Control method for improving rolling rhythm of double-high-rod direct rolling process

Abstract

The invention relates to the field of ferrous metallurgy, in particular to a control method for improving the rolling rhythm of a double-high-rod direct rolling process, which provides a stable and continuous steel sending rhythm by setting a plurality of time thresholds as control parameters of the double-high-rod direct rolling process, and improves the rolling rhythm of the double-high-rod direct rolling process by dynamically adjusting the steel passing interval time of a 6 # flying shear and a 10 # flying shear in real time. And abnormal conditions (steel billet slipping, steel stacking and cage drilling at the tail part of the rotating hub) are judged and processed in real time, so that accidents such as steel slipping, steel stacking and cage drilling at the tail part of the rotating hub can be prevented, the stability and continuity of a steel billet rolling production line are facilitated, the rolling rhythm of a double-high-rod direct rolling process can be improved, the production efficiency and the production quality can be improved, and the enterprise competitiveness can be improved.

Description

Technical Field

[0001] The present invention relates to the field of iron and steel metallurgy, and in particular to a control method for improving the rolling rhythm of a double-high bar direct rolling process. Background Art

[0002] In the modern steel industry, the double-high bar hot delivery until rolling process (referred to as the double-high bar direct rolling process) refers to the process of directly transporting the steel billet in a high temperature state from the continuous casting machine to the double-high bar rolling mill for rolling. The process mainly includes the rolling mill steel request, continuous casting steel, roller hot delivery, rolling mill rolling, etc. The double-high bar operator will first send a steel request signal according to the actual rolling situation of the steel billet. After receiving the steel request signal, the continuous casting machine will produce the steel billet. The produced steel billet will then be quickly hot-delivered to the rolling mill via the conveyor roller, and the rolling mill will roll it.

[0003] The whole process of the double-high bar direct rolling process is equipped with a heat detection device to detect the temperature of the steel billet in real time, and the rolling rhythm is controlled by the real-time temperature of the steel billet. However, as the market demand for double-high bars continues to grow, the target output of double-high bars continues to increase, and this control method gradually exposes many problems:

[0004] ① The steel demand rhythm of the rolling mill is unstable and discontinuous: The billet rolling production line of the double-high bar direct rolling process contains multiple complex links. Relying solely on the double-high bar operator to send the steel demand signal, it is not only impossible to accurately arrange the rolling process according to the rolling mill status and the actual temperature of the billet, but also often delays the sending of the steel demand signal due to the busyness of the double-high bar operator or other emergencies, resulting in the unstable and discontinuous steel demand rhythm of the rolling mill;

[0005] ② The gap time between the 6# and 10# shears is too long: The 6# and 10# flying shears use the heat detection signals generated by the heat detection device to identify different billets. In order to avoid similar heat detection signals generated by the front and rear billets, which may cause the 6# and 10# flying shears to fail to identify the billets and cause accidents such as steel piling and cage drilling at the tail of the hub, the 6# and 10# flying shears are respectively set with fixed protection distances and larger gap time between steel passing, which reduces the rolling rhythm of the double-high bar direct rolling process;

[0006] ③ No abnormal condition warning device: The hot delivery of double-high bars until the rolling process usually involves multiple production lines, and each production line covers multiple links. When the billet has an abnormal condition in a certain link (such as steel slippage, steel piling, steel drilling cage at the tail of the hub, etc.), the double-high bar operator often cannot directly observe it. Only when the abnormal condition further expands and seriously affects the rolling process, the double-high bar operator can know and take remedial measures. This not only easily damages the rolling mill equipment, but also increases production costs;

[0007] It can be seen that the above-mentioned problems will not only lead to a slow rolling rhythm and low output of the double-high bar direct rolling process, which is unable to cope with the rapidly growing market demand, but more seriously may even cause huge production accidents.

[0008] How to improve the rolling rhythm and increase the output of double-high bars as much as possible while ensuring production safety has always been an urgent problem to be solved by technicians in this technical field. Summary of the invention

[0009] The purpose of the present invention is to address the corresponding deficiencies in the prior art and to provide a control method for improving the rolling rhythm of the double-high bar direct rolling process. By setting multiple time thresholds and using them as control parameters of the double-high bar direct rolling process, a stable and continuous steel-making rhythm is provided. The steel-passing gap time of the 6# flying shear and the 10# flying shear is adjusted dynamically in real time, and abnormal conditions (steel billet slipping, steel piling, steel drilling in the cage at the tail of the hub) are judged and processed in real time, thereby improving the rolling rhythm of the double-high bar direct rolling process.

[0010] The object of the present invention is to achieve the following scheme: a control method for improving the rolling rhythm of a double-high bar direct rolling process, comprising the following steps:

[0011] 1) Set the steel-requiring time threshold, steel-biting time threshold, and target gap time threshold;

[0012] 2) setting a number of signal protection coefficients according to the target gap time threshold, and setting the steel gap time threshold of each flying shear according to the signal protection coefficient;

[0013] 3) Using the multiple time thresholds set in step 1) and step 2) as control parameters, the steel billet is rolled in a double-high rod direct rolling process.

[0014] Preferably, in step 2), a plurality of signal protection coefficients are set according to the target gap time threshold, and the specific manner of setting the steel gap time threshold of each flying shear according to the signal protection coefficient includes:

[0015] 2-1) Set the signal protection coefficient K1 of the 6A flying shear, and use the following formula to set the steel clearance time threshold T4 of the 6A flying shear:

[0016] K1=(T3-0.5)*V1 / L1

[0017] T4=K1*L1 / V1

[0018] Where, K1 is the signal protection coefficient of 6A flying shear, T3 is the target gap time threshold, T4 is the steel gap time threshold of 6A flying shear, L1 is the distance from 3A pinch roller to 6A flying shear, and V1 is the real-time speed of 6A pinch roller;

[0019] 2-2) Set the signal protection factor K2 of the 6B flying shear and use the following formula to adjust the gap time of the 6B flying shear:

[0020] K2=(T3-0.5)*V2 / L2

[0021] T5=K2*L2 / V2

[0022] Where, K2 is the signal protection coefficient of 6B flying shear, T3 is the target gap time threshold, T5 is the steel gap time threshold of 6B flying shear, L2 is the distance from 3B pinch roller to 6B flying shear, and V2 is the real-time speed of 6B pinch roller;

[0023] 2-3) Set the signal protection factor K3 of the 10A flying shear and use the following formula to adjust the gap time of the 10A flying shear passing through the steel:

[0024] K3=(T3-0.5)*V3 / L3

[0025] T6=K3*L3 / V3

[0026] Where, K3 is the signal protection coefficient of 10A flying shear, T3 is the target gap time threshold, T6 is the steel gap time threshold of 10A flying shear, L3 is the distance from finishing 2A to 10A flying shear, and V3 is the real-time speed of 10A pinch roller;

[0027] 2-4) Set the signal protection factor K4 of the 10A flying shear and use the following formula to calculate the steel clearance time of the 10B flying shear:

[0028] K4=(T3-0.5)*V4 / L4

[0029] T7=K4*L4 / V4

[0030] Wherein, K4 is the signal protection coefficient of 10B flying shear, T3 is the target gap time threshold, T7 is the steel gap time threshold of 10B flying shear, L4 is the distance from finishing 2B to 10B flying shear, and V4 is the real-time speed of 10B pinch roller.

[0031] Preferably, in step 3), the multiple time thresholds set in step 1) and step 2) are used as control parameters, and the specific method of rolling the steel billet in the double high bar direct rolling process includes:

[0032] 3-1) Use the steel demand time threshold to control the steel delivery rhythm;

[0033] 3-2) Using the steel biting time threshold to determine whether the billet is slipping;

[0034] 3-3) Using the target gap time threshold to determine whether there is a risk of too short gap time during steelmaking;

[0035] 3-4) Use several steel-passing gap time thresholds to dynamically adjust the protection distance of each flying shear, and determine whether the steel-passing gap time of each flying shear is too short.

[0036] Preferably, in step 3-1), the specific method of controlling the steel production rhythm by using the steel demand time threshold includes:

[0037] 3-1-1) The continuous casting machine receives the steel request signal from the rolling mill and performs steelmaking. After steelmaking is completed, it sends a steel delivery signal to the hot-feeding straight rolling roller table;

[0038] 3-1-2) The hot delivery straight rolling roller receives the steel sending signal, sends a signal prohibiting steel request to the rolling mill, and transports the steel billet from the continuous casting machine to the rolling mill within the steel request time threshold;

[0039] 3-1-3) When the tail of the billet leaves the hot delivery straightening roller for heat inspection, the hot delivery straight rolling roller table sends a signal to the rolling mill to release the prohibition of steel demand;

[0040] 3-1-4) The rolling mill receives the signal for lifting the prohibition on steel demand and waits. When the waiting time is equal to the steel demand time threshold, a steel demand signal is issued.

[0041] Preferably, in step 3-2), the specific method of using the steel biting time threshold to judge whether the steel billet is slipping includes:

[0042] 3-2-1) Calculate the time when the entrance of the 1# rack recognizes the head of the steel billet but does not bite the steel;

[0043] 3-2-2) comparing the time calculated in step 3-3-1) with the steel biting time threshold to determine whether the steel billet is slipping;

[0044] ① If the time when the billet head is identified but not bitten is less than the steel biting time threshold, the billet does not slip at the entrance of the 1# rack;

[0045] ② If the time of identifying the head of the billet but not biting the steel is greater than the steel biting time threshold, the steel slips at the entrance of the 1# frame, an alarm signal is issued, and the hot-feed straight rolling roller sends a signal prohibiting steel from being required to the rolling mill. The 1# and 2# rollers stop coming out of the furnace, and the 3# roller reverses to reverse and remove the slipping steel.

[0046] Preferably, in step 3-3), the specific method of using the target gap time threshold to determine whether there is a risk of too short gap time for steel passing includes:

[0047] 3-3-1) Calculate the actual steel gap time of the steel billet passing through the 1# rack and the 6# rack respectively;

[0048] 3-3-2) Compare the actual steel gap time of the steel billet passing through the 1# rack with the target gap time threshold to determine whether the steel gap time of the 1# rack is too short:

[0049] ① If the actual steel-passing gap time of the 1# rack is less than the target gap time threshold - 0.5, there is a risk that the steel billet may have a too short steel-passing gap time, and an alarm signal is issued;

[0050] ② If the actual steel-passing gap time of the 1# rack is ≥ the target gap time threshold - 0.5, there is no risk of the steel billet having a too short steel-passing gap time;

[0051] 3-3-3) Compare the actual gap time of the steel billet passing through the 6# rack with the target gap time threshold to determine whether the steel billet needs to be broken:

[0052] ① If the actual steel-passing gap time of the 6# frame is less than the target gap time threshold, the 1# flying shear is controlled to start automatic breaking;

[0053] ② If the actual steel gap time of the 6# rack is ≥ the target gap time threshold, the steel billet will not be automatically broken.

[0054] Preferably, in step 3-4), the specific method of dynamically adjusting the protection distance of each flying shear by using a plurality of steel-passing gap time thresholds and judging whether the steel-passing gap time of each flying shear is too short includes:

[0055] 3-4-1) Dynamically adjust the protection distance of each flying shear using several steel-passing gap time thresholds;

[0056] 3-4-2) Calculate the actual steel gap time of the steel billet passing through 6A flying shear, 6B flying shear, 10A flying shear and 10B flying shear respectively;

[0057] 3-4-3) Compare the actual steel gap time of the steel billet passing through the 6A flying shear with the 6A flying shear steel gap time threshold to determine whether the 6A flying shear steel gap time is too short:

[0058] ① If the actual gap time of the 6A flying shear passing through the steel is less than the gap time threshold of the 6A flying shear passing through the steel, the gap time of the 6A flying shear passing through the steel is too short, and the 6A flying shear is controlled to start automatically breaking;

[0059] ② If the actual gap time of 6A flying shear passing through steel is ≥ the gap time threshold of 6A flying shear passing through steel, the gap time of 6A flying shear passing through steel is not too short;

[0060] 3-4-4) Compare the actual steel gap time of the steel billet passing through the 6B flying shear with the 6B flying shear steel gap time threshold to determine whether the 6B flying shear steel gap time is too short:

[0061] ① If the actual gap time of 6B flying shear passing steel is less than the gap time threshold of 6B flying shear passing steel, the gap time of 6B flying shear passing steel is too short, and the 6B flying shear is controlled to start automatically breaking;

[0062] ② If the actual gap time of 6B flying shear passing steel is greater than or equal to the gap time threshold of 6B flying shear passing steel, the gap time of 6A flying shear passing steel is not too short;

[0063] 3-4-5) Compare the actual steel gap time of the steel billet passing through the 10A flying shear with the 10A flying shear steel gap time threshold to determine whether the 10A flying shear steel gap time is too short:

[0064] ① If the actual gap time of 10A flying shear passing through steel is less than the gap time threshold of 10A flying shear passing through steel, the gap time of 10A flying shear passing through steel is too short, and the 10A flying shear is controlled to start and break automatically;

[0065] ② If the actual gap time of 10A flying shear passing through steel is ≥ the gap time threshold of 10A flying shear passing through steel, then the gap time of 10A flying shear passing through steel is not too short;

[0066] 3-4-6) Compare the actual steel gap time of the steel billet passing through the 10B flying shear with the 10B flying shear steel gap time threshold to determine whether the 10B flying shear steel gap time is too short:

[0067] ① If the actual gap time of 10B flying shear passing through steel is less than the gap time threshold of 10B flying shear passing through steel, the gap time of 10B flying shear passing through steel is too short, and the 10B flying shear is controlled to start automatically breaking;

[0068] ② If the actual gap time of 10B flying shear passing through steel is ≥ the gap time threshold of 10B flying shear passing through steel, the gap time of 10B flying shear passing through steel is not too short.

[0069] Preferably, in step 3-4-1), the specific manner of dynamically adjusting the protection distance of each flying shear by using a plurality of steel-passing gap time thresholds includes:

[0070] ① Set the protection distance of 6A flying shear to: K1*L1;

[0071] Where, K1 is the signal protection coefficient of 6A flying shear, L1 is the distance from 3A pinch roller to 6A flying shear;

[0072] ②Set the protection distance of 6B flying shear to: K2*L2;

[0073] Where, K2 is the signal protection coefficient of 6B flying shear, L2 is the distance from 3B pinch roller to 6B flying shear;

[0074] ③Set the protection distance of 10A flying shear to: K3*L3;

[0075] Where K3 is the signal protection coefficient of 10A flying shear, L3 is the distance from finishing 2A to 10A flying shear;

[0076] ④Set the protection distance of 10B flying shear to: K4*L4;

[0077] Where K4 is the signal protection coefficient of 10B flying shear, and L4 is the distance from finishing 2B to 10B flying shear.

[0078] Preferably, the target gap time threshold value ranges from 3 to 4 seconds.

[0079] Preferably, the steel biting time threshold has a value range of 5 to 6 seconds.

[0080] The beneficial effects of the present invention are as follows:

[0081] ① The present invention can provide a continuous and stable steel delivery rhythm by setting a steel request time threshold, thereby reducing the slow steel delivery rhythm caused by manual sending of steel request signals and the idling time of the rolling mill due to waiting for the supply of steel billets, so that the rolling mill can maintain a high rolling speed and work efficiency, thereby improving production efficiency;

[0082] ② The present invention can monitor the state of the steel billet at the entrance of the 1# frame by setting a steel biting time threshold, thereby avoiding the steel billet from being detained at the entrance of the 1# frame for a long time due to abnormal conditions such as steel billet slippage, and preventing further impact of the abnormal conditions;

[0083] Based on the existing technology, although the working efficiency can be improved by reducing the gap time of 6# shear and 10# shear, that is, by shortening the actual gap time of 6# shear and 10# shear, the rolling rhythm can be directly accelerated. However, when the actual gap time of 6# shear and 10# shear is shortened to a certain extent, many problems are likely to occur, such as:

[0084] ① The heat detection signal before the 6A flying shear is protected by the heat detection signal before the 3A# pinch roller. The heat detection signal before the 6A flying shear will not be lost within T4 seconds (T4=0.8*L1 / V1, V1 is the speed of the 6A pinch roller) after the tail of the steel leaves the heat detection before the 3A pinch roller. If the rolling rhythm is increased to a certain extent, the tail of the previous steel will leave the heat detection before the 3A pinch roller for less than T4 seconds, and the next steel will arrive at the heat detection before the 3A pinch roller. In this case, the 6A flying shear will not be able to distinguish between the two steels and will not (cannot) execute the cutting command for the next steel, resulting in a steel pile accident.

[0085] ②The heat detection signal before the 6B flying shear is protected by the heat detection signal before the 3B pinch roller. The heat detection signal before the 6B flying shear will not be lost within T5 seconds (T5=0.8*L2 / V2, V2 is the speed of the 6B pinch roller) after the tail of the steel leaves the heat detection before the 3B pinch roller. If the rolling rhythm is increased to a certain extent, the tail of the previous steel will leave the heat detection before the 3B pinch roller for less than T5 seconds, and the next steel will arrive at the heat detection before the 3B pinch roller. In this case, the 6A# flying shear cannot distinguish between the two steels and will not (cannot) execute the cutting command for the next steel, resulting in a steel pile accident.

[0086] ③The 10A flying shear front heat detection signal is protected by the finishing rolling 2A front heat detection signal. Within T6 seconds (T6=0.8*L3 / V3, V3 is the 10A pinch roller speed) after the tail of the steel leaves the finishing rolling 2A front heat detection signal, the 10A flying shear front heat detection signal will not be lost. Increasing the rolling rhythm to a certain extent will cause the tail of the previous steel to leave the finishing rolling 2A front heat detection signal for less than T6 seconds, and the next steel will arrive at the finishing rolling 2A front heat detection. In this case, the 10A flying shear cannot distinguish that these are two steels, causing BBD1A and BBD2A to be unable to execute the tail braking command, resulting in the steel drilling cage accident at the tail of the hub.

[0087] ④The 10B flying shear pre-heat detection signal is protected by the finishing 2B pre-heat detection signal. Within T7 seconds (T7 = 0.8*L4 / V4, V4 is the 10B pinch roller speed) after the tail of the steel leaves the finishing 2B pre-heat detection signal, the 10B flying shear pre-heat detection signal will not be lost. Increasing the rolling rhythm to a certain extent will cause the tail of the previous steel to leave the finishing 2B pre-heat detection signal for less than T7 seconds, and the next steel will arrive at the finishing 2B pre-heat detection. In this case, the 10B flying shear cannot distinguish that these are two steels, causing BBD1B and BBD2B to be unable to execute the tail braking command, resulting in the steel drilling cage accident at the tail of the hub.

[0088] The present invention solves the above problems by adopting the following methods:

[0089] ①2-1) Set the signal protection coefficient K1 of 6A flying shear, and use the following formula to set the steel clearance time threshold T4 of 6A flying shear:

[0090] K1=(T3-0.5)*V1 / L1

[0091] T4=K1*L1 / V1

[0092] Where, K1 is the signal protection coefficient of 6A flying shear, T3 is the target gap time threshold, T4 is the steel gap time threshold of 6A flying shear, L1 is the distance from 3A pinch roller to 6A flying shear, and V1 is the real-time speed of 6A pinch roller;

[0093] This step is actually to change the fixed value of 0.8 in the gap time T4=0.8*L1 / V1 of the 6A flying shear to the variable K1, and the variable K1=(T3-0.5)*V1 / L1. According to different rolling rhythms, the protection distance of the heat inspection before the 6A flying shear is dynamically adjusted (the original 0.8*L1 is changed to K1*L1), to ensure that when the rolling rhythm is improved, the 6A flying shear will no longer cause steel accumulation because it cannot identify the front and rear two steels;

[0094] ②2-2) Set the signal protection factor K2 of the 6B flying shear and use the following formula to adjust the gap time of the 6B flying shear passing through the steel:

[0095] K2=(T3-0.5)*V2 / L2

[0096] T5=K2*L2 / V2

[0097] Where, K2 is the signal protection coefficient of 6B flying shear, T3 is the target gap time threshold, T5 is the steel gap time threshold of 6B flying shear, L2 is the distance from 3B pinch roller to 6B flying shear, and V2 is the real-time speed of 6B pinch roller;

[0098] This step is actually to change the fixed value of 0.8 in the gap time T5=0.8*L2 / V2 of the 6B flying shear to the variable K2, and the variable K2=(T3-0.5)*V2 / L2. According to different rolling rhythms, the protection distance of the heat inspection before the 6B flying shear is dynamically adjusted (the original 0.8*L2 is changed to K2*L2), to ensure that when the rolling rhythm is improved, the 6B flying shear will no longer cause steel accumulation due to the inability to identify the front and rear two steels;

[0099] ③2-3) Set the signal protection factor K3 of the 10A flying shear, and use the following formula to adjust the gap time of the 10A flying shear passing through the steel:

[0100] K3=(T3-0.5)*V3 / L3

[0101] T6=K3*L3 / V3

[0102] Where, K3 is the signal protection coefficient of 10A flying shear, T3 is the target gap time threshold, T6 is the steel gap time threshold of 10A flying shear, L3 is the distance from finishing 2A to 10A flying shear, and V3 is the real-time speed of 10A pinch roller;

[0103] This step is actually to change the fixed value of 0.8 in the gap time T6=0.8*L3 / V3 of the 10A flying shear to the variable K3, and the variable K3=(T3-0.5)*V3 / L3. According to different rolling rhythms, the protection distance of the heat inspection before the 10A flying shear is dynamically adjusted (the original 0.8*L3 is changed to K3*L3), to ensure that when the rolling rhythm is improved, the 10A flying shear will not be unable to identify the front and rear two steels, resulting in BBD1A and BBD2A being unable to execute the tail brake command, causing the steel to drill the cage at the tail of the hub.

[0104] ④2-4) Set the signal protection factor K4 of the 10A flying shear and use the following formula to calculate the gap time of the 10B flying shear passing through the steel:

[0105] K4=(T3-0.5)*V4 / L4

[0106] T7=K4*L4 / V4

[0107] Where, K4 is the signal protection coefficient of 10B flying shear, T3 is the target gap time threshold, T7 is the steel gap time threshold of 10B flying shear, L4 is the distance from finishing 2B to 10B flying shear, and V4 is the real-time speed of 10B pinch roller;

[0108] This step actually changes the fixed value of 0.8 in the gap time T7=0.8*L4 / V4 of 10B flying shear passing through steel to variable K4, and variable K4=(T3-0.5)*V4 / L4. According to different rolling rhythms, the protection distance of the heat inspection before 10B flying shear is dynamically adjusted (the original 0.8*L4 is changed to K4*L4) to ensure that when the rolling rhythm is improved, BBD1B and BBD2B will not be unable to execute the tail braking command due to the inability of 10B flying shear to identify the front and rear steels, causing the steel to drill into the cage at the tail of the hub.

[0109] The advantages of the present invention are as follows:

[0110] ① The present invention sets multiple time thresholds and compares them with the real-time steel-passing gap time of the corresponding frame. When the steel-passing gap time is too short, the steel billet can be broken to prevent the occurrence of steel slippage, steel piling, and drilling cage accidents at the tail of the rotating hub, which is conducive to the stability and continuity of the steel billet rolling production line, and can improve the yield rate of the steel billet and the service life of the equipment;

[0111] ② The present invention has developed a complete set of control logic, so that all links of the billet rolling production line are closely connected. While ensuring production safety, the rolling rhythm of the double-high bar hot delivery direct rolling process is accelerated as much as possible, thereby increasing the output of double-high bars, which helps to improve the production efficiency and production quality of the double-high bar hot delivery direct rolling process and enhance the competitiveness of the enterprise.

[0112] Glossary

[0113] Double high bar: usually refers to a bar production line with the characteristics of high output and high quality.

[0114] Hot delivery: refers to sending the newly produced, high-temperature billet directly to the steel rolling process, rather than cooling it first and then heating it.

[0115] Steel gap time: refers to the time interval between two adjacent billets (or rolled products) passing through the rolling mill during the hot delivery and direct rolling of double-high bars. It reflects the rhythm and continuity of the rolling process and is one of the important indicators for measuring the efficiency and stability of the production line.

[0116] Continuous casting: The full name is continuous casting of steel. It is a steel production process that continuously casts molten steel into billets with certain shapes and specifications through specific equipment and processes. Continuous casting: The full name is continuous casting of steel (or continuous casting). It is a process that continuously casts molten steel (or other molten metal) through a set of special equipment.

[0117] Rolling line HMI: It is a human-machine interface system specially used for monitoring and controlling the rolling production process in the rolling line (rolling production line) environment. It connects various equipment in the rolling line, such as rolling mills, conveying devices, heating furnaces, etc.

[0118] Hot-feed direct rolling roller table: It is a device used to transport continuous casting billets in the steel production process. It consists of a series of rollers, which are usually driven by motors to transport the continuous casting billets forward. When the continuous casting billets come out of the continuous casting machine, the temperature is still very high. The hot-feed direct rolling roller table can directly transport the hot continuous casting billets to the rolling mill for rolling without the need for cooling and reheating in the traditional process.

[0119] Flying shear: A device used to shear moving rolled products. In a rolling production line, it can quickly and accurately shear continuously moving steel billets, aluminum materials, and other metal materials (rolled products) according to a preset length.

[0120] Slippery steel: refers to the situation that during the rolling process, the steel billet does not pass through the rollers according to the normal rolling path and speed, but slides on the surface of the rollers and cannot be bitten and rolled normally.

[0121] Steel pile-up: refers to the phenomenon that steel billets or steel products pile up between or inside rolling mills during the rolling process. For example, in the continuous rolling link of the double-high bar direct rolling process, the steel billets fail to pass through the rolling mill at the normal rolling speed and rhythm, and pile up in front of a rolling mill or between rolling mills, forming a disordered pile-up state of the steel billets.

[0122] The cage drilling accident at the tail of the hub refers to the abnormal situation that causes the BBD in front of the hub (i.e. the rod tail brake, its function is to reduce the speed of high-speed running steel, including BBD1A, BBD2A, BBD1B, BBD2B, BBD1A, BBD2A are the 1# and 2# rod tail brakes of line A respectively, BBD1B, BBD2B are the 1# and 2# rod tail brakes of line B respectively) to be unable to issue a command to hold the high-speed moving steel and reduce the speed, resulting in the steel entering the hub and following the rotation, the steel directly flies into the cage behind the tail of the hub, causing the hub to fail to work normally, and the detection signal at the tail of the hub will chain the entire line to issue a break command.

[0123] Steel request time: that is, the countdown time for steel request, specifically refers to the interval time when the rolling mill sends the steel request signal to the continuous casting machine.

[0124] Steel biting time: refers to the interval time from when the 1# rack recognizes the steel billet through the heat detection device to when it bites the steel billet.

[0125] Target gap time: refers to the instantaneous interval time from when the 6# rack recognizes the first steel billet to when it recognizes the second steel billet (Beijing time, accurate to ms), which can be adjusted in real time according to production process requirements.

[0126] Signal protection coefficient: an intermediate parameter used to adjust the shortest allowable steel clearance time of the flying shear.

[0127] Steel passing gap time: the instantaneous interval time from when the flying shear recognizes the first steel billet to when it recognizes the second steel billet (Beijing time, accurate to ms). BRIEF DESCRIPTION OF THE DRAWINGS

[0128] Figure 1 is a flow chart of the method of the present invention;

[0129] Figure 2 This is a schematic diagram of the hardware structure of this embodiment;

[0130] Figure 3 For this embodiment, the steel control flow chart is shown;

[0131] Figure 4 This is a schematic diagram of the logic control of the dynamic adjustment of the hot shear protection distance before the 6# and 10# flying shears in this embodiment;

[0132] Figure 5 This is the layout diagram of the double high rod equipment in this embodiment. DETAILED DESCRIPTION

[0133] like Figures 1 to 5 As shown, a control method for improving the rolling rhythm of a double-high bar direct rolling process comprises the following steps:

[0134] 1) Set the steel-requiring time threshold, steel-biting time threshold, and target gap time threshold;

[0135] 2) setting a number of signal protection coefficients according to the target gap time threshold, and setting the steel gap time threshold of each flying shear according to the signal protection coefficient;

[0136] 3) The various time thresholds set in step 1) and step 2) are used as control parameters to roll the steel billet in the double-high bar direct rolling process.

[0137] The above steps are used to control the rolling rhythm of the double-high bar direct rolling process, and an example is as follows:

[0138] 1) Set the steel demand time threshold T1 (steel demand countdown time), steel bite time threshold, and target gap time threshold T3 (6# rack steel gap time) on the rolling line HMI screen;

[0139] In this embodiment, the target gap time threshold T3 has a value range of 3 to 4 seconds, and the steel biting time threshold has a value range of 5 to 6 seconds.

[0140] The steel-demanding time threshold T1, steel-biting time threshold, and target gap time threshold T3 can all be flexibly set by the double-high bar operator in the open parameter setting window of the HMI operation interface, and the specific value range is flexibly adjusted by the double-high bar operator according to different rolling specifications. Among them, the target gap time threshold T3 is controlled within a range close to 3s but not less than 3s, and the steel-demanding time threshold is set to 30±1s more than the target gap time threshold T3, and then adjusted according to the actual rolling conditions of multiple billets (generally 2 to 3 billets) until the actual steel-passing interval time of the 6# frame is as close to T3 as possible but not less than T3. In other words, the steel-demanding time threshold is an empirical value determined through multiple calibration experiments, and the value range is 3 to 4s (and the values ​​of time T1 and time T3 are made as close as possible). Similarly, the steel-biting time threshold is also an empirical value determined through multiple calibration experiments after setting the target gap time threshold.

[0141] This embodiment adjusts the steel demand time threshold T1 through the target gap time threshold T3 to achieve the purpose of stable control of the continuous casting delivery rhythm, and takes measures such as 1# frame alarm, steel demand blocking, and 1# flying shear automatic breaking to ensure that after the steel gap is too short, the rolling line can still roll normally. Control measures are taken to balance the steel demand of the double high bar rolling mill and the continuous casting steel delivery rhythm, which can ensure that the continuous casting steel delivery rhythm is stable and continuous, and there will be no problems such as steel jamming and slow steel delivery rhythm due to the coordination problem between steel demand and steel delivery, so as to achieve the purpose of improving the rolling rhythm, reducing the occurrence rate of production accidents, improving the yield rate, and increasing the service life of equipment.

[0142] 2) According to the target gap time threshold T3, a number of signal protection coefficients (protection signal coefficients) are set, and the specific method of setting the steel gap time threshold of each flying shear according to the signal protection coefficient includes:

[0143] 2-1) Set the signal protection coefficient K1 of the 6A flying shear, and use the following formula to set the steel clearance time threshold T4 of the 6A flying shear:

[0144] K1=(T3-0.5)*V1 / L1

[0145] T4=K1*L1 / V1

[0146] Where, K1 is the signal protection coefficient of 6A flying shear, T3 is the target gap time threshold, T4 is the steel gap time threshold of 6A flying shear, L1 is the distance from 3A pinch roller to 6A flying shear, and V1 is the real-time speed of 6A pinch roller;

[0147] 2-2) Set the signal protection factor K2 of the 6B flying shear and use the following formula to adjust the gap time of the 6B flying shear:

[0148] K2=(T3-0.5)*V2 / L2

[0149] T5=K2*L2 / V2

[0150] Where, K2 is the signal protection coefficient of 6B flying shear, T3 is the target gap time threshold, T5 is the steel gap time threshold of 6B flying shear, L2 is the distance from 3B pinch roller to 6B flying shear, and V2 is the real-time speed of 6B pinch roller;

[0151] 2-3) Set the signal protection factor K3 of the 10A flying shear and use the following formula to adjust the gap time of the 10A flying shear passing through the steel:

[0152] K3=(T3-0.5)*V3 / L3

[0153] T6=K3*L3 / V3

[0154] Where, K3 is the signal protection coefficient of 10A flying shear, T3 is the target gap time threshold, T6 is the steel gap time threshold of 10A flying shear, L3 is the distance from finishing 2A to 10A flying shear, and V3 is the real-time speed of 10A pinch roller;

[0155] 2-4) Set the signal protection factor K4 of the 10A flying shear and use the following formula to calculate the steel clearance time of the 10B flying shear:

[0156] K4=(T3-0.5)*V4 / L4

[0157] T7=K4*L4 / V4

[0158] Wherein, K4 is the signal protection coefficient of 10B flying shear, T3 is the target gap time threshold, T7 is the steel gap time threshold of 10B flying shear, L4 is the distance from finishing 2B to 10B flying shear, and V4 is the real-time speed of 10B pinch roller.

[0159] 3) The time thresholds set in step 1) and step 2) are used as additional control parameters (i.e., in addition to the conventional parameters of the double-high bar direct rolling process), and the specific method of rolling the steel billet in the double-high bar direct rolling process includes:

[0160] 3-1) Using the steel demand time threshold T1 to control the steel delivery rhythm, the specific methods include:

[0161] 3-1-1) The continuous casting machine receives the steel request signal from the rolling mill and performs steelmaking. After steelmaking is completed, it sends a steel delivery signal to the hot-feeding straight rolling roller table;

[0162] 3-1-2) The hot delivery straight rolling roller receives the steel sending signal, sends a signal prohibiting steel request to the rolling mill, and transports the steel billet from the continuous casting machine to the rolling mill within the steel request time threshold T1;

[0163] 3-1-3) When the tail of the billet leaves the hot delivery straightening roller for heat inspection, the hot delivery straight rolling roller table sends a signal to the rolling mill to release the prohibition of steel demand;

[0164] 3-1-4) The rolling mill receives the signal for lifting the prohibition on steel demand and waits. When the waiting time is equal to the steel demand time threshold T1, a steel demand signal is issued.

[0165] In this embodiment, the steel demand time threshold T1 is used in the form of a countdown, that is, after the hot delivery direct rolling roller receives the continuous casting steel supply signal, T1 is triggered to start the countdown, and at the same time a signal prohibiting steel demand is sent to the continuous casting. When the tail of the steel leaves the hot inspection in front of the hot delivery direct rolling straightening roller, the signal prohibiting steel demand is released, triggering the rolling mill steel demand countdown T1. When the preset countdown time T1 is reached, the continuous casting is allowed to continue to deliver steel to the double-high bars.

[0166] 3-2) Using the steel biting time threshold to determine whether the billet is slipping, the specific methods include:

[0167] 3-2-1) Calculate the time when the entrance of the 1# rack recognizes the head of the steel billet but does not bite the steel;

[0168] 3-2-2) comparing the time calculated in step 3-3-1) with the steel biting time threshold to determine whether the steel billet is slipping;

[0169] ① If the time when the billet head is identified but not bitten is less than the steel biting time threshold, the billet does not slip at the entrance of the 1# rack;

[0170] ② If the time of identifying the head of the billet but not biting the steel is greater than the steel biting time threshold, the steel slips at the entrance of the 1# frame, triggering the HMI and buzzer to send out an alarm signal, indicating that the steel slips at the entrance of the 1# frame. The hot-feed straight rolling roller sends a signal prohibiting steel from being required to the rolling mill, and the 1# and 2# rollers stop coming out of the furnace. The 3# roller reverses to reverse and remove the slipping steel.

[0171] 3-3) Using the target gap time threshold T3 to determine whether there is a risk of too short gap time, the specific methods include:

[0172] 3-3-1) Calculate the actual steel gap time of the steel billet passing through the 1# rack and the 6# rack respectively;

[0173] 3-3-2) Compare the actual steel gap time of the steel billet passing through the 1# rack with the target gap time threshold T3 to determine whether the steel gap time of the 1# rack is too short:

[0174] ① If the actual steel-passing gap time of the 1# rack is less than the target gap time threshold T3-0.5, there is a risk that the steel billet may have a too short steel-passing gap time, and the buzzer alarm sends out an alarm signal;

[0175] ② If the actual steel-passing gap time of the 1# rack is ≥ the target gap time threshold T3-0.5, there is no risk of the steel billet having a too short steel-passing gap time;

[0176] 3-3-3) Compare the actual steel gap time of the steel billet passing through the 6# rack with the target gap time threshold T3 to determine whether the steel billet needs to be broken:

[0177] ① If the actual steel-passing gap time of the 6# frame is less than the target gap time threshold T3, the 1# flying shear is controlled to start automatic breaking;

[0178] ② If the actual steel-passing gap time of the 6# rack is ≥ the target gap time threshold T3, the steel billet will not be automatically broken.

[0179] 3-4) The specific methods of dynamically adjusting the protection distance of each flying shear by using several steel-passing gap time thresholds and judging whether the steel-passing gap time of each flying shear is too short include:

[0180] 3-4-1) Use several steel-passing gap time thresholds to dynamically adjust the protection distance of each flying shear. The specific methods include:

[0181] ① Set the protection distance of 6A flying shear to: K1*L1;

[0182] Where, K1 is the signal protection coefficient of 6A flying shear, L1 is the distance from 3A pinch roller to 6A flying shear;

[0183] ②Set the protection distance of 6B flying shear to: K2*L2;

[0184] Where, K2 is the signal protection coefficient of 6B flying shear, L2 is the distance from 3B pinch roller to 6B flying shear;

[0185] ③Set the protection distance of 10A flying shear to: K3*L3;

[0186] Where K3 is the signal protection coefficient of 10A flying shear, L3 is the distance from finishing 2A to 10A flying shear;

[0187] ④Set the protection distance of 10B flying shear to: K4*L4;

[0188] Where K4 is the signal protection coefficient of 10B flying shear, and L4 is the distance from finishing 2B to 10B flying shear.

[0189] In this embodiment, the protection distance of the heat inspection before the 6# and 10# flying shears is dynamically adjusted (the original 0.8*L is changed to K*L), which can ensure that when the rolling rhythm is improved, there will be no accidents such as steel piling and cage drilling due to the inability of the 6# and 10# flying shears to identify the front and rear two steels, thereby achieving the purpose of improving the rolling rhythm, reducing the occurrence rate of production accidents, and improving the yield rate.

[0190] 3-4-2) Calculate the actual steel gap time of the steel billet passing through 6A flying shear, 6B flying shear, 10A flying shear and 10B flying shear respectively;

[0191] 3-4-3) Compare the actual steel gap time of the steel billet passing through the 6A flying shear with the 6A flying shear steel gap time threshold to determine whether the 6A flying shear steel gap time is too short:

[0192] ① If the actual gap time of the 6A flying shear passing through the steel is less than the gap time threshold of the 6A flying shear passing through the steel, the gap time of the 6A flying shear passing through the steel is too short, and the 6A flying shear is controlled to start automatically breaking;

[0193] ② If the actual gap time of 6A flying shear passing through steel is ≥ the gap time threshold of 6A flying shear passing through steel, the gap time of 6A flying shear passing through steel is not too short;

[0194] 3-4-4) Compare the actual steel gap time of the steel billet passing through the 6B flying shear with the 6B flying shear steel gap time threshold to determine whether the 6B flying shear steel gap time is too short:

[0195] ① If the actual gap time of 6B flying shear passing through steel is less than the gap time threshold of 6B flying shear passing through steel, the gap time of 6B flying shear passing through steel is too short, and the 6B flying shear is controlled to start automatically breaking;

[0196] ② If the actual clearance time of the 6B flying shear passing the steel is ≥ the clearance time threshold of the 6B flying shear passing the steel, the clearance time of the 6A flying shear passing the steel is not too short;

[0197] 3-4-5) Compare the actual steel gap time of the steel billet passing through the 10A flying shear with the 10A flying shear steel gap time threshold to determine whether the 10A flying shear steel gap time is too short:

[0198] ① If the actual gap time of 10A flying shear passing through steel is less than the gap time threshold of 10A flying shear passing through steel, the gap time of 10A flying shear passing through steel is too short, and the 10A flying shear is controlled to start and break automatically;

[0199] ② If the actual gap time of 10A flying shear passing through steel is ≥ the gap time threshold of 10A flying shear passing through steel, the gap time of 10A flying shear passing through steel is not too short;

[0200] 3-4-6) Compare the actual steel gap time of the steel billet passing through the 10B flying shear with the 10B flying shear steel gap time threshold to determine whether the 10B flying shear steel gap time is too short:

[0201] ① If the actual gap time of 10B flying shear passing through steel is less than the gap time threshold of 10B flying shear passing through steel, the gap time of 10B flying shear passing through steel is too short, and the 10B flying shear is controlled to start automatically breaking;

[0202] ② If the actual gap time of 10B flying shear passing through steel is ≥ the gap time threshold of 10B flying shear passing through steel, the gap time of 10B flying shear passing through steel is not too short.

[0203] In this embodiment, the operator of the double high bar can stop the breaking at any time according to the breaking situation of the billet by pulling the button on the operation table in the control room, and continue to roll the billet normally, which can improve the yield rate. In addition, when the 1# flying shear, 6# flying shear, and 10# flying shear start automatic breaking, the specific breaking length is determined by the operator of the double high bar.

[0204] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification made to the present invention by those skilled in the art without departing from the spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A control method for improving the rolling rhythm of a double-high bar direct rolling process, characterized in that: The following steps are involved: 1) Set the steel-requiring time threshold, steel-biting time threshold, and target gap time threshold; 2) setting a number of signal protection coefficients according to the target gap time threshold, and setting the steel gap time threshold of each flying shear according to the signal protection coefficient; 3) Using the multiple time thresholds set in step 1) and step 2) as control parameters, the steel billet is rolled in a double-high rod direct rolling process.

2. A control method for improving the rolling rhythm of a double-high bar direct rolling process according to claim 1, characterized in that: In step 2), a plurality of signal protection coefficients are set according to the target gap time threshold, and the specific method of setting the steel gap time threshold of each flying shear according to the signal protection coefficient includes: 2-1) Set the signal protection coefficient K1 of the 6A flying shear, and use the following formula to set the steel clearance time threshold T4 of the 6A flying shear: K1=(T3-0.5)*V1 / L1 T4=K1*L1 / V1 Where, K1 is the signal protection coefficient of 6A flying shear, T3 is the target gap time threshold, T4 is the steel gap time threshold of 6A flying shear, L1 is the distance from 3A pinch roller to 6A flying shear, and V1 is the real-time speed of 6A pinch roller; 2-2) Set the signal protection factor K2 of the 6B flying shear and use the following formula to adjust the gap time of the 6B flying shear: K2=(T3-0.5)*V2 / L2 T5=K2*L2 / V2 Where, K2 is the signal protection coefficient of 6B flying shear, T3 is the target gap time threshold, T5 is the steel gap time threshold of 6B flying shear, L2 is the distance from 3B pinch roller to 6B flying shear, and V2 is the real-time speed of 6B pinch roller; 2-3) Set the signal protection factor K3 of the 10A flying shear and use the following formula to adjust the gap time of the 10A flying shear passing through the steel: K3=(T3-0.5)*V3 / L3 T6=K3*L3 / V3 Where, K3 is the signal protection coefficient of 10A flying shear, T3 is the target gap time threshold, T6 is the steel gap time threshold of 10A flying shear, L3 is the distance from finishing 2A to 10A flying shear, and V3 is the real-time speed of 10A pinch roller; 2-4) Set the signal protection factor K4 of the 10A flying shear and use the following formula to calculate the steel clearance time of the 10B flying shear: K4=(T3-0.5)*V4 / L4 T7=K4*L4 / V4 Wherein, K4 is the signal protection coefficient of 10B flying shear, T3 is the target gap time threshold, T7 is the steel gap time threshold of 10B flying shear, L4 is the distance from finishing 2B to 10B flying shear, and V4 is the real-time speed of 10B pinch roller.

3. A control method for improving the rolling rhythm of a double-high bar direct rolling process according to claim 1, characterized in that: In step 3), the multiple time thresholds set in step 1) and step 2) are used as control parameters, and the specific method of rolling the steel billet in the double high bar direct rolling process includes: 3-1) Use the steel demand time threshold to control the steel delivery rhythm; 3-2) Using the steel biting time threshold to determine whether the billet is slipping; 3-3) Using the target gap time threshold to determine whether there is a risk of too short gap time during steelmaking; 3-4) Use several steel-passing gap time thresholds to dynamically adjust the protection distance of each flying shear, and determine whether the steel-passing gap time of each flying shear is too short.

4. A control method for improving the rolling rhythm of a double-high bar direct rolling process according to claim 3, characterized in that: In step 3-1), the specific method of controlling the steel production rhythm by using the steel demand time threshold includes: 3-1-1) The continuous casting machine receives the steel request signal from the rolling mill and performs steelmaking. After steelmaking is completed, it sends a steel delivery signal to the hot-feeding straight rolling roller table; 3-1-2) The hot delivery straight rolling roller receives the steel sending signal, sends a signal prohibiting steel request to the rolling mill, and transports the steel billet from the continuous casting machine to the rolling mill within the steel request time threshold; 3-1-3) When the tail of the billet leaves the hot delivery straightening roller for heat inspection, the hot delivery straight rolling roller table sends a signal to the rolling mill to release the prohibition of steel demand; 3-1-4) The rolling mill receives the signal for lifting the prohibition on steel demand and waits. When the waiting time is equal to the steel demand time threshold, a steel demand signal is issued.

5. A control method for improving the rolling rhythm of a double-high bar direct rolling process according to claim 3, characterized in that: In step 3-2), the specific method of using the steel biting time threshold to determine whether the steel billet is slipping includes: 3-2-1) Calculate the time when the entrance of the 1# rack recognizes the head of the steel billet but does not bite the steel; 3-2-2) comparing the time calculated in step 3-3-1) with the steel biting time threshold to determine whether the steel billet is slipping; ① If the time when the billet head is identified but not bitten is less than the steel biting time threshold, the billet does not slip at the entrance of the 1# rack; ② If the time of identifying the head of the billet but not biting the steel is greater than the steel biting time threshold, the steel slips at the entrance of the 1# frame, an alarm signal is issued, and the hot-feed straight rolling roller sends a signal prohibiting steel from being required to the rolling mill. The 1# and 2# rollers stop coming out of the furnace, and the 3# roller reverses to reverse and remove the slipping steel.

6. A control method for improving the rolling rhythm of a double-high bar direct rolling process according to claim 3, characterized in that: In step 3-3), the specific method of using the target gap time threshold to determine whether there is a risk of too short gap time for steel passing includes: 3-3-1) Calculate the actual steel gap time of the steel billet passing through the 1# rack and the 6# rack respectively; 3-3-2) Compare the actual steel gap time of the steel billet passing through the 1# rack with the target gap time threshold to determine whether the steel gap time of the 1# rack is too short: ① If the actual steel-passing gap time of the 1# rack is less than the target gap time threshold - 0.5, there is a risk that the steel billet may have a too short steel-passing gap time, and an alarm signal is issued; ② If the actual steel-passing gap time of the 1# rack is ≥ the target gap time threshold - 0.5, there is no risk of the steel billet having a too short steel-passing gap time; 3-3-3) Compare the actual gap time of the steel billet passing through the 6# rack with the target gap time threshold to determine whether the steel billet needs to be broken: ① If the actual steel-passing gap time of the 6# frame is less than the target gap time threshold, the 1# flying shear is controlled to start automatic breaking; ② If the actual steel gap time of the 6# rack is ≥ the target gap time threshold, the steel billet will not be automatically broken.

7. A control method for improving the rolling rhythm of a double-high bar direct rolling process according to claim 1, characterized in that: In step 3-4), the specific method of dynamically adjusting the protection distance of each flying shear by using a plurality of steel-passing gap time thresholds and judging whether the steel-passing gap time of each flying shear is too short includes: 3-4-1) Dynamically adjust the protection distance of each flying shear using several steel-passing gap time thresholds; 3-4-2) Calculate the actual steel gap time of the steel billet passing through 6A flying shear, 6B flying shear, 10A flying shear and 10B flying shear respectively; 3-4-3) Compare the actual steel gap time of the steel billet passing through the 6A flying shear with the 6A flying shear steel gap time threshold to determine whether the 6A flying shear steel gap time is too short: ① If the actual gap time of the 6A flying shear passing through the steel is less than the gap time threshold of the 6A flying shear passing through the steel, the gap time of the 6A flying shear passing through the steel is too short, and the 6A flying shear is controlled to start automatically breaking; ② If the actual gap time of 6A flying shear passing through steel is ≥ the gap time threshold of 6A flying shear passing through steel, the gap time of 6A flying shear passing through steel is not too short; 3-4-4) Compare the actual steel gap time of the steel billet passing through the 6B flying shear with the 6B flying shear steel gap time threshold to determine whether the 6B flying shear steel gap time is too short: ① If the actual gap time of 6B flying shear passing steel is less than the gap time threshold of 6B flying shear passing steel, the gap time of 6B flying shear passing steel is too short, and the 6B flying shear is controlled to start automatically breaking; ② If the actual gap time of 6B flying shear passing steel is greater than or equal to the gap time threshold of 6B flying shear passing steel, the gap time of 6A flying shear passing steel is not too short; 3-4-5) Compare the actual steel gap time of the steel billet passing through the 10A flying shear with the 10A flying shear steel gap time threshold to determine whether the 10A flying shear steel gap time is too short: ① If the actual gap time of 10A flying shear passing through steel is less than the gap time threshold of 10A flying shear passing through steel, the gap time of 10A flying shear passing through steel is too short, and the 10A flying shear is controlled to start and break automatically; ② If the actual gap time of 10A flying shear passing through steel is ≥ the gap time threshold of 10A flying shear passing through steel, then the gap time of 10A flying shear passing through steel is not too short; 3-4-6) Compare the actual steel gap time of the steel billet passing through the 10B flying shear with the 10B flying shear steel gap time threshold to determine whether the 10B flying shear steel gap time is too short: ① If the actual gap time of 10B flying shear passing through steel is less than the gap time threshold of 10B flying shear passing through steel, the gap time of 10B flying shear passing through steel is too short, and the 10B flying shear is controlled to start automatically breaking; ② If the actual gap time of 10B flying shear passing through steel is ≥ the gap time threshold of 10B flying shear passing through steel, the gap time of 10B flying shear passing through steel is not too short.

8. A control method for improving the rolling rhythm of a double-high bar direct rolling process according to claim 7, characterized in that: In step 3-4-1), the specific method of dynamically adjusting the protection distance of each flying shear by using several steel-passing gap time thresholds includes: ① Set the protection distance of 6A flying shear to: K1*L1; Where, K1 is the signal protection coefficient of 6A flying shear, L1 is the distance from 3A pinch roller to 6A flying shear; ②Set the protection distance of 6B flying shear to: K2*L2; Where, K2 is the signal protection coefficient of 6B flying shear, L2 is the distance from 3B pinch roller to 6B flying shear; ③Set the protection distance of 10A flying shear to: K3*L3; Where K3 is the signal protection coefficient of 10A flying shear, L3 is the distance from finishing 2A to 10A flying shear; ④Set the protection distance of 10B flying shear to: K4*L4; Where K4 is the signal protection coefficient of 10B flying shear, and L4 is the distance from finishing 2B to 10B flying shear.

9. A control method for improving the rolling rhythm of a double-high bar direct rolling process according to claim 1, characterized in that: The target gap time threshold value ranges from 3 to 4 seconds.

10. A control method for improving the rolling rhythm of a double-high bar direct rolling process according to claim 1, characterized in that: The steel biting time threshold has a value range of 5 to 6 seconds.

Images