阅读说明：本技术 采用激光测速传感器进行板柸长度测量的方法和系统 (Method and system for measuring length of blank by using laser speed measuring sensor ) 是由 张静 于 2019-09-27 设计创作，主要内容包括：本发明提供了一种采用激光测速传感器进行板柸跟踪测量的方法和系统,在切割辊道前后分别增设一个激光测速传感器,记为前激光测速传感器和后激光测速传感器,当切割辊道的中间存在板柸时,开始启动激光测速传感器进行测速；控制单元识别后激光测速传感器的有效信号,根据有效信号对速度值进行积分计算,得到移动距离值,控制单元识别激光测速传感器的无效信号,使用辅助编码器根据无效信号计算移动距离值。能够解决测长辊打滑产生误差的问题,且根据精度跟踪信息反推是否存在打滑问题；对异常位置的跟踪更加准确,能够减少废柸的长度损失,使得取消测长辊,降低机械设备的维护费用,提高跟踪精度后,使得铸造长信息更准确,板柸长信息也更准确。(The invention provides a method and a system for performing slab tracking measurement by using a laser speed measuring sensor, wherein the method comprises the steps of respectively adding a laser speed measuring sensor before and after a roller way is cut, marking as a front laser speed measuring sensor and a rear laser speed measuring sensor, and starting the laser speed measuring sensor to measure speed when a slab exists in the middle of the roller way; the control unit identifies effective signals of the laser speed measuring sensor, integral calculation is carried out on speed values according to the effective signals to obtain a moving distance value, the control unit identifies invalid signals of the laser speed measuring sensor, and an auxiliary encoder is used for calculating the moving distance value according to the invalid signals. The problem of error caused by the slipping of the length measuring roller can be solved, and whether the slipping problem exists is reversely deduced according to the precision tracking information; the tracking of the abnormal position is more accurate, the length loss of the blank can be reduced, a length measuring roller is omitted, the maintenance cost of mechanical equipment is reduced, and after the tracking precision is improved, the cast length information is more accurate, and the blank information is also more accurate.)

1. A method for performing blank tracking measurement by using a laser speed measuring sensor is characterized by comprising the following steps:

laser speed measurement: respectively adding a laser speed measuring sensor in front of and behind the cutting roller way, recording as a front laser speed measuring sensor and a rear laser speed measuring sensor, and starting the laser speed measuring sensors to measure speed when a blank exists in the middle of the cutting roller way;

a distance measuring and calculating step: the control unit identifies effective signals of the laser speed measuring sensor, integral calculation is carried out on speed values according to the effective signals to obtain a moving distance value, the control unit identifies invalid signals of the laser speed measuring sensor, and an auxiliary encoder is used for calculating the moving distance value according to the invalid signals.

2. The method for performing slab tracking measurement by using the laser speed measuring sensor as claimed in claim 1, further comprising the following step of: respectively installing hot metal detectors which are recorded as a left hot metal detector and a right hot metal detector on two sides of the cutting roller way, measuring a detection distance between the left hot metal detector and the right hot metal detector, wherein the detection distance can correct the casting length, after pouring is started, moving a cast blank through the cutting roller way, and correcting the casting length according to the actual metallurgical length if a control unit receives a signal of the left hot metal detector, wherein the metallurgical length is the length from the liquid level of a crystallizer of the continuous casting machine to the tail end of the cast blank; and if the control unit receives the signal of the right hot metal detector, correcting the casting length according to the detection distance.

3. The method for performing slab tracking measurement by using a laser speed measuring sensor as claimed in claim 2, wherein the moving distance value is calculated according to the following formula:

wherein s represents a movement distance value;

c represents the propagation speed of light in the atmosphere;

dt represents the differentiation over time t;

t₀the time required for the light to travel back and forth to two measurement points once.

4. The method for performing slab tracking measurement by using a laser tachometric sensor as claimed in claim 1, wherein the length of the slab is calculated by the following formula:

L＝S-A(t)-B(t)cosβ

wherein L represents a slab length;

s represents the distance between the rear laser speed measuring sensor and the fixed standard plate;

beta represents the included angle between the rear laser speed measuring sensor and the horizontal plane;

a (t) represents the distance between the front laser speed measuring sensor and the fixed standard plate;

and B (t) represents the distance between the rear laser tacho sensor and the sheet blank head.

5. A system for performing blank tracking measurement by using a laser speed measuring sensor is characterized by comprising the following steps:

the laser speed measuring module: respectively adding a laser speed measuring sensor in front of and behind the cutting roller way, recording as a front laser speed measuring sensor and a rear laser speed measuring sensor, and starting the laser speed measuring sensors to measure speed when a blank exists in the middle of the cutting roller way;

the distance measuring and calculating module comprises: the control unit identifies effective signals of the laser speed measuring sensor, integral calculation is carried out on speed values according to the effective signals to obtain a moving distance value, the control unit identifies invalid signals of the laser speed measuring sensor, and an auxiliary encoder is used for calculating the moving distance value according to the invalid signals.

6. The system for performing slab tracking measurement by using a laser speed measuring sensor as claimed in claim 5, further comprising a tracking measurement module: respectively installing hot metal detectors which are recorded as a left hot metal detector and a right hot metal detector on two sides of the cutting roller way, measuring a detection distance between the left hot metal detector and the right hot metal detector, wherein the detection distance can correct the casting length, after pouring is started, moving a cast blank through the cutting roller way, and correcting the casting length according to the actual metallurgical length if a control unit receives a signal of the left hot metal detector, wherein the metallurgical length is the length from the liquid level of a crystallizer of the continuous casting machine to the tail end of the cast blank; and if the control unit receives the signal of the right hot metal detector, correcting the casting length according to the detection distance.

7. The system for performing slab tracking measurement by using a laser speed measuring sensor as claimed in claim 6, wherein the moving distance value is calculated according to the following formula:

wherein s represents a movement distance value;

c represents the propagation speed of light in the atmosphere;

dt represents the differentiation over time t;

t₀the time required for the light to travel back and forth to two measurement points once.

8. The system for performing slab tracking measurement using a laser tachometric sensor as in claim 6, wherein the length of the slab is calculated by:

L＝S-A(t)-B(t)cosβ

wherein L represents a slab length;

s represents the distance between the rear laser speed measuring sensor and the fixed standard plate;

beta represents the included angle between the rear laser speed measuring sensor and the horizontal plane;

a (t) represents the distance between the front laser speed measuring sensor and the fixed standard plate;

and B (t) represents the distance between the rear laser tacho sensor and the sheet blank head.

9. The method for performing slab tracking measurement by using a laser tachometer sensor as claimed in claim 3 or the system for performing slab tracking measurement by using a laser tachometer sensor as claimed in claim 7, wherein the method for performing slab tracking measurement by using a laser tachometer sensor is characterized in that

10. The method for performing slab tracking measurement by using a laser tachometer sensor as claimed in claim 3 or the system for performing slab tracking measurement by using a laser tachometer sensor as claimed in claim 7, wherein the method for performing slab tracking measurement by using a laser tachometer sensor is characterized in that

Technical Field

The invention relates to the technical field of slab length measurement, in particular to a method and a system for measuring the slab length by using a laser speed measuring sensor, and particularly relates to a method for measuring the continuous casting blank length by using the laser speed measuring sensor as a base.

Background

The position information of the head portion of the dummy bar, the tail portion of the dummy bar, the head portion of the plate and the tail portion of the plate, the length information of the casting length, the plate length and the like are important data in the operation process of the continuous casting machine. Such location information and length information may be collectively referred to as slab tracking information for a continuous caster. Most of the conventional continuous casting machines use sector pinch roll encoder signals and cutter length measuring roll signals, and the sheet tracking information is obtained after mechanical parameter calculation. And tracking the head position of the blank by using an infrared sizing technology through the individual continuous casting machine, and sending a blank cutting starting instruction according to a preset value of the length of the blank.

The sheet quality management model collects life cycle data of the sheet based on the cast long segment, meaning that the cast long or sheet length is a basis upon which the sheet quality data can be tracked. Encoder signals using pinch rolls and length measuring rolls are in a mechanical contact type measuring mode, and roller and plate slip (static friction), roller abrasion, mechanical error accumulation and the like cause inconsistency between the cast length or plate length calculated by a control system and an actual plate length. Such a variance is within a substantially acceptable margin with respect to a sheet and generally does not affect the cutting operation of the sheet. However, after long-time pouring, obvious accumulated errors are generated, the accumulated errors are larger than the length of the sheet determined length, and obstacles are caused to quality dissimilarity analysis, quality problem tracing, quality model combination of the previous and subsequent processes and the like, so that improvement is urgently needed.

The use of infrared sizing has problems such as no slippage, no mechanical wear, etc., but has problems such as nonlinearity, relatively poor stability, large system detection error, limitation of mounting position, etc., but also has a problem of cumulative error.

If the length is measured by using a laser length measuring method, the problem of large error caused by angular deviation due to roller table vibration and the problem of signal loss caused by diffuse reflection due to unsmooth sheet surface exist.

Patent document 103341608A discloses a continuous casting blank scale detecting and cutting device, an encoder-based scale detecting device, mainly including a withdrawal and straightening machine having a driving roller and a driven roller, a cutting unit, and a pulse encoder. It is characterized in that: and connecting a pulse encoder with a withdrawal straightening machine having a driving roller and a driven roller, wherein the withdrawal straightening machine rotates along with the movement of the cast blank, and the pulse encoder calculates the length of the cast blank according to the rotation of the withdrawal straightening machine. However, the pulse encoder is connected to the withdrawal roll and the length of the blank is calculated based on the rotation of the withdrawal roll, and there is a disadvantage in that the accuracy of sizing is reduced and the maintenance cost is increased due to the wear of the roll caused by the long time contact of the withdrawal roll with the sheet having a high temperature.

Patent document 203343397U discloses a sizing system of a continuous caster cutting machine, which is a measurement and control system using a sizing camera as a sensor and an image processing technology as a core. An infrared camera is installed at a fixed location in the field, and the sheet information is extracted from the image when the sheet enters the photographing range. According to the patent, a certain error exists when a sheet is tracked, the error of the sheet sizing in a normal condition is within +/-20 mm, if the included angle between a camera and a roller way changes due to vibration of the roller way, the change of the sheet sizing can also be caused, and the micro movement of the camera lens cannot be observed through naked eyes. In addition, since the sheet surface is not smooth enough, a situation in which a signal is lost due to diffused reflection easily occurs.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a method and a system for performing slab tracking measurement by using a laser speed measuring sensor.

The method for performing slab tracking measurement by using the laser speed measuring sensor comprises the following steps:

laser speed measurement: respectively adding a laser speed measuring sensor in front of and behind the cutting roller way, recording as a front laser speed measuring sensor and a rear laser speed measuring sensor, and starting the laser speed measuring sensors to measure speed when a blank exists in the middle of the cutting roller way;

a distance measuring and calculating step: the control unit identifies effective signals of the laser speed measuring sensor, integral calculation is carried out on the speed value according to the effective signals to obtain a moving distance value, the control unit identifies invalid signals of the laser speed measuring sensor, and an auxiliary encoder is used for calculating the moving distance value according to the invalid signals.

Preferably, the method for performing slab tracking measurement by using the laser speed measuring sensor further comprises the following steps: respectively installing hot metal detectors on two sides of the cutting roller table, recording the hot metal detectors as a left hot metal detector and a right hot metal detector, determining a detection distance between the left hot metal detector and the right hot metal detector, wherein the detection distance can correct the casting length, moving a cast blank through the cutting roller table after pouring is started, and correcting the casting length according to the actual metallurgical length if a control unit receives a signal of the left hot metal detector, wherein the metallurgical length is the length from a crystallizer liquid surface of a continuous casting machine to the tail end of the cast blank; and if the control unit receives the signal of the hot metal detector on the right side, correcting the casting length according to the detection distance.

Preferably, the movement distance value is calculated according to the following formula:

wherein s represents a movement distance value;

c represents the propagation speed of light in the atmosphere;

dt represents the differentiation over time t;

t₀the time required for the light to travel back and forth to two measurement points once.

Preferably, the slab length is calculated by:

L＝S-A(t)-B(t)cosβ

wherein L represents a slab length;

s represents the distance between the rear laser speed measuring sensor and the fixed standard plate;

beta represents the included angle between the rear laser speed measuring sensor and the horizontal plane;

a (t) represents the distance between the front laser speed measuring sensor and the fixed standard plate;

and B (t) represents the distance between the rear laser tacho sensor and the sheet blank head.

Preferably, theThe above-mentioned

The system for performing slab tracking measurement by using the laser speed measuring sensor provided by the invention comprises the following steps:

the laser speed measuring module: respectively adding a laser speed measuring sensor in front of and behind the cutting roller way, recording as a front laser speed measuring sensor and a rear laser speed measuring sensor, and starting the laser speed measuring sensors to measure speed when a blank exists in the middle of the cutting roller way;

the distance measuring and calculating module comprises: the control unit identifies effective signals of the laser speed measuring sensor, integral calculation is carried out on the speed value according to the effective signals to obtain a moving distance value, the control unit identifies invalid signals of the laser speed measuring sensor, and an auxiliary encoder is used for calculating the moving distance value according to the invalid signals.

Preferably, the tracking measurement module is further included: respectively installing hot metal detectors on two sides of a cutting roller way, recording the hot metal detectors as a left hot metal detector and a right hot metal detector, determining a detection distance between the left hot metal detector and the right hot metal detector, wherein the detection distance can correct the casting length, after pouring is started, moving a cast blank through the cutting roller way, and correcting the casting length according to the actual metallurgical length if a control unit receives a signal of the left hot metal detector, wherein the metallurgical length is the length from the liquid level of a crystallizer of a continuous casting machine to the tail end of the cast blank; and if the control unit receives a signal of the right hot metal detector, correcting the casting length according to the detection distance.

Compared with the prior art, the invention has the following beneficial effects:

1. the problem of error caused by the slipping of the length measuring roller can be solved, and whether the slipping problem exists is reversely deduced according to the precision tracking information;

2. the tracking of the abnormal position is more accurate, the length loss of the waste billet can be reduced, a length measuring roller is omitted, and the maintenance cost of mechanical equipment is reduced;

3. after the tracking precision is improved, the cast length information is more accurate, the plate length information is more accurate, and the size of the flame cutting slit can be obtained through calculation;

4. the casting length data of the long roll is more consistent with the actual situation, and convenience and solid foundation can be provided for the work of quality analysis, model development and the like.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a schematic diagram of a three-step process of the present invention.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

The method is implemented by the following steps:

laser speed measurement: respectively adding a laser speed measuring sensor in front of and behind the cutting roller way, recording as a front laser speed measuring sensor and a rear laser speed measuring sensor, and starting the laser speed measuring sensors to measure speed when a blank exists in the middle of the cutting roller way;

a distance measuring and calculating step: the control unit identifies effective signals of the laser speed measuring sensor, integral calculation is carried out on the speed value according to the effective signals to obtain a moving distance value, the control unit identifies invalid signals of the laser speed measuring sensor, and an auxiliary encoder is used for calculating the moving distance value according to the invalid signals.

Tracking and measuring: respectively installing hot metal detectors on two sides of the cutting roller way, recording the hot metal detectors as a left hot metal detector and a right hot metal detector, determining a detection distance between the left hot metal detector and the right hot metal detector, wherein the detection distance can correct the casting length, after pouring is started, moving a cast blank through the cutting roller way, and correcting the casting length according to the actual metallurgical length if a control unit receives a signal from the left hot metal detector, wherein the metallurgical length is the length from the liquid level of a crystallizer of a continuous casting machine to the tail end of the cast blank; if the control unit receives the signal of the right hot metal detector, the casting length is corrected according to the detection distance.

Regarding detection, as shown in fig. 1, laser tachometer sensors (LVS0A and LVS0B) are respectively added before and after a cutting roller table to directly detect the moving speed of a blank or a plate, and the detection range is large. The laser speed measuring sensor is a novel measuring sensor based on optical wave distance measurement, has very wide application in the detection field, and can be used for online cutting of plates and pipes and measuring the speed of cables or sand paper; the device belongs to a non-contact measurement mode, so that the device is suitable for measuring the speed of sensitive or untouchable objects, such as textiles such as flannelette and fur, coating and viscose surfaces, and foam rubber; it can also be used in the metal processing industry, such as measuring the speed of steel, measuring the double pumping speed, controlling the coating process, etc.

During measurement, after the PLC receives effective signals of LVS0A and LVS0B, the PLC performs measurement according to a formulaA distance value of the movement of the cast blank can be obtained, wherein c is the propagation speed of light in the atmosphere, t₀The time required for the light to travel back and forth to two measurement points once. Meanwhile, the existing hot metal detectors arranged at fixed positions on two sides of the roller way are utilized. After pouring is started, after the cast blank moves the cutting roller way, once the PLC receives a signal that the head of the blank appears, the length from the position to the lower opening of the crystallizer is a fixed value, and then the cast length information can be corrected according to the data.

With respect to the calculation, referring to Table 1, since the measurement of the blank is based on the lightwave ranging, it is known that the distance S between LVS0B and the standard plate, and the included angle β between the reference plate and the horizontal planeThe lengths L of the blanks A (t), B (t) and L measured by the laser ranging sensors may be calculated according to the formula L ═ S-A (t) -B (t) cos beta, where L is Andt_A，t_Brepresenting the time required for the light to make one round trip between the sensor and the measurement point.

Referring to Table 2, the scanning period T of the PLC is 10ms, the pulling speed V in the pouring process is 1.2m/min, and the moving distance L of the cast blank in one scanning period_aIs 0.2 mm. Detection error C of laser speed measurement sensor_dLess than 0.05%, i.e., the length L of the cast blank moved_bAt 10m, the error of the sensor is multiplied by the length of the sheet to obtain a length error of 5 mm.

In the PLC, the existing encoder signal, the photoelectric switch signal and the newly added tachometer signal are integrated, and when the tachometer signal is effective, the signal of the tachometer is used for calculating the increment of the moving distance; when invalid, the encoder signal is used to calculate the distance increment of movement.

TABLE 1 associated parameters in the calculation of cast Length

Standard distance between standard plate and velocity measuring sensor LVS0A	A(t)
		Distance between standard plate and velocity measuring sensor LVS0B	S
Distance between velocity measuring sensor LVS0B and head of blank	B(t)
		The included angle between the velocity measurement sensor LVS0B and the horizontal plane	β
Length of continuous casting blank	L

TABLE 2 actual values of relevant parameters used according to 3CC

Pulling speed V	Scanning period T	Distance of movement La	Detection error Cd	Length of movement Lb	Calculating the error Ld
						1.2m/min	10ms	0.2mm	0.05％	10m	5mm

In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.