Automatic steel charging system and method for heating furnace

Abstract

The invention relates to an automatic steel charging system and method for a heating furnace, and belongs to the technical field of metallurgical industry automation control. According to the technical scheme, when a signal of a billet head or a billet tail of a billet is detected by a furnace door north side range finder (2011) and a furnace door south side range finder (2012), a steel loading roller way automatically runs at a low speed, and the billet is adjusted to be arranged between the furnace door north side range finder and the furnace door south side range finder; and after the furnace door is adjusted to the middle of the steel charging furnace door, the furnace door north-side range finder and the furnace door south-side range finder do not detect steel billet signals, the roller way speed of the steel charging roller way is reduced to 0 and lasts for 1 second, steel billet material flow and steel billet numbers are tracked in place, and after a heating furnace allows steel charging signals to be given, the steel charging machine automatically charges steel. The device has the beneficial effects that the device is suitable for an end-in and end-out heating furnace production mode, automatic, efficient and safe charging of steel billets is achieved through accurate positioning of the distance measuring instrument, intelligent control of the PLC, cooperative action of the steel charging arm and interlocking of the furnace door, and the production stability and the automation level are improved.

Description

Technical Field

[0001] The invention relates to a system and method for automatically charging steel into a heating furnace, belonging to the technical field of metallurgical industry automation control. Background Art

[0002] In the metallurgical industry, the heating furnace is a key equipment in the steel rolling production line, which is used to heat the steel billets. The traditional steel loading method mainly relies on manual operation or semi-automatic equipment, and has the following problems: 1. Low positioning accuracy: Manual adjustment of the position of the steel billet is prone to deviation, which makes it impossible for the steel billet to enter the furnace accurately, affecting the uniformity of heating. 2. Poor coordination of the furnace door: The steel loading action is not synchronized with the opening and closing of the furnace door, which may cause heat loss in the furnace or the risk of equipment collision. 3. Insufficient degree of automation: Relying on manual intervention, production efficiency is low, and there are safety hazards. 4. Lack of intelligent interlocking: The steel loading process has not been deeply integrated with the material flow tracking, furnace number management, speed control and other systems of the production line, affecting the overall stability.

[0003] Chinese patent application 201410155432.X discloses a “system and method for automatic steel loading positioning in a heating furnace”, which uses two distance meters to detect the presence or absence of signals from the billet head and tail, changes the roller speed, and uses the code value counting of the code disk to perform positioning. The distance meter and the code disk are involved in the entire positioning process. Chinese patent 201610087341.6 discloses a “method and system for automatic positioning of slabs in a heating furnace”, which uses 6 laser phototubes and code disks installed on the furnace top. The signal of the billet head is measured by the laser phototube, and the speed of the cantilever roller is continuously adjusted. The code disk continuously feeds back the motor speed to finally complete the positioning. The phototube and code disk are involved in the entire process, and three distance meters are used to correct the billet. The problem with the existing technology is that the above two patents are both applicable to heating furnaces using cantilever rollers, and cannot be applied to the end-in-end-out heating furnace production mode. The end-in-end-out heating furnace production mode: the steel loading side of the heating furnace (see Figure 1 ) consists of a steel-charging roller conveyor, a steel-charging machine and a steel-charging furnace door, wherein the steel-charging furnace door is equivalent to an entire furnace wall. After the steel-charging roller conveyor transports the steel billet to the designated position, the steel-charging furnace door opens, and the steel-charging machine sends the entire steel billet into the heating furnace. The stepping beam moves and gradually transports the steel billet to the steel-discharging side. The working principle of the steel-discharging side is the same as that of the steel-charging side. The steel-discharging furnace door opens as a whole, and the steel-discharging machine lifts the steel billet out and places it on the steel-discharging roller conveyor. The end-in-end-out heating furnace production mode is different from the working mode of the heating furnace with cantilever rollers. The steel billet is positioned on the steel-charging roller conveyor outside the furnace. After positioning is completed, the steel-charging machine places the steel billet into the heating furnace. For the heating furnace with cantilever rollers, the steel billet directly enters the cantilever roller inside the furnace from the steel-charging roller conveyor and is directly positioned inside the furnace. There is no mature existing technology for automatic steel loading in the end-in-end-out heating furnace production mode. It is necessary to develop a system and method for automatic steel loading of heating furnaces to realize automated production of end-in-end-out heating furnaces. Summary of the Invention

[0004] The purpose of the present invention is to provide an automatic steel loading system and method for a heating furnace, which is suitable for an end-in-end-out heating furnace production mode. Through precise positioning by a rangefinder and PLC control, an alarm is given for excessively long steel billets and the system is processed to prevent the furnace wall from being scratched during the loading process, thereby causing accidents. The system realizes automatic, efficient and safe loading of steel billets, improves production stability and automation level, and solves the above-mentioned technical problems existing in the background technology.

[0005] The technical solution of the present invention is: An automatic steel loading system for a heating furnace comprises a steel tapping machine, a steel tapping roller table, a steel tapping furnace door, a steel loading furnace door, a steel loading roller table, a steel loading machine, a heating furnace, a rangefinder on the north side of the furnace door, a rangefinder on the south side of the furnace door, a positioning encoder, a cross-beam detection, a host computer and a PLC. A steel loading furnace door and a steel tapping furnace door are respectively arranged on the east and west sides of the heating furnace. The steel loading furnace door and the steel tapping furnace door are respectively matched with a steel loading roller table and a steel tapping roller table. A steel loading machine and a steel tapping machine are respectively arranged on the steel loading roller table and the steel tapping roller table. The steel loading roller tables are arranged from south to north. A rangefinder on the south side of the furnace door and a rangefinder on the north side of the furnace door are respectively set next to the steel loading rollers on the north and south sides of the steel furnace door, which are used to detect the length of the steel billets on the steel loading rollers; a positioning encoder is provided on the steel loading roller, and a through-beam detector is provided next to the steel loading furnace door. The steel billets on the steel loading rollers are positioned by the positioning encoder and the through-beam detector. The steel loading rollers are driven by a motor drive device, and the rangefinder on the north side of the furnace door, the rangefinder on the south side of the furnace door, the positioning encoder, the through-beam detector and the motor drive device are controlled and processed by PLC and the host computer.

[0006] A walking beam is provided in the furnace wall of the heating furnace.

[0007] A method for automatically loading steel into a heating furnace, using the above system, comprises the following steps: a steel loading roller is used to carry and transport the steel billet to be heated to the steel loading position of the end-in and end-out heating furnace; first, after the steel head of the steel billet is detected by radiographic inspection, the steel billet is positioned by a positioning encoder; the positioning encoder has a disadvantage, that is, when encountering cold or bent billets, the positioning of some steel billets may be inaccurate due to the different friction coefficients between the steel billet and the roller, resulting in slippage; after the positioning encoder is positioned, if the steel billet position is inaccurate, the distance meter on the north side of the furnace door and the distance meter on the south side of the furnace door are used to measure the position of the steel billet. The instrument performs secondary positioning: if the distance meter on the north side of the furnace door detects the billet signal, the steel loading roller will rotate until the signal from the distance meter on the north side of the furnace door disappears, and the steel loading roller will stop rotating; if the distance meter on the south side of the furnace door detects the billet signal, the steel loading roller will rotate until the signal from the distance meter on the south side of the furnace door disappears, and the steel loading roller will stop rotating to ensure that the billet is between the distance meter on the north side of the furnace door and the distance meter on the south side of the furnace door; the distance meter on the north side of the furnace door and the distance meter on the south side of the furnace door detect whether the billet position is appropriate. If the billet is positioned in the middle of the charging furnace door, the roller speed of the steel loading roller |v|< 0.1m / s and stable for 1 second; at the same time, the heating furnace sends a signal to allow steel loading. When the conditions are met, the furnace door collaborative control unit of the upper computer opens the steel loading furnace door, and the steel loader automatically loads steel. After the steel loading is completed, the steel loader returns to its original position, the steel loading furnace door closes, and waits for the next billet; when the detected billet exceeds the standard length, the distance meter on the north side of the furnace door and the distance meter on the south side of the furnace door receive signals at the same time, and an alarm signal appears on the HMI screen of the upper computer's operating console. The steel loader will not automatically load steel to avoid the billet scraping the furnace wall and causing a greater accident.

[0008] When the head or tail of the billet is detected by the distance meter on the north side of the furnace door and the distance meter on the south side of the furnace door, the loading roller automatically runs at a low speed and adjusts the billet to be placed between the distance meter on the north side of the furnace door and the distance meter on the south side of the furnace door; after adjusting to the middle of the loading furnace door, the distance meter on the north side of the furnace door and the distance meter on the south side of the furnace door will not detect the billet signal, the roller speed of the loading roller is reduced to 0 and lasts for 1s, the billet flow and billet number are tracked in place, and after the heating furnace allows the loading signal, the loader automatically loads the steel.

[0009] If an alarm signal appears on the HMI screen of the upper computer console, the operator needs to manually confirm whether the length of the steel billet exceeds the standard. If it is confirmed that it exceeds the standard, the operator switches to manual loading of steel.

[0010] The positioning encoder of the present invention does not need to participate in secondary positioning. No matter it is a cold billet, a hot billet or a bent billet, as long as the distance meter on the north side of the furnace door and the distance meter on the south side of the furnace door do not send out a steel signal, steel can be loaded effectively.

[0011] The beneficial effects of the present invention are: it is suitable for the end-in-end-out heating furnace production mode, and through precise positioning of the rangefinder, PLC intelligent control, coordinated action of the steel loading arm and furnace door interlocking, it can realize automatic, efficient and safe loading of steel billets into the furnace, thereby improving production stability and automation level.

[0012] The present invention has the following features: 1. High-precision positioning: a rangefinder is used to detect the position of the steel billet in real time, avoiding human errors and improving the accuracy of steel loading; 2. Fully automated control: PLC programming is used to realize the coordinated operation of the steel loading arm, furnace door, and conveyor roller, reducing human intervention; 3. Safety interlock: the steel loading action is deeply bound to the furnace door status, roller speed, and production system signal to prevent misoperation; 4. Energy saving and high efficiency: the intelligent opening and closing of the furnace door reduces heat loss and improves the energy efficiency of the heating furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the end-in, end-out heating furnace production mode of the present invention; Figure 2 This is a schematic diagram of the equipment layout of an embodiment of the present invention; Figure 3 This is a schematic diagram of positioning a steel billet according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the control system interface of an embodiment of the present invention; Figure 5 This is a schematic diagram of an embodiment of the present invention; In the figure: steel tapping machine 101, steel tapping roller 102, steel tapping furnace door 103, walking beam 104, furnace wall 105, steel charging furnace door 106, steel charging roller 107, steel loader 108, heating furnace 109, furnace door north side distance meter 2011, furnace door south side distance meter 2012, positioning encoder 2013, through-beam detector 2014, steel billet 2015, furnace inner wall 2016, PLC 401, host computer 1 402, host computer 2 403, motor drive device 404. DETAILED DESCRIPTION

[0014] The present invention will be further described below with reference to the accompanying drawings through embodiments.

[0015] An automatic steel-loading system for a heating furnace comprises a steel-loading machine 101, a steel-loading roller table 102, a steel-loading furnace door 103, a steel-loading furnace door 106, a steel-loading roller table 107, a steel-loading machine 108, a heating furnace 109, a rangefinder 2011 on the north side of the furnace door, a rangefinder 2012 on the south side of the furnace door, a positioning encoder 2013, a cross-beam detector 2014, a host computer and a PLC. The steel-loading furnace door 106 and the steel-loading furnace door 103 are respectively provided on the east and west sides of the heating furnace 109. The steel-loading furnace door 106 and the steel-loading furnace door 103 are respectively provided with a steel-loading roller table 107 and a steel-loading roller table 102. The steel-loading roller table 107 and the steel-loading roller table 102 are respectively provided with a steel-loading machine 108 and a steel-loading machine 101. The steel-loading roller table 107 is arranged from south to north. A furnace door south side distance meter 2012 and a furnace door north side distance meter 2011 are respectively arranged next to the steel loading roller 107 corresponding to the north and south sides of the furnace door 106, which are used to detect the length of the steel billet on the steel loading roller 107; a positioning encoder 2013 is provided on the steel loading roller 107, and a cross-beam detector 2014 is provided next to the steel loading furnace door 106, and the steel billet 2015 on the steel loading roller 107 is positioned by the positioning encoder 2013 and the cross-beam detector 2014. The steel loading roller 107 is driven by a motor drive device 404, and the furnace door north side distance meter 2011, the furnace door south side distance meter 2012, the positioning encoder 2013, the cross-beam detector 2014 and the motor drive device 404 are controlled and processed by PLC401 and the host computer.

[0016] A walking beam 104 is provided in the furnace wall 105 of the heating furnace 109 .

[0017] A method for automatically loading steel into a heating furnace uses the above system, and the specific process steps are as follows: the loading roller 107 is used to carry and transport the steel billet to be heated to the steel loading position of the end-in and end-out heating furnace; first, after the steel head of the steel billet 2015 is detected by the radiographic inspection, the positioning encoder 2013 performs a positioning on the steel billet; the positioning encoder 2013 has a disadvantage, that is, when encountering cold billets and bent billets, due to the different friction coefficients between the steel billet and the roller, some steel billets may be inaccurately positioned due to slippage; after the positioning encoder 2013 completes the positioning, if the position of the steel billet is inaccurate, a secondary positioning is performed through the rangefinder 2011 on the north side of the furnace door and the rangefinder 2012 on the south side of the furnace door: if the rangefinder on the north side of the furnace door is After 2011 detects the billet signal, the steel loading roller 107 rotates until the signal from the distance meter 2011 on the north side of the furnace door disappears, and the steel loading roller 107 stops rotating. If the distance meter 2012 on the south side of the furnace door detects the signal from the billet 2015, the steel loading roller 107 rotates until the signal from the distance meter 2012 on the south side of the furnace door disappears, and the steel loading roller 107 stops rotating to ensure that the billet 2015 is between the distance meter 2011 on the north side of the furnace door and the distance meter 2012 on the south side of the furnace door. The distance meter 2011 on the north side of the furnace door and the distance meter 2012 on the south side of the furnace door detect whether the billet position is appropriate. If the billet 2015 is positioned in the middle of the steel loading furnace door 106, the roller speed of the steel loading roller 107 is |v| < 0.1m / s and stable for 1 second; at the same time, the heating furnace sends a signal to allow steel loading. When the conditions are met, the furnace door collaborative control unit of the upper computer opens the steel loading furnace door 106, and the steel loader automatically loads steel. After the steel loading is completed, the steel loader returns to its original position, the steel loading furnace door is closed, and waits for the next steel billet; when the detected steel billet exceeds the standard length, the rangefinder 2011 on the north side of the furnace door and the rangefinder 2012 on the south side of the furnace door receive signals at the same time, and an alarm signal appears on the HMI screen of the upper computer's operating console. The steel loader will not automatically load steel to avoid causing the steel billet to scrape the furnace wall and cause a greater accident.

[0018] When the head or tail of the billet is detected by the distance meter 2011 on the north side of the furnace door and the distance meter 2012 on the south side of the furnace door, the loading roller 107 automatically runs at a low speed and adjusts the billet to be placed between the distance meter 2011 on the north side of the furnace door and the distance meter 2012 on the south side of the furnace door; after adjusting to the middle of the steel loading furnace door 106, the distance meter 2011 on the north side of the furnace door and the distance meter 2012 on the south side of the furnace door will not detect the billet signal, the roller speed of the loading roller 107 is reduced to 0 and lasts for 1s, the billet material flow and billet number are tracked in place, and after the heating furnace allows the loading signal, the loading machine automatically loads the steel.

[0019] If an alarm signal appears on the HMI screen of the upper computer console, the operator needs to manually confirm whether the length of the steel billet exceeds the standard. If it is confirmed that it exceeds the standard, the operator switches to manual loading of steel.

[0020] The positioning encoder 2013 of the present invention no longer participates in secondary positioning. No matter it is a cold billet, a hot billet or a bent billet, as long as the rangefinder 2011 on the north side of the furnace door and the rangefinder 2012 on the south side of the furnace door do not send out a steel signal, steel can be loaded effectively.

[0021] In the embodiment, the length between the distance meter 2011 on the north side of the furnace door and the distance meter 2012 on the south side of the furnace door is fixed at 11.2 m, the length of the standard steel billet is 11.1 m, and the width of the inner wall of the heating furnace is 11.29 m.

[0022] The present invention is provided with a billet length alarm function. When the billet cut by continuous casting exceeds 11.2m, the distance meter 2011 on the north side of the furnace door and the distance meter 2012 on the south side of the furnace door receive signals at the same time. Figure 3 , an alarm signal will appear on the HMI screen of the upper computer console, and the steel loader will not load steel automatically. The operator needs to confirm it manually. After the confirmation is completed, it will switch to manual loading to avoid causing the steel billet to scrape the furnace wall and cause a bigger accident.

[0023] There are multiple host computers, which in this embodiment include: a host computer 1 402 and a host computer 2 403 .

[0024] The furnace door north side distance meter 2011 and the furnace door south side distance meter 2012 detect the position of the steel billet through digital output to ensure that the steel billet is located at the center of the steel loading furnace door 106 of the heating furnace 109 and meets the furnace loading conditions.

[0025] The steel loader 108 is well-known and commonly used in the art and comprises a hydraulic system, a motor system, an automation system, and a robotic arm system. These systems push the steel into the heating furnace. The loading arm is raised by a hydraulic cylinder and driven forward by a variable frequency motor. The robotic arm pushes the steel into the furnace. Once loading is complete, the loading arm returns to its original position, the furnace door closes, and the system waits for the next steel billet.

[0026] PLC: collects field signals and completes logical actions through host computer software; The upper computer is equipped with control software, which writes control logic based on process requirements and coordinates the actions of each module. A heating furnace door collaborative control unit is provided, which communicates with the heating furnace door interlock to ensure that the furnace door automatically opens when steel is loaded and closes after steel loading is completed, reducing heat loss.

[0027] The present invention has the following features: 1. High-precision positioning: a rangefinder is used to detect the position of the steel billet in real time, avoiding human errors and improving the accuracy of steel loading; 2. Fully automated control: PLC programming is used to realize the coordinated operation of the steel loading arm, furnace door, and conveyor roller, reducing human intervention; 3. Safety interlock: the steel loading action is deeply bound to the furnace door status, roller speed, and production system signal to prevent misoperation; 4. Energy saving and high efficiency: the intelligent opening and closing of the furnace door reduces heat loss and improves the energy efficiency of the heating furnace.

Claims

1. An automatic steel loading system for a heating furnace, characterized by: The invention comprises a steel discharging machine (101), a steel discharging roller table (102), a steel discharging furnace door (103), a steel charging furnace door (106), a steel charging roller table (107), a steel charging machine (108), a heating furnace (109), a furnace door north side distance meter (2011), a furnace door south side distance meter (2012), a positioning encoder (2013), a cross-beam detection (2014), a host computer and a PLC. The steel charging furnace door (106) and the steel discharging furnace door (103) are respectively arranged on the east and west sides of the heating furnace (109). The steel charging furnace door (106) and the steel discharging furnace door (103) are respectively matched with the steel charging roller table (107) and the steel discharging roller table (102). The steel charging roller table (107) and the steel discharging roller table (102) are respectively provided with the steel charging machine (108) and the steel discharging machine (101). The steel charging roller table (107) is arranged from south to north. The steel charging furnace door (106) and the steel discharging furnace door (103) are respectively matched with the steel charging roller table (107) and the steel discharging roller table (102). 06) are provided next to the steel loading rollers (107) on the south and north sides thereof, respectively, with distance meters (212) on the south side of the furnace door and distance meters (211) on the north side of the furnace door, for detecting the length of the steel billet on the steel loading rollers (107); a positioning encoder (2013) is provided on the steel loading rollers (107), and a cross-beam detector (2014) is provided next to the steel loading furnace door (106); the steel billet (2015) on the steel loading rollers (107) is positioned by the positioning encoder (2013) and the cross-beam detector (2014); the steel loading rollers (107) are driven by a motor drive device (404); the distance meter (2011) on the north side of the furnace door, the distance meter (2012) on the south side of the furnace door, the positioning encoder (2013), the cross-beam detector (2014) and the motor drive device (404) are controlled and processed by a PLC (401) and a host computer.

2. The automatic steel loading system for a heating furnace according to claim 1, characterized in that: A walking beam (104) is provided in the furnace wall (105) of the heating furnace (109).

3. A method for automatically charging steel into a heating furnace, using the automatic steel charging system for a heating furnace according to claim 1, characterized in that The method comprises the following steps: a steel loading roller (107) is used to carry and transport the steel billet to be heated to the steel loading position of the end-in and end-out heating furnace; first, after the steel head of the steel billet (2015) is detected by the radiographic inspection, the positioning encoder (2013) positions the steel billet once; the positioning encoder (2013) has a disadvantage in that when encountering cold billets and bent billets, some billets may not be positioned accurately due to the different friction coefficients between the steel billet and the roller, resulting in slippage; after the positioning encoder (2013) is positioned, if the position of the steel billet is inaccurate, the distance meter (2011) on the north side of the furnace door and the distance meter (2012) on the south side of the furnace door are used for secondary positioning: if the distance meter (2011) on the north side of the furnace door detects the steel billet signal, the steel loading roller is used. (107) rotates until the signal of the distance meter (2011) on the north side of the furnace door disappears, and the steel loading roller (107) stops rotating; if the distance meter (2012) on the south side of the furnace door detects the signal of the billet (2015), the steel loading roller (107) rotates until the signal of the distance meter (2012) on the south side of the furnace door disappears, and the steel loading roller (107) stops rotating, ensuring that the billet (2015) is between the distance meter (2011) on the north side of the furnace door and the distance meter (2012) on the south side of the furnace door; the distance meter (2011) on the north side of the furnace door and the distance meter (2012) on the south side of the furnace door detect whether the position of the billet is appropriate, and the billet (2015) is positioned in the middle of the steel loading furnace door (106), and the roller speed of the steel loading roller (107) |v| < 0.1m / s and stable for 1 second; at the same time, the heating furnace sends a signal to allow steel loading. When the conditions are met, the furnace door cooperative control unit of the upper computer opens the steel loading furnace door (106), and the steel loader automatically loads steel. After the steel loading is completed, the steel loader returns to its original position, the steel loading furnace door closes, and waits for the next billet; when the detected billet exceeds the standard length, the distance meter on the north side of the furnace door (2011) and the distance meter on the south side of the furnace door (2012) receive signals at the same time, and an alarm signal appears on the HMI screen of the upper computer console. The steel loader will not automatically load steel to avoid causing the billet to scrape the furnace wall and cause a greater accident.

4. The method for automatically charging steel into a heating furnace according to claim 3, characterized in that: If an alarm signal appears on the HMI screen of the upper computer console, the operator needs to manually confirm whether the length of the steel billet exceeds the standard. If it is confirmed that it exceeds the standard, the operator switches to manual loading of steel.

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