Low-energy-consumption electromagnetic heat compensation method for direct rolling of steel billets of 16 meters

Abstract

The invention relates to the technical field of bar wire steel billet direct rolling electromagnetic heat compensation, in particular to a 16-meter steel billet direct rolling low-energy-consumption electromagnetic heat compensation method, a bar wire is provided with four independently-controlled electromagnetic coils, and each electromagnetic coil is connected with an inverter; a single heating mode and an overall heating mode are designed for the billet temperature compensation system, and the billet head and the billet tail are independently heated according to the billet incoming material temperature; 10 heating temperature sections are designed for the steel billet temperature compensation system, different heating speeds are configured, and after setting is completed, given voltages of the 10 temperature sections are automatically selected according to different temperatures of supplied steel billets, so that the temperature of the steel billets passing through the electromagnetic heat compensation furnace is locked within a limited range; overall heating or single-support starting and stopping can be freely selected according to different types of produced steel; head heating, tail heating and a preferential stopping function are realized according to the head and tail temperature difference of the steel billet; electromagnetic heat compensation of direct rolling of the steel billet of 16 meters is achieved, the temperature difference is effectively controlled, and energy consumption is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of electromagnetic heating supplementation for direct rolling of bar wire steel billets, and in particular to a low-energy consumption electromagnetic heating supplementation method for direct rolling of 16-meter steel billets. Background Art

[0002] In steel production, the direct rolling technology of bar lines can effectively reduce energy consumption and improve efficiency. Electromagnetic heating technology is used to accurately control the temperature of the billet, ensure the rolling quality and reduce energy consumption. Electromagnetic heating heats the surface of the billet through electromagnetic induction to make it reach the required temperature for rolling. Compared with traditional heating methods, electromagnetic heating has the advantages of rapid heating, precise temperature control, energy saving and environmental protection. The billet direct rolling process includes billet preparation, electromagnetic heating, direct rolling, and cooling. The billet direct rolling combined with low-energy electromagnetic heating technology can effectively reduce energy consumption, improve production efficiency and product quality, and is an important development direction for the steel industry.

[0003] The direct rolling length of 16-meter steel billets is relatively long. At present, the direct rolling technology of 12-meter steel billets has been realized in China, but there is no electromagnetic heating technology for 16-meter steel billets. The temperature of the existing electromagnetic heating steel billets is uneven, and the temperature difference between the head and the tail is about 50 degrees. The power consumption is relatively high, reaching about 10 degrees. The uneven incoming temperature of a single steel billet leads to a large temperature difference of about 30 degrees for a single steel billet after heating. Therefore, a low-energy electromagnetic heating method for direct rolling of 16-meter steel billets is needed to solve the gap in the existing electromagnetic heating technology for direct rolling of 16-meter steel billets and the problem of high energy consumption caused by large temperature differences in electromagnetic heating of other sizes. Summary of the invention

[0004] In view of the problems existing in the prior art, the object of the present invention is to provide a low-energy consumption electromagnetic heating method for direct rolling of 16-meter steel billets.

[0005] The technical solution adopted by the present invention to solve the technical problem is: a low-energy consumption electromagnetic heating method for direct rolling of a 16-meter steel billet, comprising the following steps:

[0006] S1, the bar line is equipped with 4 independently controlled electromagnetic coils, each electromagnetic coil is connected to an inverter;

[0007] S2. The billet heating system is designed with single heating mode and overall heating mode, and the billet head and billet tail are heated separately according to the billet incoming material temperature;

[0008] S3. The billet heating system is designed with 10 heating temperature sections and equipped with different heating speeds. After setting, it automatically selects the given voltages of the 10 temperature sections according to the different incoming temperatures of the billets, so that the temperature after passing through the electromagnetic heating furnace is locked within the specified range.

[0009] Specifically, the continuous casting billet upstream of the bar line in step S1 is directly and quickly sent to the induction heating device by the roller table. The induction heating device automatically performs temperature compensation on the billet according to the incoming billet temperature. After the billet reaches the required temperature, it is transported to the downstream rolling mill for rolling. For the 16-meter-long hot-delivered billet, the surface temperature of the billet head is limited to ≥830°C. When the surface temperature of the billet head is 830°C, the surface temperature of the billet tail is not lower than 890°C.

[0010] Specifically, the heating power of the electromagnetic coil in step S1 is 1800KW, and the four electromagnetic coils are controlled by two groups of rectifier transformers. The heating power of each electromagnetic coil and the target temperature of the blank are closed-loop controlled. If one group of electromagnetic coils fails, it is removed and the remaining three groups are used. The heating speed of the electromagnetic coil is ≥320t / h, the supplementary heating temperature is 100°C, and the heating time is ≤36s; the running speed of the electromagnetic supplementary heating roller is ≥0.44m / s, and the maximum speed of the induction heating roller is ≥1.5m / s.

[0011] Specifically, the billet temperature compensation system in step S2 is provided with a power control module, a frequency converter control module, and a production line operation module. The power control module includes a rectifier cabinet, inverter 1, inverter 2, inverter 3, and inverter 4. The frequency converter control module includes 1# inverter, 2# inverter, 3# inverter, and 4# inverter. The production line operation module includes a parameter setting part and a button control part.

[0012] Specifically, the overall heating mode in step S2 is that when the segmented temperature is not selected before it is put into operation, the electromagnetic coil will output voltage according to the four set values ​​of inverter 1, inverter 2, inverter 3 and inverter 4 set set by the billet temperature compensation system, and the roller will operate according to the roller heating speed set value during heating;

[0013] When the single heating mode is selected before the segmented temperature is put into operation and the head heating is selected, when the temperature acquisition value does not meet the temperature range set by the head parameter, the electromagnetic coil will output voltage according to the four set values ​​of inverter 1 given, inverter 2 given, inverter 3 given, and inverter 4 given set above. When heating, the roller will run according to the roller heating speed setting value.

[0014] Specifically, the setting parameter part sets the head heating time, the speed reduction time in front of the furnace, the speed reduction time after the furnace, the temperature collection time and the speed priority shutdown time. The head heating time is when the head heating mode is selected. After the 4# heat inspection has a signal after the billet is out of the furnace, the transmission speed is increased by the delay setting value, and the speed is increased to the roller speed setting value; the speed reduction time in front of the furnace is after the 1# heat inspection has a signal after the billet is out of the straightening machine. The transmission speed is reduced by the delay setting value, and the speed is reduced to the roller heating speed setting value; the speed reduction time after the furnace: after the 4# heat inspection has a signal after the billet is out of the furnace, the transmission speed is reduced by the delay setting value, and the speed is reduced to the roller heating speed setting value; the speed reduction time after the furnace: after the 4# heat inspection has a signal after the billet is out of the furnace, the transmission speed is reduced by the delay setting value, and the speed is reduced to the roller heating speed setting value. The roller table behind the furnace slows down to the set value of the roller heating speed; temperature collection time: the timing starts after the 1# heat detector of the steel billet leaves the straightening machine has a signal, and the average of the maximum values ​​of the 1# pyrometer and the 2# pyrometer is taken as the collection value within the set time; speed-up priority shutdown time: when there is a signal from the 4# heat detector after the steel billet leaves the furnace, and the head heating time is delayed to the set value, the roller table starts to speed up, and the speed-up priority shutdown time setting value is delayed after the speed-up. The selected inverter will be shut down first, and the others that are not selected will be shut down after the steel billet completely leaves the furnace body.

[0015] Specifically, the billet heating system in step S3 is designed with 10 heating temperature sections and equipped with different heating speeds. According to the production design, the incoming material temperature will not be lower than 830°C and higher than 970°C. 830°C to 970°C is divided into 10 temperature sections, and each section is 14°C. The corresponding heating speed is 0.41m / s-0.5m / s. The heating speed changes by 0.01m / s for each temperature section. The heating time changes automatically according to the incoming material temperature.

[0016] Specifically, when the incoming material temperature is between 820°C and 834°C, the heating voltages given to the four electromagnetic coils are all 1300V, and the heating speed is 0.41m / s. When the incoming material temperature is between 956°C and 970°C, the heating voltages given to the four electromagnetic coils will be automatically adjusted to 1200V, 1150V, 1100V, and 950V, and the heating speed will automatically become 0.5m / s.

[0017] The present invention has the following beneficial effects:

[0018] The low-energy electromagnetic heating method for direct rolling of 16-meter steel billets designed by the present invention can freely select overall heating or single-branch start and stop according to different types of steel produced; realize head heating and tail heating as well as priority stop functions according to the temperature difference between the head and tail of the steel billet; design 10 different heating temperature sections according to different incoming material temperatures and give different voltages according to different temperatures; realize electromagnetic heating for direct rolling of 16-meter steel billets, effectively control temperature differences, and reduce energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is the interface diagram of the billet heating system.

[0020] Figure 2 This is the interface diagram of the parameter setting part of the production line operation module.

[0021] Figure 3 This is the interface diagram of the button control part of the production line operation module.

[0022] Figure 4 This is the interface diagram of the overall parameter settings of the parameter setting part of the production line operation module.

[0023] Figure 5 This is the interface diagram of the header parameter settings in the parameter setting part of the production line operation module. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely further describe the technical solutions in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0025] like Figure 1 As shown, a low-energy electromagnetic heating method for direct rolling of a 16-meter steel billet comprises the following steps:

[0026] 1. The bar line is equipped with 4 independently controlled electromagnetic coils, each of which is connected to an inverter. The continuous casting billet upstream of the bar line is directly and quickly sent to the induction heating device by the roller table. The induction heating device automatically compensates the temperature of the billet according to the incoming billet temperature. After the billet reaches the required temperature, it is transported to the downstream rolling mill for rolling. For the 16-meter-long hot-delivered billet, the surface temperature of the billet head is limited to ≥830℃. When the surface temperature of the billet head is 830℃, the surface temperature of the billet tail is not less than 890℃.

[0027] The heating power of the electromagnetic coil is 1800KW. The four electromagnetic coils are controlled by two groups of rectifier transformers. The heating power of each electromagnetic coil and the target temperature of the billet are controlled in a closed loop. If one group of electromagnetic coils fails, the remaining three groups will be used separately. The heating speed of the electromagnetic coil is ≥320t / h, the supplementary heating temperature is 100℃, and the heating time is ≤36s; the running speed of the electromagnetic supplementary heating roller is ≥0.44m / s, and the maximum speed of the induction heating roller is ≥1.5m / s; the power consumption per ton of steel is ≤10kW·h / t; the power factor of the power supply within the full power range is ≥0.92 (the measurement point is the power input terminal); the roller diameter of the middle roller of the coil is 300mm; the surface temperature difference between the head and tail (length direction) of the heated mass billet is ≤30℃.

[0028] 2. The billet heating system is designed with single heating mode and overall heating mode, and heats the billet head and billet tail separately according to the incoming billet temperature; it saves power consumption and balances the temperature difference between the billet head and tail and the fluctuation of the billet's smoothness. The billet heating system is equipped with power control module, inverter control module, and production line operation module. The power control module includes rectifier cabinet, inverter 1, inverter 2, inverter 3, inverter 4, inverter control module includes 1# inverter, 2# inverter, 3# inverter, 4# inverter, and production line operation module includes parameter setting part and button control part.

[0029] 2.1 Rectifier cabinet:

[0030] Internal control mode: local operation instructions of the power cabinet;

[0031] External control mode: remote operation instructions of the power cabinet;

[0032] Ready: Power cabinet closing indication;

[0033] Fault 1: Power cabinet rectifier fault 1 indication;

[0034] Fault 2: Power cabinet rectifier fault 2 indication;

[0035] Flow 1: Status indicator of the return flow switch 1 of the power cabinet, green for normal operation and red for abnormal operation;

[0036] Flow 2: Status indicator of the return flow switch 2 of the power cabinet, green for normal operation and red for abnormal operation;

[0037] DC voltage 1: Display value of DC voltage 1 of power supply cabinet;

[0038] DC voltage 2: Display value of DC voltage 2 of power supply cabinet;

[0039] Water inlet flow: water flow display value of power cabinet;

[0040] Water inlet pressure: Display value of water inlet pressure of power cabinet;

[0041] Inlet water temperature: Display value of the inlet water temperature of the power cabinet.

[0042] 2.2 Inversion 1:

[0043] Fault: Power cabinet inverter 1 fault indication;

[0044] Flow 1: Status indicator of the return flow switch 1 of the power cabinet, green for normal operation and red for abnormal operation;

[0045] Flow 2: Status indicator of the return flow switch 2 of the power cabinet, green for normal operation and red for abnormal operation;

[0046] Capacitor pressure: Power cabinet capacitor pressure indicator, red is abnormal, gray is normal;

[0047] Water inlet flow: water flow display value of power cabinet;

[0048] Water inlet pressure: Display value of water inlet pressure of power cabinet;

[0049] Inlet water temperature: Display value of the inlet water temperature of the power cabinet.

[0050] 2.3 Inversion 2:

[0051] Fault: Power cabinet inverter 1 fault indication;

[0052] Flow 1: Status indicator of the return flow switch 1 of the power cabinet, green for normal operation and red for abnormal operation;

[0053] Flow 2: Status indication of the return flow switch 2 of the power cabinet, green for normal and red for abnormal; Capacitor pressure: Capacitor pressure indication of the power cabinet, red for abnormal and gray for normal;

[0054] Water inlet flow: water flow display value of power cabinet;

[0055] Water inlet pressure: Display value of water inlet pressure of power cabinet;

[0056] Inlet water temperature: Display value of the inlet water temperature of the power cabinet.

[0057] 2.4 Inversion 3:

[0058] Fault: Power cabinet inverter 1 fault indication;

[0059] Flow 1: Status indication of the return flow switch 1 of the power cabinet, green for normal and red for abnormal; Flow 2: Status indication of the return flow switch 2 of the power cabinet, green for normal and red for abnormal; Capacitor pressure: Capacitor pressure indication of the power cabinet, red for abnormal and gray for normal;

[0060] Water inlet flow: water flow display value of power cabinet;

[0061] Water inlet pressure: Display value of water inlet pressure of power cabinet;

[0062] Inlet water temperature: Display value of the inlet water temperature of the power cabinet.

[0063] 2.5 Inversion 4:

[0064] Fault: Power cabinet inverter 1 fault indication;

[0065] Flow 1: Status indication of the return flow switch 1 of the power cabinet, green for normal and red for abnormal; Flow 2: Status indication of the return flow switch 2 of the power cabinet, green for normal and red for abnormal; Capacitor pressure: Capacitor pressure indication of the power cabinet, red for abnormal and gray for normal;

[0066] Water inlet flow: water flow display value of power cabinet;

[0067] Water inlet pressure: Display value of water inlet pressure of power cabinet;

[0068] Inlet water temperature: Display value of the inlet water temperature of the power cabinet.

[0069] 2.6 1# inverter:

[0070] Speed: Real-time speed of 1# inverter motor;

[0071] Running: The running status of the 1# inverter motor;

[0072] Fault: Fault status of 1# inverter motor;

[0073] Reset: Click this button to reset the fault of 1# inverter.

[0074] 2.7 2# inverter:

[0075] Speed: Real-time speed of 2# inverter motor;

[0076] Running: The running status of the 2# inverter motor;

[0077] Fault: Fault status of 2# inverter motor;

[0078] Reset: Click this button to reset the fault of 2# inverter.

[0079] 2.8 3# inverter:

[0080] Speed: Real-time speed of 3# inverter motor;

[0081] Running: The running status of the 3# inverter motor;

[0082] Fault: Fault status of 3# inverter motor;

[0083] Reset: Click this button to reset the fault of 3# inverter.

[0084] 2.9 4# inverter:

[0085] Speed: Real-time speed of 4# inverter motor;

[0086] Running: The running status of the 4# inverter motor;

[0087] Fault: Fault status of 4# inverter motor;

[0088] Reset: Click this button to reset the fault of 4# inverter.

[0089] 2.10 Production line operation module such as Figure 2 shown.

[0090] Inverter 1 setting: Inverter 1 output voltage setting value;

[0091] Inverter 2 setting: Inverter 2 output voltage setting value;

[0092] Inverter 3 setting: Inverter 3 output voltage setting value;

[0093] Inverter 4 setting: Inverter 4 output voltage setting value;

[0094] Roller speed: The speed setting value of the roller when the heating furnace is disabled;

[0095] Roller heating speed: The speed setting value of the roller during heating.

[0096] The overall heating mode is when the segmented temperature is not selected before it is put into operation. The electromagnetic coil will output voltage according to the four set values ​​of inverter 1, inverter 2, inverter 3 and inverter 4 set set by the billet temperature compensation system. During heating, the roller will run according to the roller heating speed set value.

[0097] When the single heating mode is selected before the segmented temperature is put into operation and the head heating is selected, when the temperature acquisition value does not meet the temperature range set by the head parameter, the electromagnetic coil will output voltage according to the four set values ​​of inverter 1 given, inverter 2 given, inverter 3 given, and inverter 4 given set above. When heating, the roller will run according to the roller heating speed setting value.

[0098] In the parameter setting part, the head heating time, the speed reduction time before the furnace, the speed reduction time after the furnace, the temperature collection time and the speed priority shutdown time are set. The head heating time is when the head heating mode is selected. After the 4# heat inspection has a signal after the billet comes out of the furnace, the transmission speed is increased by the delay setting value to the roller speed setting value; the speed reduction time before the furnace is the delay setting value after the 1# heat inspection has a signal after the billet comes out of the straightening machine. The transmission speed is reduced to the roller heating speed setting value; the speed reduction time after the furnace: after the 4# heat inspection has a signal after the billet comes out of the furnace, the delay setting value The roller behind the furnace slows down to the set value of the roller heating speed; temperature collection time: the timing starts after there is a signal from the 1# heat detector of the steel billet leaving the straightening machine, and the average of the maximum values ​​of the 1# pyrometer and the 2# pyrometer is taken as the collection value within the set time; speed-up priority shutdown time: when there is a signal from the 4# heat detector after the steel billet leaves the furnace, and the head heating time is delayed to the set value, the roller starts to speed up, and after speeding up, the speed-up priority shutdown time setting value is delayed. The selected inverter will be shut down first, and the others that are not selected will be shut down after the steel billet completely leaves the furnace body.

[0099] The overall parameter settings are as follows Figure 4 As shown, the header parameters are set as Figure 5 shown.

[0100] The button control part of the production line operation module is as follows Figure 3 shown.

[0101] Checking the temperature segmentation and selecting the head heating indicates that the electromagnetic heating will work in the head heating mode, and the inverter 1, inverter 2, inverter 3, inverter 4 and roller heating speed will work according to the voltage setting and speed setting in the head parameters corresponding to the temperature acquisition value.

[0102] Unchecked: Single start and stop: Inverter 1, Inverter 2, Inverter 3, Inverter 4 will start and stop according to the signals of 1# thermal detection and 4# thermal detection.

[0103] Start: Under the premise that the rectifier, inverter 1, inverter 2, inverter 3, and inverter 4 are all closed, when there is a signal from the 1# thermal detection, inverter 1 will start automatically, inverter 2 will start after a delay of 2s, inverter 3 will start after a delay of 4s, and inverter 4 will start after a delay of 6s.

[0104] Stop: 1) If the option of shutting down the inverter before speed increase is not checked, inverter 1, inverter 2, inverter 3, and inverter 4 will be shut down after the 4# thermal detection signal changes from being present to being absent. 2) If the option of shutting down the inverter before speed increase is checked, the selected inverter cabinet will be shut down first after the roller speed increase delay setting value, and then the unselected inverter cabinet will be shut down after the 4# thermal detection signal changes from being present to being absent.

[0105] Continuous operation: After the rectifier and inverter are closed, the inverter cabinet will start working directly. To stop working, you need to turn off the inverter first and then the rectifier.

[0106] Check the option to disable electromagnetic heating: After selecting, the roller will run according to the roller speed setting value and will not be affected by other factors.

[0107] 3. In order to further reduce power consumption and solve the problem of large temperature difference between branches, the billet heating system is designed with 10 heating temperature sections and equipped with different heating speeds. After setting, it automatically selects the given voltage of 10 temperature sections according to the different incoming temperatures of the billet, so that the temperature after passing through the electromagnetic heating furnace is locked within the limited range, reducing the temperature difference between branches and reducing power consumption.

[0108] Because the steelmaking pulling speed is different, and the time from steelmaking to steel rolling is also different, the incoming material temperature will inevitably be different. If the same power is used to heat the billets of different temperatures, the temperature difference between the billets after heating will be too large. The temperature of the incoming material with high temperature will be too high after heating, and the temperature of the incoming material with low temperature may not meet the rolling requirements after heating. In addition, the temperature variation between branches is large, and the rolling line cannot be adjusted. Therefore, the billet heating system is designed with 10 heating temperature sections and equipped with different heating speeds. According to the production design, the minimum incoming material temperature will not be lower than 830℃ and the maximum will not be higher than 970℃. 830℃ to 970℃ is divided into 10 temperature sections, and each 14℃ is a temperature section. The corresponding heating speed is 0.41m / s-0.5m / s. The heating speed changes every 0.01m / s corresponding to a temperature section. The heating time automatically changes according to the different incoming material temperatures.

[0109] Specifically, when the incoming material temperature is between 820℃ and 834℃, the heating voltages given to the four electromagnetic coils are all 1300V, and the heating speed is 0.41m / s. When the incoming material temperature is between 956℃ and 970℃, the heating voltages given to the four electromagnetic coils will be automatically adjusted to 1200V, 1150V, 1100V, and 950V, and the heating speed will automatically become 0.5m / s.

[0110] The present invention is not limited to the above-mentioned implementation modes, and anyone should be aware of the structural changes made under the enlightenment of the present invention, and all those having the same or similar technical solutions as the present invention fall within the protection scope of the present invention.

[0111] The techniques, shapes, and structural parts not described in detail in the present invention are all well-known techniques.

Claims

1. A low-energy electromagnetic heating method for direct rolling of 16-meter steel billets, characterized in that: The following steps are involved: S1, the bar line is equipped with 4 independently controlled electromagnetic coils, each electromagnetic coil is connected to an inverter; S2. The billet heating system is designed with single heating mode and overall heating mode, and the billet head and billet tail are heated separately according to the billet incoming material temperature; S3. The billet heating system is designed with 10 heating temperature sections and equipped with different heating speeds. After setting, it automatically selects the given voltages of the 10 temperature sections according to the different incoming temperatures of the billets, so that the temperature after passing through the electromagnetic heating furnace is locked within the specified range.

2. The low-energy electromagnetic heating method for direct rolling of 16-meter steel billets according to claim 1 is characterized in that: The continuous casting billet upstream of the bar line in step S1 is directly and quickly sent to the induction heating device by the roller table. The induction heating device automatically performs temperature compensation on the billet according to the incoming billet temperature. After the billet reaches the required temperature, it is transported to the downstream rolling mill for rolling. For the 16-meter-long hot-sent billet, the surface temperature of the billet head is limited to ≥830°C. When the surface temperature of the billet head is 830°C, the surface temperature of the billet tail is not less than 890°C.

3. The low-energy electromagnetic heating method for direct rolling of 16-meter steel billets according to claim 1 is characterized in that: The heating power of the electromagnetic coil in step S1 is 1800KW, and the four electromagnetic coils are controlled by two groups of rectifier transformers. The heating power of each electromagnetic coil and the target temperature of the blank are closed-loop controlled. If one group of electromagnetic coils fails, it is removed and the remaining three groups are used. The heating speed of the electromagnetic coil is ≥320t / h, the supplementary heating temperature is 100℃, and the heating time is ≤36s; the running speed of the electromagnetic supplementary heating roller is ≥0.44m / s, and the maximum speed of the induction heating roller is ≥1.5m / s.

4. The low-energy electromagnetic heating method for direct rolling of 16-meter steel billets according to claim 1 is characterized in that: The billet temperature compensation system in step S2 is provided with a power control module, a frequency converter control module, and a production line operation module. The power control module includes a rectifier cabinet, inverter 1, inverter 2, inverter 3, and inverter 4. The frequency converter control module includes 1# inverter, 2# inverter, 3# inverter, and 4# inverter. The production line operation module includes a parameter setting part and a button control part.

5. The low-energy electromagnetic heating method for direct rolling of 16-meter steel billets according to claim 4 is characterized in that: The overall heating mode in step S2 is that when the segmented temperature is not selected before the input, the electromagnetic coil will output voltage according to the four set values ​​of inverter 1, inverter 2, inverter 3 and inverter 4 set set by the billet temperature compensation system, and the roller will operate according to the roller heating speed set value during heating; When the single heating mode is selected before the segmented temperature is put into operation and the head heating is selected, when the temperature acquisition value does not meet the temperature range set by the head parameter, the electromagnetic coil will output voltage according to the four set values ​​of inverter 1 given, inverter 2 given, inverter 3 given, and inverter 4 given set above. When heating, the roller will run according to the roller heating speed setting value.

6. The low-energy electromagnetic heating method for direct rolling of 16-meter steel billets according to claim 5 is characterized in that: The parameter setting part sets the head heating time, the speed reduction time before the furnace, the speed reduction time after the furnace, the temperature collection time and the speed priority shutdown time. The head heating time is when the head heating mode is selected. After the 4# heat detection signal is received after the billet is out of the furnace, the transmission speed is increased by the delay setting value to the roller speed setting value; the speed reduction time before the furnace is after the 1# heat detection signal is received after the billet is out of the straightening machine, and the transmission speed is reduced by the delay setting value to the roller heating speed setting value; the speed reduction time after the furnace: after the 4# heat detection signal is received after the billet is out of the furnace, the delay setting value is received. The roller speed after the furnace is slowed down to the set value of the roller heating speed; temperature collection time: the timing starts after the 1# heat detection signal is received when the billet leaves the straightening machine, and the average of the maximum values ​​of the 1# pyrometer and the 2# pyrometer is taken as the collection value within the set time; speed-up priority shutdown time: when there is a signal from the 4# heat detection after the billet leaves the furnace, and the head heating time is delayed to the set value, the roller starts to speed up, and after speeding up, the speed-up priority shutdown time setting value is delayed. The selected inverter will be shut down first, and the others that are not selected will be shut down after the billet completely leaves the furnace.

7. The low-energy electromagnetic heating method for direct rolling of 16-meter steel billets according to claim 1 is characterized in that: The billet heating system in step S3 is designed with 10 heating temperature sections and equipped with different heating speeds. According to the production design, the incoming material temperature will not be lower than 830°C and will not be higher than 970°C. 830°C to 970°C are divided into 10 temperature sections, and each section is 14°C. The corresponding heating speed is 0.41m / s-0.5m / s. The heating speed changes by 0.01m / s for each temperature section. The heating time changes automatically according to the different incoming material temperatures.

8. The low-energy electromagnetic heating method for direct rolling of 16-meter steel billets according to claim 7 is characterized in that: When the incoming material temperature is between 820℃ and 834℃, the heating voltages given to the four electromagnetic coils are all 1300V, and the heating speed is 0.41m / s. When the incoming material temperature is between 956℃ and 970℃, the heating voltages given to the four electromagnetic coils will be automatically adjusted to 1200V, 1150V, 1100V, and 950V, and the heating speed will automatically become 0.5m / s.

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