temperature section, a high-temperature section and a heat preservation section which are continuously arranged in the middle position of the conveying support; the low-temperature section comprises a shell, an induction body, a casting layer and a supporting inner core, the casting layer is cast and formed on the inner wall of the shell, the induction body is buried in the casting layer and the two ends protrude from the shell to connect the induction power supply and the cooling system; the supporting inner core is detachably installed in the middle square hole of the casting layer, the bottom of the supporting inner core groove is provided with a bottom wheel and the side wall of the groove is provided with a side wheel, the bottom wheel and the side wheel roll in contact with the steel billet to be heated; the structural form of the high-temperature section and the heat preservation section is consistent with that of the low-temperature section; the temperature sensor collects the temperature signal of the steel billet surface and feeds it back to the equipment control system. The present invention also discloses a working method of a steel rolling heating furnace. The three-stage continuous induction furnace body is used to heat the steel billet, which improves the heating efficiency and has good uniformity of temperature increase of the steel billet.

Description

Technical Field

[0001] The invention relates to the technical field of steel rolling heating equipment, and in particular to a high-efficiency steel rolling heating furnace and a working method thereof. Background Art

[0002] In the metallurgical steel industry, when the core of the continuous casting billet is to be completely crystallized after continuous casting, the outer surface temperature must be no less than 850°C, otherwise it cannot be directly rolled into the rolling mill. The outer surface temperature of the billet must be raised to about 1000°C, and the temperature inside and outside the billet must be balanced to achieve a relatively stable metal structure to meet the rolling process requirements of various steel grades. For the secondary heating of the billet, a new type of medium frequency induction heating furnace has now appeared to replace the traditional heating furnace that burns fuel. The medium frequency induction heating furnace generally includes an induction heating system, an induction power supply, a conveying system, a cooling system and a control system. The medium frequency induction heating furnace has the advantages of fast equipment heating speed, high temperature control accuracy, high energy utilization, energy saving and environmental protection, and easy automatic control, and has been increasingly used.

[0003] However, the induction heating system of the existing medium frequency induction heating furnace often adopts a method of arranging multiple groups separately on the conveying line, and induction heating is performed on the passing billets in sequence during the conveying process of the billets. The utility model patented induction heating furnace with announcement number CN210030827U and the utility model patented tunnel-type electromagnetic induction billet heating furnace with announcement number CN201753362U both adopt a method of arranging multiple groups of induction heating furnace bodies separately, and conveying rollers for conveying billets are arranged between two adjacent groups of induction heating furnace bodies. Although this arrangement method can ensure that shorter billets can pass smoothly through the narrower induction heating furnace body, this separate arrangement will also cause the billets to cool down when being conveyed between adjacent induction heating furnace bodies, resulting in reduced heating efficiency, and will also cause uneven temperature rise of the billets, which is not conducive to rolling.

[0004] Therefore, it is necessary to develop a high-efficiency steel rolling heating furnace and a working method thereof. Summary of the invention

[0005] The purpose of the present invention is to provide a high-efficiency steel rolling heating furnace, which adopts a three-stage continuous induction furnace body to heat the steel billet, thereby improving the heating efficiency and achieving good uniformity in the temperature increase of the steel billet.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] The present invention discloses a high-efficiency steel rolling heating furnace, comprising a conveying support, a continuous induction furnace body and a temperature sensor, wherein the continuous induction furnace body comprises a low-temperature section, a high-temperature section and a heat-insulating section which are continuously connected from front to back at the middle position of the conveying support; the low-temperature section comprises a shell, an induction body, a casting layer and a supporting inner core, the shell is a rectangular shell made of non-magnetic conductive material, and square holes for materials to pass through are arranged on both end surfaces of the rectangular shell; the casting layer is cast and formed on the inner wall of the shell by using refractory castables, the induction body is buried in the casting layer and its two ends protrude out of the shell to connect with an induction power supply and a cooling system; The supporting inner core can be detachably installed at the lower part of the middle square hole of the casting layer, the cross-section of the supporting inner core is U-shaped, a plurality of bottom wheels are arranged at the bottom of the supporting inner core groove, a plurality of side wheels are arranged at the side wall of the groove of the supporting inner core, the bottom wheels and the side wheels roll in contact with the bottom and side surfaces of the steel billet that need to be heated; the structural form of the high temperature section and the heat preservation section is consistent with that of the low temperature section, except that the configuration parameters of the induction body are different; the number of the temperature sensors is three and they are respectively arranged at the discharge ends of the low temperature section, the high temperature section and the heat preservation section, and the temperature sensors collect the temperature signal of the steel billet surface and feed it back to the equipment control system.

[0008] Furthermore, the low-temperature section is provided with a docking flange edge at one end facing the high-temperature section, the high-temperature section is provided with docking flange edges at both ends, and the insulation section is provided with a docking flange edge at one end facing the high-temperature section, and the three are detachably connected together through the docking flange edges.

[0009] Furthermore, the conveying bracket is provided with a front conveying roller on the front side of the low-temperature section, and the conveying bracket is provided with a rear conveying roller on the rear side of the insulation section. The top edges of the front conveying roller and the rear conveying roller are flush with the top edge of the bottom wheel; the front conveying roller and the rear conveying roller are both driven by a controllable servo motor.

[0010] Furthermore, it also includes a protective gas input mechanism, which includes a gas source, a valve group and an air pipe joint. The air pipe joint is arranged on the cylinder wall of the high-temperature section, and the inner end of the air pipe joint is connected to the inner cavity of the high-temperature section; the gas source supplies protective gas to the air pipe joint through the valve group.

[0011] Furthermore, the air pipe joint includes a pipe joint body, an external thread section, an air nozzle and a lock nut. The input end of the pipe joint body passes through the through hole on the top wall of the high-temperature section shell and is threadedly connected to the external thread section by the lock nut for locking. The protruding end of the external thread section is connected to the pipeline of the valve group; the two air nozzles are forked and connected and arranged at the output end of the pipe joint body, and the two air nozzles are respectively arranged toward the low-temperature section and the insulation section.

[0012] Furthermore, it also includes an auxiliary pushing mechanism arranged above the front conveying roller, the auxiliary pushing mechanism includes an action cylinder, a cylinder support, a connecting plate, a guide rod and a pushing assembly, the action cylinder is horizontally arranged above the front conveying roller and is connected to the raising support frame of the conveying bracket through the cylinder support at the end; the piston rod of the action cylinder faces the low-temperature section and the end is connected to the connecting plate, the bottom end of the connecting plate is connected to the guide rod below, and the end of the guide rod facing the feeding direction is connected to the pushing assembly, and the pushing assembly can assist in pushing the steel billet through the continuous induction furnace body.

[0013] Furthermore, the pushing assembly includes a fixed block and a movable pushing block, the vertical plate of the fixed block is locked on the end of the guide rod by a nut, the bottom plate of the fixed block is connected to the movable pushing block by a pin shaft at one end toward the low-temperature section, and a pad is provided at one end of the bottom plate of the fixed block away from the pin shaft; when the top plate of the movable pushing block contacts the pad block, the vertical plate of the movable pushing block is in a vertical position and can contact the rear end face of the billet.

[0014] Furthermore, it also includes a belt conveyor mechanism, which includes a driving roller, a conveyor belt, and a driven roller. The driving roller is arranged between the outlet of the insulation section and the rear conveyor roller, and the driven roller is arranged between the inlet of the low-temperature section and the front conveyor roller. The conveyor belt is transmission-connected between the driving roller and the driven roller, and the upper half of the conveyor belt covers the bottom wheel.

[0015] Furthermore, the belt conveyor mechanism also includes a tensioning wheel, a transfer wheel, a tensioning bracket, an auxiliary material supply box and a tension spring. The tensioning bracket is connected to the lower part of the conveying bracket through a pin shaft in the middle. The working end of the tensioning bracket is installed with a tensioning wheel and a transfer wheel that are split and meshed. The tensioning wheel is pressed against the conveyor belt, and the transfer wheel can dip the coating material from the auxiliary material supply box. The tension spring is tightened at the other end of the tensioning bracket.

[0016] The invention also discloses a working method of a steel rolling heating furnace, which adopts a continuous induction furnace body to carry out segmented temperature increase on a steel billet to be heated so as to meet the rolling requirements.

[0017] Compared with the prior art, the beneficial technical effects of the present invention are:

[0018] The present invention discloses an efficient steel rolling heating furnace, which is provided with a continuous induction furnace body composed of a low temperature section, a high temperature section and a heat preservation section, and adopts a segmented continuous induction heating method. Compared with the existing open group heating, it reduces the heat loss in the heat transfer process, can improve the heating efficiency, and ensure the uniformity of heating of the steel billet to facilitate subsequent rolling. By arranging a supporting inner core in each furnace body section, and arranging a bottom wheel and a side wheel on the supporting inner core, the steel billet passing through the longer continuous induction furnace body can be supported and assisted in transportation. The supporting inner core can be detachably installed in the middle square hole of the casting layer, which is convenient for partial replacement after damage occurs, avoiding the overall replacement of the furnace body, and reducing the maintenance and repair costs. The present invention discloses an efficient steel rolling heating furnace, which adopts a three-stage continuous induction furnace body to heat the steel billet, improves the heating efficiency, and has good uniformity in the temperature increase of the steel billet.

[0019] In addition, the low temperature section, high temperature section and insulation section connected together by flange butt joint are easy to assemble and disassemble, which is conducive to later maintenance and replacement. By setting the protective gas input mechanism, the protective nitrogen is input into the tunnel cavity of the continuous induction furnace body, which can reduce the oxidation of the surface of the steel billet during the heating process and reduce the oxidation loss; the air pipe joint is set on the shell in the middle of the high temperature section, and the two bifurcated air nozzles are discharged on both sides, and the nitrogen flows from the middle to the two ends. The density of nitrogen is close to that of air, and under the condition of small flow, it can effectively prevent air from entering the furnace body cavity from both ends. By setting the action cylinder, connecting plate, guide rod and pushing assembly, auxiliary pushing can be performed when the short steel billet is difficult to transport, avoiding the situation of transportation jam or large speed difference; by using the guide rod as an intermediate transmission member, it can save the installation longitudinal space, increase the installation height of the action cylinder, reduce the influence of heat radiation, and reduce the heat transfer to the piston rod. By setting a conveyor belt throughout the length of the continuous induction furnace body, a power transmission can be formed in the cavity of the continuous induction furnace body, thereby reducing the restriction on the length of the steel billet; by covering the bottom wheel with the conveyor belt, the friction resistance during the transportation process can be reduced. The coating material is dipped into the transfer wheel and transferred to the tensioning wheel. The tensioning wheel brushes the coating material on the outer ring surface of the conveyor belt while tensioning the conveyor belt. The coating material can effectively prevent the steel billet from being thermally bonded due to long-term contact with the conveyor belt, ensuring the normal transportation of the conveyor belt. The setting of the auxiliary material recovery component can recover the coating material that falls during the turning of the conveyor belt. At the same time, the setting of the felt brush and the cylinder can clean up the small amount of coating material adhering to the lower surface of the steel billet to avoid entering the rolling process.

[0020] The working method of the steel rolling heating furnace of the present invention adopts a segmented continuous heating method, which can accurately and reliably control the heating temperature of the steel billet and reduce unnecessary heat loss; by introducing nitrogen protective gas, the oxidation loss in the heating process of the steel billet can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below in conjunction with the accompanying drawings.

[0022] Figure 1 This is a schematic diagram of the main structure of Example 1 of a high-efficiency steel rolling heating furnace of the present invention;

[0023] Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure of the middle AA part;

[0024] Figure 3 for Figure 1 A schematic diagram of the partial cross-sectional structure of the middle I part;

[0025] Figure 4 This is a schematic diagram of the main structure of Example 2 of a high-efficiency steel rolling heating furnace of the present invention;

[0026] Figure 5 This is a schematic diagram of the structure of the material pushing component of the embodiment 2 of the high-efficiency steel rolling heating furnace of the present invention;

[0027] Figure 6 This is a schematic diagram of the main structure of Example 3 of the high-efficiency steel rolling heating furnace of the present invention.

[0028] Description of the accompanying drawings: 1. conveying bracket; 101. front conveying roller; 102. support beam; 103. rear conveying roller; 2. low temperature section; 3. high temperature section; 4. insulation section; 5. butt flange; 6. temperature sensor; 7. air pipe joint; 701. external thread section; 702. air nozzle; 703. lock nut; 8. induction body; 9. casting layer; 10. support inner core; 11. bottom wheel; 12. side wheel; 13. steel billet; 14. Action cylinder; 15, cylinder support; 151, guide sleeve; 16, connecting plate; 17, guide rod; 18, fixed block; 181, cushion block; 19, movable push block; 191, back rib plate; 20, pin shaft; 21, active roller; 22, conveyor belt; 23, driven roller; 24, tensioning wheel; 25, transfer wheel; 26, tension spring; 27, auxiliary material supply box; 28, proximity switch; 29, felt brush; 30, cylinder; 31, auxiliary material recovery box. DETAILED DESCRIPTION

[0029] The core of the present invention is to provide a high-efficiency steel rolling heating furnace and a working method thereof, which adopts a three-stage continuous induction furnace body to heat the steel billet, thereby improving the heating efficiency and achieving good uniformity in the temperature increase of the steel billet.

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0032] With reference to the accompanying drawings, Figure 1 This is a schematic diagram of the main structure of Example 1 of a high-efficiency steel rolling heating furnace of the present invention; Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure of the middle AA part; Figure 3 for Figure 1 A schematic diagram of the partial cross-sectional structure of the middle I part; Figure 4 This is a schematic diagram of the main structure of Example 2 of a high-efficiency steel rolling heating furnace of the present invention; Figure 5 This is a schematic diagram of the structure of the material pushing component of the embodiment 2 of the high-efficiency steel rolling heating furnace of the present invention; Figure 6 This is a schematic diagram of the main structure of Example 3 of the high-efficiency steel rolling heating furnace of the present invention.

[0033] Example 1

[0034] like Figures 1 to 3As shown, a high-efficiency steel rolling heating furnace comprises a conveying support 1, a continuous induction furnace body and a temperature sensor 6. The continuous induction furnace body comprises a low-temperature section 2, a high-temperature section 3 and a heat preservation section 4 which are continuously connected from front to back at the middle position of the conveying support 1. The low-temperature section 2 comprises a shell, an induction body 8, a casting layer 9 and a support inner core 10. The shell is a rectangular shell made of non-magnetic conductive material. The two end surfaces of the rectangular shell are provided with square holes for the steel billet 13 to pass through. The casting layer 9 is cast on the inner wall of the shell by using refractory castables. The induction body 8 is buried in the casting layer 9 and the two ends extend out of the shell to connect the induction power supply and the cooling system. The induction body 8 is an induction coil formed by bending a copper tube. The support inner core 10 is installed at the lower part of the middle square hole of the casting layer 9 by ceramic bolts. The cross section of the support inner core 10 is a U-shaped with an opening facing upward, that is, a groove is opened on the top surface. A plurality of bottom wheels 11 are provided at the bottom of the groove of the support inner core 10. The bottom of the bottom wheel 11 is at least two rows extending along the length direction of the material conveying. The side wall of the groove supporting the inner core 10 is provided with a plurality of side wheels 12, and a row of side wheels 12 are respectively provided on the side walls of the two grooves and extend along the length direction of the material conveying. The bottom wheel 11 and the side wheel 12 are both made of high temperature resistant ceramic materials. The bottom wheel 11 and the side wheel 12 respectively roll and contact the bottom and side of the steel billet 13 to be heated. The structural form of the high temperature section 3 and the insulation section 4 is consistent with the low temperature section 2, but the configuration parameters and length of the induction body 8 are different, and thus the heating temperature is different. There are three temperature sensors 6 and they are respectively arranged at the discharge ends of the low temperature section 2, the high temperature section 3 and the insulation section 4. The temperature sensor 6 adopts a non-contact infrared temperature sensor. The temperature sensor 6 collects the temperature signal of the surface of the steel billet 13 and feeds it back to the equipment control system. In a specific embodiment, the feedback temperature of the low temperature section 2 is controlled at 850±5℃, the feedback temperature of the high temperature section 3 is controlled at 980±5℃, and the feedback temperature of the insulation section 4 is controlled at 1000±3℃. The control system adopts PLC closed-loop control of the output power of the induction body 8. Of course, the controlled temperature of each section can be adaptively adjusted according to the specifications and types of the rolled steel billet.

[0035] The continuous induction furnace body consisting of the low temperature section 2, the high temperature section 3 and the insulation section 4 is set up, and the segmented continuous induction heating method is adopted. Compared with the existing open group heating, the heat loss in the heat transfer process is reduced, the heating efficiency can be improved, and the uniformity of the heating of the steel billet is ensured to facilitate the subsequent rolling. By setting the support inner core 10 in each furnace body section, and setting the bottom wheel 11 and the side wheel 12 on the support inner core 10, the steel billet 13 passing through the long continuous induction furnace body can be supported and assisted in transportation. The support inner core 10 can be detachably installed in the middle square hole of the casting layer 9, which is convenient for partial replacement after damage, avoiding the replacement of the furnace body as a whole, and reducing the maintenance cost.

[0036] Specifically, if Figure 1As shown, the low temperature section 2 is provided with a butt flange 5 at one end facing the high temperature section 3, butt flanges 5 are provided at both ends of the high temperature section 3, and the insulation section 4 is provided with a butt flange 5 at one end facing the high temperature section 3. The butt flange 5 is integrally formed with the shell of each furnace section or connected by root welding. The three are detachably connected together by non-metallic bolts of the butt flange 5.

[0037] The low temperature section 2, the high temperature section 3 and the heat preservation section 4 connected together by flange edge docking are easy to assemble and disassemble, which is beneficial to later maintenance and replacement.

[0038] Specifically, if Figure 1 and Figure 2 As shown, the conveying bracket 1 is provided with a front conveying roller 101 at the front side of the low temperature section 2, and the conveying bracket 1 is provided with a rear conveying roller 103 at the rear side of the insulation section 4, and the top edges of the front conveying roller 101 and the rear conveying roller 103 are flush with the top edge of the bottom wheel 11. The front conveying roller 101 and the rear conveying roller 103 are both driven by controllable servo motors, and the control system can control the rotation speed of the front conveying roller 101 and the rear conveying roller 103, thereby controlling the conveying speed of the steel billet 13. Furthermore, the conveying bracket 1 is provided with a support beam 102 below the continuous induction furnace body, which supports the low temperature section 2, the high temperature section 3 and the insulation section 4 respectively.

[0039] The front conveying roller 101 and the rear conveying roller 103 are arranged to cooperate with the bottom wheel 11 of the continuous induction furnace body to convey the steel billet 13. By adopting the servo motor drive mode, it is convenient to control the conveying speed of the steel billet 13.

[0040] In a specific implementation of this embodiment, Figure 1 and Figure 3 As shown, the high-efficiency steel rolling heating furnace of the present invention also includes a protective gas input mechanism, which includes a gas source, a valve group and a gas pipe joint 7. The gas pipe joint 7 is arranged on the cylinder wall of the high-temperature section 3, and the inner end of the gas pipe joint 7 is connected to the inner cavity of the high-temperature section 3. The gas source supplies protective gas to the gas pipe joint 7 through the valve group. The protective gas specifically uses nitrogen, and the gas source is a gas cylinder filled with nitrogen. The valve group includes an electric control valve and a flow valve. The flow valve is adjusted to control the supply of nitrogen. The nitrogen supply flow rate can be controlled at 2 to 4 L / Min during normal operation.

[0041] Specifically, if Figure 3As shown, the air pipe joint 7 includes a pipe joint body, an external thread section 701, an air nozzle 702 and a lock nut 703, and the air pipe joint 7 is made of non-magnetic material. The input end of the pipe joint body passes through the through hole on the top wall of the high temperature section 3 shell, and then the lock nut 703 is threadedly connected to the external thread section 701 for locking. The end of the external thread section 701 protrudes and connects to the air supply pipeline of the valve group. Two air nozzles 702 are arranged at the output end of the pipe joint body, and the two air nozzles 702 are arranged toward the low temperature section 2 and the insulation section 4 respectively.

[0042] By setting up a protective gas input mechanism, protective nitrogen is input into the tunnel cavity of the continuous induction furnace body, which can reduce the surface oxidation of the steel billet 13 during the heating process and reduce oxidation losses; the air pipe joint 7 is set on the shell in the middle of the high-temperature section 3, and two forked air nozzles 702 exhaust gas on both sides, and nitrogen flows from the middle to both ends. The density of nitrogen is close to that of air, and under the condition of small flow rate, it can effectively prevent air from entering the furnace body cavity from both ends.

[0043] When the length of the steel billet 13 is greater than twice the length of the continuous induction furnace body, it is particularly suitable to use the high-efficiency steel rolling heating furnace in this embodiment to perform secondary heating of the steel billet 13. During operation, the front conveying roller 101 moves the steel billet 13 that needs secondary heating from the low-temperature section 2 into the continuous induction furnace body. The continuous induction furnace body enters the working state according to the parameters set by the control system, and performs induction heating on the steel billet 13 entering the tunnel cavity. During this process, the steel billet 13 walks on the bottom wheel 11, and the side wheel 12 limits the side wall of the steel billet 13. When the steel billet 13 passes the tail end of the low-temperature section 2, the feedback temperature is controlled at 850°C; when passing the tail end of the high-temperature section 3, the feedback temperature is controlled at 980°C; when passing the tail end of the insulation section 4, the feedback temperature is controlled at 1000°C. At the same time, the air pipe joint 7 continuously sprays nitrogen, so that the air in the inner cavity of the continuous induction furnace body is discharged for atmosphere protection to reduce oxidation losses.

[0044] Example 2

[0045] When the length of the steel billet 13 is 1.5 to 2 times the length of the continuous induction furnace, the conveying method of the above embodiment 1 cannot ensure that the steel billet 13 is conveyed backward at a stable speed, which affects the heating quality. Based on the above embodiment 1, the conveying method of the steel billet 13 is improved to form this embodiment.

[0046] like Figure 4 and Figure 5As shown, the high-efficiency steel rolling heating furnace of the present invention also includes an auxiliary pushing mechanism arranged above the front conveying roller 101, and the auxiliary pushing mechanism includes an action cylinder 14, a cylinder support 15, a connecting plate 16, a guide rod 17 and a pushing assembly. The action cylinder 14 specifically adopts a hydraulic cylinder or a cylinder with a speed regulating valve, and the effective action stroke of the action cylinder 14 is half of the continuous induction furnace body. The action cylinder 14 is horizontally arranged above the front conveying roller 101 and is installed on the heightening support frame of the conveying bracket 1 through the cylinder support 15 at the end. The piston rod of the action cylinder 14 faces the low-temperature section 2 and the end is connected to the connecting plate 16. The bottom end of the connecting plate 16 is connected to the guide rod 17 below. The guide rod 17 is horizontally arranged below the action cylinder 14. One end of the guide rod 17 facing the feeding direction is connected to the pushing assembly, and the pushing assembly can assist in pushing the steel billet 13 through the continuous induction furnace body.

[0047] Specifically, if Figure 4 As shown, a guide sleeve 151 is further provided at the bottom of the cylinder support 15 , and the guide sleeve 151 is sleeved on the guide rod 17 to guide and support the guide rod 17 .

[0048] By setting the action cylinder 14, the connecting plate 16, the guide rod 17 and the pushing assembly, auxiliary pushing can be performed when the shorter billet 13 is difficult to transport, thereby avoiding transportation jams or large speed differences; by using the guide rod 17 as an intermediate transmission component, the longitudinal installation space can be saved, the installation height of the action cylinder 14 can be increased, the influence of heat radiation can be reduced, and the heat transfer to the piston rod can be reduced.

[0049] Specifically, if Figure 4 and Figure 5 As shown, the push assembly includes a fixed block 18 and a movable push block 19. The vertical plate of the fixed block 18 is locked on the end of the guide rod 17 by a nut. The bottom plate of the fixed block 18 is connected to the movable push block 19 by a pin 20 at one end facing the low-temperature section 2, and the movable push block 19 can swing around the pin 20. A cushion block 181 is welded on the bottom surface of the bottom plate of the fixed block 18 away from the pin 20. When the top plate of the movable push block 19 contacts the cushion block 181, the vertical plate of the movable push block 19 is in a vertical position and can contact the rear end surface of the billet 13. An inclined back rib plate 191 is welded between the back of the vertical plate of the movable push block 19 and the bottom surface of the top plate. The front end surface of the billet 13 conveyed from the front conveying roller 101 pushes the back rib plate 191 so that the movable push block 19 swings a certain angle and then passes through the top surface of the billet 13. After the billet 13 has completely passed through, the movable push block 19 swings backward and re-enters the vertical state, and under the pull of the guide rod 17, assists in pushing the billet 13 through the continuous induction furnace body.

[0050] By providing the fixed block 18 and the movable push block 19 , the swing of the movable push block 19 can avoid the conveyed steel billet 13 and reduce the upward transfer of heat.

[0051] During the conveying process of the steel billet 13 whose length is 1.5 to 2 times of the length of the continuous induction furnace body, when the high-efficiency steel rolling heating furnace of this embodiment is working, most of the steel billet 13 enters the cavity of the continuous induction furnace body, the rolling conveying force of the front conveying roller 101 is reduced, and the steel billet 13 continues to move forward and is stuck or the speed is reduced. The control system controls the action of the action cylinder 14, the piston rod of the action cylinder 14 is pushed out, and the guide rod 17 is driven to convey backward through the connecting plate 16, and the guide rod 17 drives the fixed block 18 and the movable push block 19, and the top plate of the movable push block 19 is pressed against the cushion block 181 and cannot swing backward. The movable push block 19 pushes the steel billet 13 to continue to move forward until the rear conveying roller 103 contacts the steel billet 13 of sufficient length and can be conveyed backward.

[0052] Example 3

[0053] When the length of the steel billet 13 is less than 1.5 of the length of the continuous induction furnace, the conveying methods of the above-mentioned embodiments 1 and 2 cannot ensure that the steel billet 13 is conveyed backward at a stable speed, which affects the heating quality. Based on the above-mentioned embodiment 1, the conveying method of the steel billet 13 is improved to form this embodiment.

[0054] like Figure 6 As shown, the high-efficiency steel rolling heating furnace of the present invention also includes a belt conveyor mechanism, which includes an active roller 21, a conveyor belt 22, and a driven roller 23. The active roller 21 is arranged between the outlet of the insulation section 4 and the rear conveyor roller 103, and the driven roller 23 is arranged between the entrance of the low-temperature section 2 and the front conveyor roller 101. The conveyor belt 22 is connected between the active roller 21 and the driven roller 23 by transmission. The upper half of the conveyor belt 22 covers the bottom wheel 11, and the width of the conveyor belt 22 is adapted to the width of the groove supporting the inner core 10. The conveyor belt 22 is woven with high-temperature resistant ceramic fiber cloth.

[0055] By setting a conveyor belt 22 throughout the length of the continuous induction furnace body, power transmission can be formed in the cavity of the continuous induction furnace body, thereby reducing the restriction on the length of the steel billet 13; by covering the conveyor belt 22 on the bottom wheel 11, the friction resistance during the transportation process can be reduced.

[0056] Specifically, if Figure 6 As shown, the belt conveyor mechanism further includes a tensioning wheel 24, a transfer wheel 25, a tensioning bracket, an auxiliary material supply box 27 and a tension spring 26. The tensioning bracket is arranged below one end of the conveyor belt 22 close to the driven roller 23. The tensioning bracket is connected to the lower part of the conveyor bracket 1 through a pin shaft in the middle, and the working end of the tensioning bracket is installed with a tensioning wheel 24 and a transfer wheel 25 that are split and rollingly meshed. The tensioning wheel 24 is pressed against the conveyor belt 22, and the transfer wheel 25 can dip the coating material from the auxiliary material supply box 27 below, and the coating material is a wet clay brick powder.

[0057] The coating material is dipped into the transfer wheel 25 and transferred to the tensioning wheel 24. The tensioning wheel 24 brushes the coating material onto the outer ring surface of the conveyor belt 22 while tensioning the conveyor belt 22. The coating material can effectively prevent the steel billet 13 from being damaged by heat bonding when in contact with the conveyor belt 22 for a long time, thereby ensuring the normal conveying operation of the conveyor belt 22.

[0058] Specifically, if Figure 6 As shown, the tension spring 26 is tightened at the other end of the tension bracket. Both ends of the tension spring 26 are fixed with screws. By adjusting the effective length of the screw, the tension of the tension spring 26 can be effectively adjusted, thereby adjusting the tension of the conveyor belt 22.

[0059] In a specific implementation of this embodiment, Figure 6 As shown, the belt conveyor mechanism also includes an auxiliary material recovery component arranged behind the active roller 21, and the auxiliary material recovery component includes a proximity switch 28, a felt brush 29, a cylinder 30 and an auxiliary material recovery box 31. The proximity switch 28 is a non-contact induction switch, which is arranged behind the active roller 21 and collects the signal of the steel billet 13 passing through and transmits it to the control system. The cylinder 30 is fixedly installed on the conveying bracket 1 with its head facing up, and the piston rod end of the cylinder 30 is connected to the felt brush 29. When the cylinder 30 is pushed out, the felt brush 29 can scrape the bottom surface of the steel billet 13 during the conveying process. The auxiliary material recovery box 31 is installed in front of the cylinder 30 and collects the coating material that falls on the bottom surface of the upper steel billet 13 and the conveyor belt 22 during the flipping process.

[0060] Specifically, the flange of the auxiliary material recovery box 31 facing the cylinder 30 provides a closed shielding protection for the cylinder 30 to prevent debris from falling onto the cylinder 30 and causing damage thereto.

[0061] The auxiliary material recovery component can be used to recover the coating material dropped during the turning of the conveyor belt 22. Meanwhile, the felt brush 29 and the cylinder 30 can be used to clean a small amount of coating material adhering to the lower surface of the billet 13 to prevent it from entering the rolling process.

[0062] For heating the steel billet 13 whose length is less than 1.5 times the length of the continuous induction furnace body, when the high-efficiency steel rolling heating furnace of this embodiment is working, the front conveying roller 101 conveys the short steel billet 13 into the inlet end of the continuous induction furnace body and enters above the driven roller 23 of the conveyor belt 22. The conveyor belt 22 carries the short steel billet 13 and conveys it along the tunnel cavity of the continuous induction furnace body at a set speed, and is inductively heated during the conveying process. During this process, the transfer wheel 25 and the tensioning wheel 24 brush the coating material on the outer ring surface of the conveyor belt 22, and the coating material can effectively isolate the steel billet 13 and prevent the steel billet 13 from being thermally bonded under long-term contact with the conveyor belt 22. At the outlet end of the continuous induction furnace, the coating material that falls during the turning of the conveyor belt 22 is collected by the auxiliary material recovery box 31 below. When the conveyor belt 22 carries the short steel billet 13 toward the rear conveying roller 103, the steel billet 13 collected by the proximity switch 28 is transmitted to the control system through a signal. The control system controls the cylinder 30 to push out, and the felt brush 29 scrapes the bottom surface of the steel billet 13 during the conveying process to prevent the coating material from being transferred backwards.

[0063] Example 4

[0064] The invention also discloses a working method of a steel rolling heating furnace, which uses a continuous induction furnace body to carry out segmented temperature increase on a steel billet that needs to be heated to meet the rolling requirements.

[0065] Specifically, nitrogen is introduced into the continuous induction furnace to provide anti-oxidation protection during the heating process, which can significantly reduce oxidation losses.

[0066] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A high-efficiency steel rolling heating furnace, characterized in that: The invention comprises a conveying support (1), a continuous induction furnace body and a temperature sensor (6), wherein the continuous induction furnace body comprises a low-temperature section (2), a high-temperature section (3) and a heat-insulating section (4) which are continuously connected from front to back at the middle position of the conveying support (1); the low-temperature section (2) comprises a shell, an induction body (8), a casting layer (9) and a supporting inner core (10); the shell is a rectangular shell made of non-magnetic conductive material, and square holes for material to pass through are arranged on both end surfaces of the rectangular shell; the casting layer (9) is cast and formed on the inner wall of the shell using refractory castable material, the induction body (8) is buried in the casting layer (9) and its two ends protrude from the shell to connect with an induction power supply and a cooling system; the supporting inner core (10) can be detachably mounted on the casting layer (9) 9) at the lower part of the middle square hole, the cross section of the support inner core (10) is U-shaped, a plurality of bottom wheels (11) are arranged at the bottom of the groove of the support inner core (10), and a plurality of side wheels (12) are arranged on the side wall of the groove of the support inner core (10), and the bottom wheels (11) and the side wheels (12) roll in contact with the bottom and side surfaces of the steel billet (13) to be heated; the structural form of the high temperature section (3) and the heat preservation section (4) are consistent with the low temperature section (2), except that the configuration parameters of the induction body (8) are different; the number of the temperature sensors (6) is three and they are respectively arranged at the discharge ends of the low temperature section (2), the high temperature section (3) and the heat preservation section (4), and the temperature sensor (6) collects the temperature signal of the surface of the steel billet (13) and feeds it back to the equipment control system.

2. The high-efficiency steel rolling heating furnace according to claim 1 is characterized in that: The low-temperature section (2) is provided with a docking flange edge (5) at one end facing the high-temperature section (3), the high-temperature section (3) is provided with docking flange edges (5) at both ends, and the heat-insulating section (4) is provided with a docking flange edge (5) at one end facing the high-temperature section (3), and the three are detachably connected together via the docking flange edges (5).

3. The high-efficiency steel rolling heating furnace according to claim 1 is characterized in that: The conveying support (1) is provided with a front conveying roller (101) on the front side of the low-temperature section (2), and the conveying support (1) is provided with a rear conveying roller (103) on the rear side of the heat-insulating section (4); the top edges of the front conveying roller (101) and the rear conveying roller (103) are flush with the top edge of the bottom wheel (11); and the front conveying roller (101) and the rear conveying roller (103) are both driven by a controllable servo motor.

4. The high-efficiency steel rolling heating furnace according to claim 1 is characterized in that: The invention also comprises a protective gas input mechanism, which comprises a gas source, a valve group and a gas pipe joint (7). The gas pipe joint (7) is arranged on the cylinder wall of the high-temperature section (3), and the inner end of the gas pipe joint (7) is connected to the inner cavity of the high-temperature section (3); the gas source supplies protective gas to the gas pipe joint (7) through the valve group.

5. The high-efficiency steel rolling heating furnace according to claim 4 is characterized in that: The air pipe joint (7) comprises a pipe joint body, an external thread section (701), an air nozzle (702) and a lock nut (703); the input end of the pipe joint body passes through a through hole on the top wall of the high temperature section (3) shell and is then threadedly connected to the external thread section (701) by the lock nut (703) for locking; the external thread section (701) protrudes out of the end to connect to the pipeline of the valve group; the two air nozzles (702) are arranged at the output end of the pipe joint body in a forked manner and in communication with each other; the two air nozzles (702) are arranged towards the low temperature section (2) and the heat preservation section (4) respectively.

6. The high-efficiency steel rolling heating furnace according to claim 3 is characterized in that: It also includes an auxiliary pushing mechanism arranged above the front conveying roller (101), the auxiliary pushing mechanism including an action cylinder (14), a cylinder support (15), a connecting plate (16), a guide rod (17) and a pushing assembly, the action cylinder (14) being arranged horizontally above the front conveying roller (101) and connected to the heightening support frame of the conveying bracket (1) through the cylinder support (15) at the end; the piston rod of the action cylinder (14) is directed toward the low-temperature section (2) and the end is connected to the connecting plate (16), the bottom end of the connecting plate (16) is connected to the guide rod (17) below, and the end of the guide rod (17) facing the feeding direction is connected to the pushing assembly, and the pushing assembly can assist in pushing the steel billet (13) through the continuous induction furnace body.

7. The high-efficiency steel rolling heating furnace according to claim 6 is characterized in that: The pushing assembly comprises a fixed block (18) and a movable pushing block (19); a vertical plate of the fixed block (18) is locked on the end of the guide rod (17) by a nut; an end of the bottom plate of the fixed block (18) facing the low-temperature section (2) is connected to the movable pushing block (19) by a pin shaft (20); and a cushion block (181) is provided at one end of the bottom plate of the fixed block (18) away from the pin shaft (20); when the top plate of the movable pushing block (19) contacts the cushion block (181), the vertical plate of the movable pushing block (19) is in a vertical position and can contact the rear end surface of the steel billet (13).

8. The high-efficiency steel rolling heating furnace according to claim 3 is characterized in that: The invention also comprises a belt conveying mechanism, wherein the belt conveying mechanism comprises a driving roller (21), a conveying belt (22), and a driven roller (23), wherein the driving roller (21) is arranged between the outlet of the heat preservation section (4) and the rear conveying roller (103), and the driven roller (23) is arranged between the inlet of the low-temperature section (2) and the front conveying roller (101), and the conveying belt (22) is transmission-connected between the driving roller (21) and the driven roller (23), and the upper half of the conveying belt (22) covers the bottom wheel (11).

9. The high-efficiency steel rolling heating furnace according to claim 8, characterized in that: The belt conveyor mechanism also includes a tensioning wheel (24), a transfer wheel (25), a tensioning bracket, an auxiliary material supply box (27) and a tension spring (26); the tensioning bracket is connected to the lower part of the conveying bracket (1) through a pin shaft in the middle; the working end of the tensioning bracket is installed with a tensioning wheel (24) and a transfer wheel (25) that are split and meshed; the tensioning wheel (24) is pressed against the conveying belt (22); the transfer wheel (25) can dip the coating material from the auxiliary material supply box (27); and the tension spring (26) is tightened at the other end of the tensioning bracket.

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