CN112725839A - Visual measurement crust breaking system method and device for aluminum electrolysis multifunctional unit - Google Patents
Visual measurement crust breaking system method and device for aluminum electrolysis multifunctional unit Download PDFInfo
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- CN112725839A CN112725839A CN202110180187.8A CN202110180187A CN112725839A CN 112725839 A CN112725839 A CN 112725839A CN 202110180187 A CN202110180187 A CN 202110180187A CN 112725839 A CN112725839 A CN 112725839A
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- crust breaking
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- aluminum electrolysis
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- 230000000007 visual effect Effects 0.000 title claims abstract description 41
- 238000005259 measurement Methods 0.000 title claims abstract description 26
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 21
- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 21
- 238000005868 electrolysis reaction Methods 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title claims abstract description 19
- 230000007246 mechanism Effects 0.000 claims abstract description 41
- 239000010720 hydraulic oil Substances 0.000 claims abstract description 3
- 238000012544 monitoring process Methods 0.000 claims abstract description 3
- 239000003921 oil Substances 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 abstract description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 230000006698 induction Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical group O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 230000011664 signaling Effects 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
- C25C3/14—Devices for feeding or crust breaking
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
- C25C3/20—Automatic control or regulation of cells
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electrolytic Production Of Metals (AREA)
Abstract
The invention discloses a visual measurement crust breaking system method and device for an aluminum electrolysis multifunctional unit, wherein the method adopts a crust breaking system device, a visual sensor is utilized to carry out spatial positioning measurement at different positions, then a control device calculates the moving path of crust breaking operation according to spatial position information fed back by the visual sensor, the positions of all components are corrected, the movement of all mechanisms is controlled, and the start of a crust breaking machine head to start crust breaking or the end of crust breaking is judged by monitoring the pressure in a hydraulic oil cylinder. The visual measurement crust breaking system method and the device for the aluminum electrolysis multifunctional unit automatically position and complete the whole crust breaking work by visual measurement, can improve the pole changing efficiency, reduce the working time of workers, lighten the labor intensity and improve the production operation safety.
Description
Technical Field
The invention belongs to the technical field of aluminum electrolysis, and particularly relates to a visual measurement crust breaking system method and device for an aluminum electrolysis multifunctional unit.
Background
The production of industrial primary aluminum mainly adopts a molten salt electrolysis method, hundreds of electrolytic cells are connected in series, and the decomposition of aluminum oxide is realized under the action of strong direct current. The anode needs to be replaced regularly under the current process technical conditions. The shell surface of the anode covering material needs to be smashed when the anode is replaced in the aluminum electrolysis multifunctional unit, so that the anode scrap can be taken out conveniently.
In the prior art, the invention patent with the publication number of CN104532298A discloses an electrolytic bath crust breaking system and a method, the system comprises a cylinder, a cylinder hammer head, an actuating mechanism and a control device, wherein the cylinder hammer head is provided with a position reflector, a position sensor corresponding to the position reflector is arranged on the wall of the cylinder or the electrolytic bath, and if the position reflector on the cylinder hammer head and the position sensor on the wall of the cylinder or the electrolytic bath generate induction, the control device controls the cylinder to reverse and stop crust breaking; if the position reactor on the hammer head of the air cylinder does not generate induction with the position sensor on the wall of the air cylinder or the electrolytic bath within the preset time period, the control device controls the air cylinder to reverse and crust again. The device and the method can achieve the effects of controlling the stroke of the cylinder and reducing the soaking time of the hammer head in electrolyte.
In addition, the invention patent with the publication number of CN107904625A discloses an intelligent crust breaking system, which comprises a control cabinet, a combination valve, a signaling adjusting device, a crust breaking cylinder and a crust breaking hammer head; the combination valve comprises a reversing valve, a pressure adjusting knob and a valve body, wherein the reversing valve and the pressure valve extend out of the top of the valve body, and the pressure adjusting knob extends out of one side of the valve body; the signal sending adjusting device is arranged on one side of the valve body, the valve body is arranged on a rear end cover of the crust breaking cylinder, and the crust breaking hammer head is hinged with a piston rod of the crust breaking cylinder through a fork rod joint; the combination valve is connected with the control cabinet through a line.
Although some technical innovations are carried out on the aluminum electrolysis intelligent crust breaking system in the prior art, the problems of reducing labor intensity and improving production operation safety by combining measurement positioning and crust breaking work are not considered yet.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a visual measurement crust breaking system method and device for an aluminum electrolysis multifunctional unit.
The invention is realized by the following steps:
a visual measurement crust breaking system method for an aluminum electrolysis multifunctional unit adopts a crust breaking system device, a visual sensor is utilized to carry out spatial positioning measurement at different positions, then a control device calculates the moving path of crust breaking operation according to spatial position information fed back by the visual sensor, the positions of all components are corrected, all mechanisms are controlled to move, and the start of a crust breaking machine head to start crust breaking or the end of crust breaking is judged by monitoring the pressure in a hydraulic oil cylinder. The control device comprises host computer, server, PLC controller etc. and main function is: path planning, data processing, issuing instructions, etc.
Specifically, the method comprises the following steps:
s1, after the unit receives an instruction of replacing a certain anode, the control device controls the cart device and the cart device of the unit to run above the electrolytic bath and is positioned above the specified anode scrap;
s2, rotating the tool rotating mechanism to drive the vision lifting mechanism and the vision sensor to be above the guide rod of the residual anode; the tool rotating mechanism is used for installing various operating tools in a rotatable rotating support, is provided with a driving device in a rotating way, and can rotate a specified tool to a specific station to perform operation through the tool rotating mechanism;
s3, the vision lifting mechanism drives the vision sensor to move up and down to realize the space positioning measurement at different positions; the visual lifting device is a motor lead screw linear motion unit and can realize rapid and accurate linear motion;
s4, calculating the moving path of the crust breaking operation by the control device according to the space position information fed back by the visual sensor, correcting the positions of the large unit vehicle device, the small unit vehicle device and the tool swing mechanism, and guiding the servo hydraulic cylinder to drive the moving frame and the crust breaking machine head to move downwards;
s5, after the device is in place, the hydraulic cylinder with the pressure sensor extends out, and when the pressure in the hydraulic cylinder is monitored to rise, the crust breaking machine head is started to start crust breaking;
s6, when the pressure in the oil cylinder is monitored to be suddenly released, judging that the crust breaking is finished at the point, and withdrawing the hydraulic cylinder with the pressure sensor;
and S7, performing crust breaking operation of the next point according to the moving operation path until all crust breaking operations are finished.
A visual measurement crust breaking system device of an aluminum electrolysis multifunctional unit for the method comprises a unit cart device, wherein the unit cart device runs on a factory building track of an aluminum electrolysis workshop, two main beams are arranged on the unit cart device, a trolley track is arranged on the two main beams, a unit trolley device is arranged on the trolley track, and the unit trolley device runs along the trolley track; a tool swing mechanism and a control device are arranged on the unit trolley device; the tool swing mechanism is provided with a visual lifting mechanism and a fixed guide frame, the visual lifting mechanism is provided with a visual sensor, and the visual lifting mechanism can drive the visual sensor to lift up and down to realize measurement tasks at different positions.
The large unit vehicle device, the small unit vehicle device and the tool slewing mechanism are provided with respective automatic accurate positioning systems. The system consists of an encoder, a reading head, an encoding ruler and the like. The encoder and the code reading head are installed on the running mechanism, the code ruler is installed on a moving track line of the running mechanism, and when the running mechanism moves, the code reading head can read corresponding position coordinate information on the code ruler, so that the current real-time position of the running mechanism is obtained.
NewThe hydraulic device further comprises a servo hydraulic cylinder and a hydraulic cylinder with a pressure sensor, wherein the servo hydraulic cylinder is arranged on the fixed guide frame and can drive the movable frame and the crust breaking machine head to move up and down; one end of the hydraulic cylinder with the pressure sensor is arranged on the movable frame, and the striking position of the crust breaking machine head can be adjusted.
Compared with the prior art, the visual measurement crust breaking system method and the device for the multifunctional aluminum electrolysis unit automatically position and complete the whole crust breaking work by means of visual measurement, can improve the pole changing efficiency, reduce the working time of workers, lighten the labor intensity and improve the production operation safety.
Drawings
Fig. 1 is a schematic structural view of the present invention.
The labels in the figures are: 1-a unit cart device, 2-a unit trolley device, 3-a tool swing mechanism, 4-a control device, 5-a vision lifting mechanism, 6-a vision sensor, 7-a fixed guide frame, 8-a moving frame, 9-a servo hydraulic cylinder, 10-a hydraulic cylinder with a pressure sensor, 11-a crust breaking machine head, 12-an electrolytic tank and 13-a residual anode.
Detailed Description
The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.
As shown in fig. 1, the present invention is implemented as follows: the large unit vehicle device 1 runs on a rail of a workshop of an aluminum electrolysis workshop, the small unit vehicle device 2 runs on rails on two main beams of the large unit vehicle device 1, the tool swing mechanism 3 is installed on the small unit vehicle device 2, and the large unit vehicle device 1, the small unit vehicle device 2 and the tool swing mechanism 3 are provided with respective automatic accurate positioning systems; the control device 4 is arranged on the unit trolley device 2; the visual lifting mechanism 5 and the fixed guide frame 7 are arranged on the tool swing mechanism 3, the visual sensor 6 is arranged on the visual lifting mechanism 5, and the visual lifting mechanism 5 can drive the visual sensor 6 to lift up and down to realize measurement tasks at different positions; the servo hydraulic cylinder 9 is arranged on the fixed guide frame 7 and can drive the movable frame 8 and the crust breaking machine head 11 to move up and down; one end of a hydraulic cylinder 10 with a pressure sensor is arranged on the movable frame 8, and the striking position of the crust breaker head 11 can be adjusted. The whole system is controlled by the control device 4. The fixed guide frame 7 consists of profile steel, a guide groove and the like; the movable frame 8 is formed by welding a steel plate, section steel, or the like, and the movable frame 8 can slide up and down in the guide groove of the fixed guide frame 7.
After the unit receives an instruction of replacing a certain anode, the control device 4 controls the unit cart device 1 and the unit trolley device 2 to run above the electrolytic bath 12 and to be positioned above the specified anode scrap 13. The tool rotating mechanism 3 rotates to drive the vision lifting mechanism 5 and the vision sensor 6 to be above the guide rod of the anode scrap 13, and the vision lifting mechanism 5 drives the vision sensor 6 to move up and down to realize space positioning measurement at different positions. According to the space position information fed back by the vision sensor 6, the control device 4 calculates the moving path of the crust breaking operation, the positions of the large unit vehicle device 1, the small unit vehicle device 2 and the tool swing mechanism 3 are corrected, the servo hydraulic cylinder 9 is guided to drive the moving frame 8 and the crust breaking machine head 11 to move downwards, after the positions are in place, the hydraulic cylinder 10 with the pressure sensor extends out, and when the pressure in the hydraulic cylinder is monitored to rise, the crust breaking machine head 11 is started to start crust breaking. When the pressure in the oil cylinder is monitored to be suddenly relieved, the crust breaking at the point is judged to be finished, and the hydraulic cylinder 10 with the pressure sensor is withdrawn. And then, carrying out crust breaking operation of the next point according to the moving operation path until all crust breaking operations are finished.
Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.
Claims (5)
1. A visual measurement crust breaking system method for an aluminum electrolysis multifunctional unit is characterized in that: the method adopts a crust breaking system device, a visual sensor (6) is utilized to carry out space positioning measurement at different positions, then a control device (4) calculates the moving path of crust breaking operation according to space position information fed back by the visual sensor (6), corrects the positions of all parts, controls all mechanisms to move, and judges whether a crust breaking machine head (11) is started to crust or crust breaking is finished by monitoring the pressure in a hydraulic oil cylinder.
2. A multifunctional machine set vision measurement crust breaking system method according to claim 1, characterized in that the method comprises the following steps:
s1, after the unit receives an instruction of replacing a certain anode, the control device (4) controls the large trolley device (1) and the small trolley device (2) of the unit to run above the electrolytic bath (12) and is positioned above the specified anode scrap (13);
s2, rotating the tool rotating mechanism (3) to drive the visual lifting mechanism (5) and the visual sensor (6) to be above the guide rod of the anode scrap (13);
s3, the vision lifting device (5) drives the vision sensor (6) to move up and down to realize the space positioning measurement at different positions;
s4, calculating the moving path of the crust breaking operation by the control device (4) according to the space position information fed back by the visual sensor (6), correcting the positions of the large unit vehicle device (1), the small unit vehicle device (2) and the tool swing mechanism (3), and guiding the servo hydraulic cylinder (9) to drive the moving frame (8) and the crust breaking machine head (11) to move downwards;
s5, after the device is in place, the hydraulic cylinder (10) with the pressure sensor extends out, and when the pressure in the oil cylinder is monitored to rise, the crust breaking machine head (11) is started to start crust breaking;
s6, when the pressure in the oil cylinder is monitored to be suddenly released, the crust breaking at the point is judged to be finished, and the hydraulic cylinder (10) with the pressure sensor is retracted;
and S7, performing crust breaking operation of the next point according to the moving operation path until all crust breaking operations are finished.
3. An aluminum electrolysis multifunctional unit visual measurement crust breaking system device for realizing the method of claim 1 or 2, which is characterized in that: the aluminum electrolysis workshop building comprises a unit cart device (1), wherein the unit cart device (1) runs on a workshop track of an aluminum electrolysis workshop, two main beams are arranged on the unit cart device (1), trolley tracks are arranged on the two main beams, a unit trolley device (2) is arranged on the trolley tracks, and the unit trolley device (2) runs along the trolley tracks; a tool swing mechanism (3) is arranged on the unit trolley device (2), and a control device (4) is also arranged on the unit trolley device (2); the tool rotating mechanism (3) is provided with a visual lifting mechanism (5) and a fixed guide frame (7), the visual lifting mechanism (5) is provided with a visual sensor (6), and the visual lifting mechanism (5) can drive the visual sensor (6) to lift up and down to realize measurement tasks at different positions.
4. The visual measurement crust breaking system device of the aluminum electrolysis multifunctional unit as claimed in claim 3, wherein: the large unit trolley device (1), the small unit trolley device (2) and the tool swing mechanism (3) are respectively provided with an automatic accurate positioning system.
5. The visual measurement crust breaking system device of the aluminum electrolysis multifunctional unit as claimed in claim 3, wherein: the hydraulic control device is characterized by further comprising a servo hydraulic cylinder (9) and a hydraulic cylinder (10) with a pressure sensor, wherein the servo hydraulic cylinder (9) is mounted on the fixed guide frame (7) and can drive the movable frame (8) and the crust breaking machine head (11) to move up and down; one end of the hydraulic cylinder (10) with the pressure sensor is arranged on the movable frame (8), and the striking position of the crust breaking machine head (11) can be adjusted.
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113403647A (en) * | 2021-06-08 | 2021-09-17 | 湖南天桥嘉成智能科技有限公司 | Method for removing massive aluminum electrolysis slag and slag crushing device of aluminum electrolysis multifunctional unit |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111485254A (en) * | 2020-05-26 | 2020-08-04 | 贵阳铝镁设计研究院有限公司 | Intelligent twisting and pulling device and method for aluminum electrolysis multifunctional unit |
CN111503468A (en) * | 2020-05-26 | 2020-08-07 | 贵阳铝镁设计研究院有限公司 | Intelligent aluminum electrolysis multifunctional unit visual positioning device and method thereof |
CN111575741A (en) * | 2020-05-26 | 2020-08-25 | 贵阳铝镁设计研究院有限公司 | Intelligent crust breaking device and method for aluminum electrolysis multifunctional unit |
CN215628350U (en) * | 2021-02-08 | 2022-01-25 | 贵阳铝镁设计研究院有限公司 | Visual measurement crust breaking system device for aluminum electrolysis multifunctional unit |
-
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- 2021-02-08 CN CN202110180187.8A patent/CN112725839A/en active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111485254A (en) * | 2020-05-26 | 2020-08-04 | 贵阳铝镁设计研究院有限公司 | Intelligent twisting and pulling device and method for aluminum electrolysis multifunctional unit |
CN111503468A (en) * | 2020-05-26 | 2020-08-07 | 贵阳铝镁设计研究院有限公司 | Intelligent aluminum electrolysis multifunctional unit visual positioning device and method thereof |
CN111575741A (en) * | 2020-05-26 | 2020-08-25 | 贵阳铝镁设计研究院有限公司 | Intelligent crust breaking device and method for aluminum electrolysis multifunctional unit |
CN215628350U (en) * | 2021-02-08 | 2022-01-25 | 贵阳铝镁设计研究院有限公司 | Visual measurement crust breaking system device for aluminum electrolysis multifunctional unit |
Non-Patent Citations (2)
Title |
---|
张世军;: "新型通用型铝电解多功能机组的设计研发", 有色矿冶, no. 06, pages 54 - 56 * |
楚文江;高军永;柴婉秋;马靓;吴中鼎;: "铝电解多功能机组智能定位控制系统设计与实践", 有色设备, no. 02, pages 15 - 18 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113403647A (en) * | 2021-06-08 | 2021-09-17 | 湖南天桥嘉成智能科技有限公司 | Method for removing massive aluminum electrolysis slag and slag crushing device of aluminum electrolysis multifunctional unit |
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Application publication date: 20210430 |