RU2641936C1 - Device for measuring machine roll solution for continuous casting of billets - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: device for measuring machine roll solution for continuous casting of billets contains a rod (3) with a fixed jaw (9) and magnets (6), two laser emitters (7) with an alternator line placed on a fixed sponge (9), and a web camera (4) connected to the interface (2) of USB 2.0 or USB 3.0 type with a tablet computer (1). The device is installed so that the rod contacts both rolls from the side, the fixed jaw is attached by the magnet to the bottom roll from the top, two laser emitters (7) are located on a projecting portion of the rod so that roller lines get in the field of web camera vision. The image from the web camera is analysed, and on the basis of this analysis, the distance between the rollers is calculated by the tablet computer (1).

EFFECT: increased measurement rate due to eliminated dismantling of the machine for continuous casting of billets and increased measurement accuracy at low cost of the measuring device.

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Description

The invention relates to the metallurgical industry and can be used to measure a solution of rolls in continuous casting mechanisms of metals, in particular steel.

To reduce the number of rejects of manufactured products produced by using a continuous casting machine (CCM), constant monitoring of the distance between the rolls of this machine is necessary. For accurate measurement of the distance between the rolls, it is necessary to determine the boundary of the roll as correctly as possible.

A common problem in industry and production, the stage of choosing a measuring system for controlling the parameters of working mechanisms is one of the most important constituent elements of the entire process of production, since the quality of the goods produced directly depends on the accuracy of the settings of the devices with which these products are produced.

The CCM operators, constantly monitoring the stability of the gap, have a need to create and introduce into production a measuring device that allows not only quick measurement with sufficiently high accuracy of 0.1 mm, but also penetrating with the aim of measurement to the most inaccessible places and making measurements in conditions of absolute darkness.

To carry out the process of accurate calibration of hard-to-reach mechanisms requires the use of portable small-sized measuring devices that reduce the diagnostic time and minimize the error of all measurements to a minimum. The use of mechanical measuring equipment does not always allow us to achieve the necessary measurement accuracy, so the idea arose of using a mobile vision system to constantly control the distance between the caster rolls without completely stopping and dismounting it.

The vision system in this application is understood as a combination of software and hardware that allows accurate measurements of the gap and displays all the information obtained as a result of the measurements regarding the clearance and radius of the roll, in a form understandable to the CCM operator.

CCM (Continuous Casting Machine) is a mechanism, the process of casting blanks on which is as follows: after the metal passes through the rolls, the thickness of the metal ingot becomes equal to the distance (gap) between the rolls. To control the passage of metal through the rolls, it is necessary to regularly measure the gap between the rolls. In practice, this task is quite time-consuming and quite time-consuming, in addition, the accuracy of the measurement results, with the required accuracy of up to 0.1 mm, does not always meet the requirements and standards of the process. Currently, there are two main measurement methods in production and, accordingly, two measuring devices are used to control the gap.

Micrometer caliper

Special seed nozzle

Mainly, the task of measuring the gap is currently being solved by micrometric gages (See www.standartgost.ru GOST 10-88), which, on the one hand, allow you to measure the distance with an accuracy of 0.1 mm, but on the other hand, this accuracy directly depends on the correctness of the placement of the cage meter at the facility by the CCM operator. The problem when measuring with the caliper is that a person puts the caliper "by eye", therefore, in this case, it is quite difficult to talk about obtaining high accuracy measurements. Moreover, taking into account the fact that to measure the distance between the rolls, it is necessary to stop the machine and remove the necessary pairs of rolls from it, it can be confidently stated that the existing measurement method is too time-consuming and leads to significant temporary and, consequently, material losses. However, if you do not constantly monitor the parameters of the machine, then over time it will begin to produce defective products, which is unacceptable due to the huge material losses due to marriage.

In addition to micrometric calipers that are universally used in the process of measuring the internal dimensions of parts by the absolute method, there is a special seed nozzle that allows you to measure various parameters of caster rolls by rolling it through the entire caster, see Roll Gap Checker uralmash, see e-mail: juergen meisel @ votron.com.

The closest analogue of the claimed invention is a device for measuring a roll solution containing a laser emitter, see JP 0057132009, B21B 38/10, 08.16.1982, in which the eccentricity of the rolls is determined using laser radiometry as a result of wear and the appearance of backlash.

Disadvantage: the device is used only in statics, i.e. when the machine stops.

An object of the invention is: to increase the measurement speed without the need to disassemble the machine, to increase the measurement accuracy of less than 0.1 mm, as well as low cost.

The technical result is achieved by creating a device based on a measuring line (as the authors called).

To solve this problem, a device for measuring a solution of rolls is proposed, consisting of a rod with magnets, one web camera, two laser emitters, forming a measuring ruler that is connected to the rolls with magnets and the protruding part of the rod so that the rod itself touches both rolls side, and the protruding part of the rod is attached to the lower roll on top. Two laser emitters with a line generator are located on the protruding part of the bar so that the lines on the roll fall into the field of view of the web camera, which are connected to the tablet computer via the USB 2.0 / 3.0 communication interface.

The drawing shows the structural-kinematic diagram of the device, which shows:

1 - tablet computer (PC), 2 - USB 2.0 / 3.0 communication interface of the web camera with the tablet computer, 3 - rod, 4 - web camera, 5 - temperature sensor, 6 - magnets, 7 - laser emitters, 8 - rolls , 9 - fixed sponge (protruding part of the rod).

The batteries of the components of the device are not conventionally shown.

The circuit has the following connections.

The rod 3 with magnets 6, with a web camera 4, with two laser emitters 7 form a measuring ruler, which is connected to the rollers 8.1 and 8.3 with magnets 6 and the protruding part of the rod 3 so that the rod 3 itself touches both rollers 8.1 and 8.3 side, and the protruding part of the rod 9 is based on the lower roller 8.3 from the top. Two laser emitters of line 7 are located on the protruding part of the rod 9 so that the lines on the roll 8.3 fall into the field of vision of the web camera 4, which are connected to the tablet computer 1 via the USB 2.0 / 3.0 2 communication interface.

The device operates as follows. They assemble the device diagram at the beginning for measuring the solution of rolls 8.1 and 8.3, turn on PC9, connect the measuring ruler to PC9, wait for the software to load.

Software Interface Description

- Button “Measure”: carries out the process of measuring parameters and entering them into the database;

- A video image from the camera and an indicator of the angle of the ruler;

- Section “Measurements”: the last measured values for operator control are displayed;

- Section "Positioning on rolls": used to set the system of measurement identifiers (No. of a pair of rolls, No. of a section, No. of a stream and No. of a machine);

- Temperature in the measurement area;

- The degree of charge of the system’s battery (“Battery” chart).

Measurement Algorithm:

- Install the measuring device on the rolls to the stop;

- Using the corresponding “+” and “-” buttons, set the positioning identifiers (No. of rolls pair, Section No., Stream No. and Machine No.) or by clicking on the white text fields, in the window that opens, dial the required number and press “Enter”;

- Check the video image displayed on the tablet screen so that both laser lines are fully visible.

- Align the system, guided by the indicator of the angle of inclination (the yellow indicator should be in the green area);

- Press the “Measure” button and check the result in the “Measurements” section. The results will be automatically entered into the database. If necessary, the last data entered into the database can be deleted using the "Delete last measurement" button.

Stages of processing the image received from the web camera.

We describe the main stages in image processing to determine the equation of the visible boundary of the roll, which is then used directly in the calculation of the gap value.

In the first step, line-by-line image compression occurs by grouping pixels. This is done to eliminate most noise and a significant increase in speed.

In the second step, the brightness of the pixels is measured line by line. When reading the brightness, the blue channel is ignored, since it was experimentally revealed that most of the noise in the camera used is blue.

Since the laser line is analyzed, the brightness values are lower, the farther from the center of the line. In this step, we get the brightness distributions for each row.

Further, the distributions are cut off in the maximum region, the size of which is slightly larger than the laser width, then the points are filtered in a small region near the minimum brightness and interpolated by spline interpolation.

At the next step, the luminance values of the resulting distribution are recalculated in such a way that the sum is one.

where b is the brightness at a given point;

p is the probability of finding the center of the line at a given point.

Therefore, the obtained values are the probability of finding the center of the laser at a given point.

Next, the expected coordinate of the center of the line in this line is calculated by summing the products of probability by the coordinate.

where M is the expected center of the line in a given line, peak;

x - coordinate of the point along the abscissa, peak;

p is the probability of finding the center of the line at a given point.

These actions are performed for all lines, as a result, a set of points is obtained, according to which the line is constructed by approximation by the least squares method.

The indicated image processing algorithms make it possible to accurately determine the equations of laser lines, which, in turn, is very important for the exact calculation of the gap, since further mathematical calculations are mainly based on the equation of laser lines.

Thus, it can be seen that the device by its design is extremely simple, convenient to use and has a low cost, therefore, fully complies with the basic economic criterion of "cost - effectiveness".

Claims (1)

A device for measuring a solution of rolls of a continuous casting machine containing a rod with a fixed sponge configured to be placed on one of the rolls and magnets for interacting the rod with two rolls, two laser emitters with a line generator placed on a fixed sponge, and a web camera connected by an interface such as USB 2.0 or USB 3.0 with a tablet computer, and configured to fix both laser lines on another roll.

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