CN111906150A - Steel rolling rear-end collision prevention early warning method and system - Google Patents
Steel rolling rear-end collision prevention early warning method and system Download PDFInfo
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- CN111906150A CN111906150A CN202010741492.5A CN202010741492A CN111906150A CN 111906150 A CN111906150 A CN 111906150A CN 202010741492 A CN202010741492 A CN 202010741492A CN 111906150 A CN111906150 A CN 111906150A
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- steel
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- hot metal
- metal detector
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/005—Control of time interval or spacing between workpieces
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/05—Programmable logic controllers, e.g. simulating logic interconnections of signals according to ladder diagrams or function charts
- G05B19/058—Safety, monitoring
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- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B31/00—Predictive alarm systems characterised by extrapolation or other computation using updated historic data
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- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B7/00—Signalling systems according to more than one of groups G08B3/00 - G08B6/00; Personal calling systems according to more than one of groups G08B3/00 - G08B6/00
- G08B7/06—Signalling systems according to more than one of groups G08B3/00 - G08B6/00; Personal calling systems according to more than one of groups G08B3/00 - G08B6/00 using electric transmission, e.g. involving audible and visible signalling through the use of sound and light sources
Abstract
The invention relates to the technical field of steel rolling, in particular to a steel rolling rear-end collision prevention early warning method and a steel rolling rear-end collision prevention early warning system, which comprise the following steps: firstly, inputting normal steel passing time by an upper computer picture; secondly, a hot metal detector detects that a steel signal is input to the PLC; thirdly, the PLC receives the signal and starts timing and counting; fourthly, comparing the time of the timer with the set time of the picture; fifthly, if the PLC receives the steel signal for more than or equal to 2 times within the set time of the picture, the PLC controls the intermediate relay to be closed; sixthly, alarming by an audible and visual alarm; seventhly, manually resetting the intermediate relay, and stopping alarming by the audible and visual alarm; and step eight, resetting the manual picture after the fault processing is finished, and automatically resetting the counter to start executing the detection programs from the step one to the step seven if the counting is not more than or equal to 2 times within the set time of the manual picture. The system and the method provided by the invention can prevent the rear-end collision of the billet and the false alarm.
Description
Technical Field
The invention relates to the technical field of steel rolling, in particular to a steel rolling rear-end collision prevention early warning method and system.
Background
With the development of the steel industry, the automatic control technology is more and more applied to actual production, on one hand, the production capacity of enterprises is improved by utilizing the automatic control technology, the automation degree of a production line is accelerated, and the manual labor intensity is reduced; on the other hand, the automation can effectively reduce production accidents, improve the production operation rate and the yield, and simultaneously greatly reduce the occurrence of safety accidents. In the steel rolling process, the steel tapping of the heating furnace is in a manual mode and an automatic mode, and the steel billet rear-end collision accident can be caused when the rhythm is controlled to be faster due to the fact that manual operation has errors during the manual steel tapping; in the automatic steel tapping, although the system automatically times in the interval time control, the time setting is often short, so that rear-end accidents occur, and the normal production and the yield are seriously influenced.
In the prior art, an effective control means is not available, and a method of manual monitoring or video monitoring is usually adopted for tracking, no matter manual tapping or automatic tapping is adopted, when tapping is too fast before rolling, the front and the rear blanks are contacted end to end, at the moment, the discharging roller way is stopped, and the roller way is started after the front tail enters the rolling mill; however, if the front and rear blanks are operated by mistake or are not observed to be close to each other before the rolling stand, the roller way is not stopped in time, and the front and rear blanks continuously enter the rolling mill, inevitable production accidents are easily caused
Disclosure of Invention
The invention aims to solve the technical problem of providing a steel rolling rear-end collision prevention early warning method and a steel rolling rear-end collision prevention early warning system for preventing rear-end collision of steel billets and preventing false alarms.
The invention is realized by the following technical scheme:
a steel rolling rear-end collision prevention early warning method is characterized by comprising the following steps:
firstly, inputting normal steel passing rhythm playing time by an upper computer picture;
secondly, when a hot metal detector arranged in front of the side of the steel tapping hole of the heating furnace detects a steel signal, inputting a signal (10.0) to a PLC input point;
thirdly, the PLC receives the signal to start timing and count simultaneously;
fourthly, comparing the time of the timer with the set time of the picture;
fifthly, if the PLC receives a steel signal sent by the hot metal detector for more than or equal to 2 times within the set time of the picture, the PLC outputs a (Q0.0) command, and the coil of the intermediate relay is electrified;
sixthly, closing a normally open point of the intermediate relay, electrifying the audible and visual alarm and starting audible and visual alarm;
seventhly, manually resetting the intermediate relay, and stopping alarming by the audible and visual alarm;
and step eight, resetting the manual picture after the fault processing is finished, and automatically resetting the counter to start executing the detection programs from the step one to the step seven if the counting is not more than or equal to 2 times within the set time of the manual picture.
Further, the hot metal detector detects that a steel signal exists, the signal (10.0) is input to the PLC, the PLC receives the signal and carries out filtering judgment, if the duration time of the signal is longer than the set time, it is determined that a red billet is discharged from the furnace, otherwise, the signal is filtered as an error signal.
Optimally, the set signal duration is 1 second.
The steel rolling rear-end collision prevention early warning system comprises a hot metal detector, a PLC (programmable logic controller) module, an intermediate relay, an audible and visual alarm and a fixed support, wherein the fixed support is fixedly installed in front of the steel tapping hole side of a heating furnace, the hot metal detector is fixedly installed on the fixed support, the height of the hot metal detector is consistent with the axis of a red blank on a steel tapping roller way, the signal output end of the hot metal detector is connected with the input end of the PLC module through a cable, the output end of the PLC module is connected with the audible and visual alarm through the cable, the intermediate relay is installed between the PLC module and the audible and visual alarm.
Further, a heat insulation baffle is fixedly mounted in front of the hot metal detector, and a detection through hole is formed in the position, right opposite to the hot metal detector, of the heat insulation baffle.
Advantageous effects of the invention
The steel rolling rear-end collision prevention early warning method and system protected by the invention have the following advantages:
1. the automatic system is adopted to realize full-automatic control, thereby effectively avoiding the occurrence of rear-end collision accidents of the steel billets caused by human or system errors.
2. After each fault processing is finished, false-detection prevention is carried out before tapping after the manual picture is reset, if the counting is not more than or equal to 2 times within the set time of the manual picture, the counter is automatically reset to start an automatic detection program, false alarm caused by the fact that the flame is burned in the furnace and exits from the furnace door is effectively avoided, and the automatic early warning system is more accurate and reliable.
3. And the transmission of the thermal detection signal is adopted, and an automatic filtering program is added, so that false alarm or no alarm caused by error signals is further effectively avoided.
4. Simple structure need not artifical the supervision, reduces artifical intensity of labour.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic diagram of a control system;
in the figure: 1. the hot metal detector comprises a hot metal detector, a PLC module, an intermediate relay, an audible and visual alarm, a fixing support, a heat insulation baffle 6, a steel tapping hole 7, a heating furnace 8 and a detection through hole 9.
Detailed Description
A steel rolling rear-end collision prevention early warning method is characterized by comprising the following steps:
firstly, inputting normal steel passing rhythm playing time by an upper computer picture; typically this time is around 10 minutes.
Secondly, when a hot metal detector arranged in front of the side of the steel tapping hole of the heating furnace detects a steel signal, inputting a signal (10.0) to a PLC input point;
thirdly, the PLC receives the signal to start timing and count simultaneously;
fourthly, comparing the time of the timer with the set time of the picture;
fifthly, if the PLC receives a steel signal sent by the hot metal detector for more than or equal to 2 times within the set time of the picture, the PLC outputs a (Q0.0) command, and the coil of the intermediate relay is electrified;
sixthly, closing a normally open point of the intermediate relay, electrifying the audible and visual alarm and starting audible and visual alarm;
seventhly, manually resetting the intermediate relay, and stopping alarming by the audible and visual alarm;
and step eight, resetting the manual picture after the fault processing is finished, and automatically resetting the counter to start executing the detection programs from the step one to the step seven if the counting is not more than or equal to 2 times within the set time of the manual picture.
Further, the hot metal detector detects that a steel signal exists, the signal (10.0) is input to the PLC, the PLC receives the signal and carries out filtering judgment, if the duration time of the signal is longer than the set time, a red billet is considered to be discharged from the furnace, otherwise, the red billet is filtered out as a false signal, the false signal is effectively filtered, the detection accuracy is improved, and false alarm is prevented.
Optimally, the set signal duration is 1 second.
The utility model provides a steel rolling early warning system that knocks into back, its includes hot metal detector 1, PLC module 2, auxiliary relay 3, audible-visual annunciator 4 and fixed bolster 5, fixed bolster fixed mounting is in 7 side the place ahead of tapping hole in heating furnace 8, hot metal detector is adorned on the fixed bolster admittedly, and its height is unanimous with the red base axis on the tapping roll table, and the signal output part of hot metal detector passes through the cable with the input of PLC module and is connected, and the output of PLC module passes through the cable and is connected with audible-visual annunciator, and installs auxiliary relay between the two, auxiliary relay is normally open relay.
Further, a heat insulation baffle 6 is fixedly installed in front of the hot metal detector, and a detection through hole 9 is formed in the position, right opposite to the hot metal detector, of the heat insulation baffle. Due to the arrangement of the heat insulation baffle, the influence of the flame burnt in the furnace on the detection signal of the hot metal detector can be effectively prevented, and the input of non-red blank signals is prevented.
The intermediate relay is 21KA 1.
According to the early warning method and system for preventing steel rolling rear-end collision, when a hot metal detector detects a steel signal, the signal is output to a PLC (programmable logic controller), if the PLC receives the steel signal for more than or equal to 2 times within a set time, the time interval between the front steel billet and the rear steel billet is short, rear-end collision can occur, the PLC controls an intermediate relay to be closed, a sound-light alarm is powered on, sound-light alarm starts, generally, the time interval between the front steel billet and the rear steel billet is about 10 minutes, an operator receives the alarm signal and timely finishes processing, and the occurrence of the rear-end collision accident of the steel billets is prevented. The system and the method realize full-automatic control, effectively put an end to human or system errors and effectively prevent the occurrence of rear-end collision accidents of the steel billets; after each fault processing is finished, false-detection prevention is carried out before tapping after the manual picture is reset, if the counting is not more than or equal to 2 times within the set time of the manual picture, the counter is automatically reset to start an automatic detection program, false alarm caused by the fact that the flame is burned in the furnace and exits from the furnace door is effectively avoided, and the automatic early warning system is more accurate and reliable; meanwhile, due to the fact that thermal detection signal transmission is adopted and automatic filtering is conducted, false alarm or no alarm caused by error signals is effectively avoided, the system works accurately and reliably, the whole system is simple in structure, manual monitoring is not needed, and manual labor intensity is reduced.
In conclusion, the steel rolling rear-end collision prevention early warning method and system protected by the invention can prevent the steel billet from rear-end collision and false alarm.
Various modifications and alterations to this invention will become apparent to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. A steel rolling rear-end collision prevention early warning method is characterized by comprising the following steps:
firstly, inputting normal steel passing rhythm playing time by an upper computer picture;
secondly, when a hot metal detector arranged in front of the side of the steel tapping hole of the heating furnace detects a steel signal, inputting a signal (10.0) to a PLC input point;
thirdly, the PLC receives the signal to start timing and count simultaneously;
fourthly, comparing the time of the timer with the set time of the picture;
fifthly, if the PLC receives a steel signal sent by the hot metal detector for more than or equal to 2 times within the set time of the picture, the PLC outputs a (Q0.0) command, and the coil of the intermediate relay is electrified;
sixthly, closing a normally open point of the intermediate relay, electrifying the audible and visual alarm and starting audible and visual alarm;
seventhly, manually resetting the intermediate relay, and stopping alarming by the audible and visual alarm;
and step eight, resetting the manual picture after the fault processing is finished, and automatically resetting the counter to start executing the detection programs from the step one to the step seven if the counting is not more than or equal to 2 times within the set time of the manual picture.
2. The steel rolling rear-end collision prevention early warning method according to claim 1, characterized in that the hot metal detector detects a steel signal, the signal (10.0) is input to the PLC, the PLC receives the signal and performs filtering judgment, if the duration of the signal is longer than a set time, it is determined that a red billet is discharged from the furnace, otherwise, the red billet is filtered as a false signal.
3. The early warning method for preventing rear-end collision of rolled steel as claimed in claim 2, wherein the set signal duration is 1 second.
4. The steel rolling rear-end collision prevention early warning system is characterized by comprising a hot metal detector, a PLC (programmable logic controller) module, an intermediate relay, an audible and visual alarm and a fixed support, wherein the fixed support is fixedly installed in front of the steel tapping hole side of a heating furnace, the hot metal detector is fixedly installed on the fixed support, the height of the hot metal detector is consistent with the axis of a red blank on a steel tapping roller way, the signal output end of the hot metal detector is connected with the input end of the PLC module through a cable, the output end of the PLC module is connected with the audible and visual alarm through a cable, the intermediate relay is installed between the PLC module and the audible and visual alarm.
5. The steel rolling rear-end collision prevention early warning system according to claim 4, wherein a heat insulation baffle is fixedly installed in front of the hot metal detector, and a detection through hole is formed in the position, opposite to the hot metal detector, of the heat insulation baffle.
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| CN202010741492.5A CN111906150A (en) | 2020-07-29 | 2020-07-29 | Steel rolling rear-end collision prevention early warning method and system |
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| CN202010741492.5A CN111906150A (en) | 2020-07-29 | 2020-07-29 | Steel rolling rear-end collision prevention early warning method and system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114762866A (en) * | 2022-05-30 | 2022-07-19 | 宝武集团鄂城钢铁有限公司 | Method for controlling rolling rhythm of on-line quenching steel plate for rolling medium plate single stand |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114762866A (en) * | 2022-05-30 | 2022-07-19 | 宝武集团鄂城钢铁有限公司 | Method for controlling rolling rhythm of on-line quenching steel plate for rolling medium plate single stand |
| CN114762866B (en) * | 2022-05-30 | 2023-09-19 | 宝武集团鄂城钢铁有限公司 | Method for controlling rolling rhythm of on-line quenched steel plate rolled by medium plate single stand |
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Application publication date: 20201110 |