JP7207367B2 - Thick steel plate warp detection method and plate warp detection system - Google Patents

Description

The present invention provides a method for detecting warpage at the tip and tail ends of a thick steel plate in order to avoid collisions between equipment installed in the production line and the tip and tail ends of the thick steel plate. and related to sensing systems.

A thick steel plate manufactured by hot-rolling a heated steel slab or cast slab with a hot rolling mill is conveyed on a roller table and cooled. and cut into lengths to finish thick steel plate products. In this thick steel plate, warping occurs at the front end (front end in the conveying direction) and the tail end (back end in the conveying direction) due to strain generated during hot rolling. Sometimes. This board warp includes both a case of warping vertically upward (referred to as "upward warp") and a case of warping vertically downward (referred to as "downward warp").

A sensor such as a laser plate thickness gauge using a laser beam is installed between the rolls of the roller table of the steel plate production line. Both sensors are installed below or above the pass line of the roller table, but if the plate warping of the thick steel plate is large, the tip or tail of the warped plate collides with the sensor installed between the rolls. The problem is that the sensor is damaged.

In order to solve such problems, Patent Literature 1 proposes a flatness measuring device that measures the flatness of a conveyed steel plate using a non-contact rangefinder. The flatness measuring apparatus proposed in Patent Document 1 includes a plurality of non-contact rangefinders arranged between adjacent conveying rolls, and the influence component of the variation of the pass line of the steel sheet from the output of the non-contact rangefinder. A first computing unit to be removed, and based on the output of the first computing unit, strain in the longitudinal direction of the steel plate, strain in the width direction, maximum steepness, plate warpage at the tip or tail end, 2 m strain, or 1 m strain and a second computing unit that computes at least one.

JP-A-7-234121

However, the above prior art has the following problems.

That is, Patent Document 1 aims to ensure the quality of the steel sheet by measuring the amount of warpage at the leading end and the trailing end, so the measurement result (warpage amount) is used to stop the production line, and the equipment is stopped. No design is made to prevent damage. Moreover, Patent Literature 1 evaluates the measured amount of warpage of the steel sheet as it is, and has a problem that the deflection amount of the steel sheet and the like are not taken into consideration. Considering the amount of deflection between the rolls of the steel sheet, the amount of downward warp becomes larger than the measured value, and the risk of collision with the sensor installed between the rolls increases.

The present invention has been made in view of the above circumstances, and its object is to prevent the leading end and trailing end of a warped thick steel plate from colliding with a sensor or the like installed between rolls of a roller table. In addition, the warp amount of the thick steel plate is accurately measured at the tip and tail ends of the thick steel plate in consideration of the amount of deflection of the thick steel plate, and the production line is stopped based on the measured value of the warp amount. An object of the present invention is to provide a detection method and a board warp detection system.

The gist of the present invention for solving the above problems is as follows.

[1] Using a non-contact rangefinder, measure the distance to the surface of a thick steel plate conveyed through a thick steel plate production line,
Using the distance measurement value by the non-contact rangefinder and the line speed information of the production line, determine the shape of the thick steel plate (upward or downward warpage),
The distance measured by the non-contact rangefinder, the self-weight deflection due to the loss of support for the leading end and the trailing end of the thick steel plate at the opening between the rolls of the production line, and the distance measurement in the downward warping thick steel plate Deflection under the weight of the steel plate is used to calculate the amount of upward or downward warpage of the steel plate,
A method for detecting warpage of a thick steel plate, comprising stopping the production line when the calculated amount of upward warpage or the amount of downward warpage exceeds each of preset threshold values.

[2] A non-contact rangefinder installed vertically above or below a thick steel plate production line to measure the distance to the surface of the thick steel plate conveyed through the production line;
determining the shape (upward or downward) of the thick steel plate based on the distance measured by the non-contact rangefinder and the line speed information of the production line;
The distance measured by the non-contact rangefinder, the self-weight deflection due to the loss of support for the front end and the tail end of the thick steel plate at the opening between the rolls of the production line, and the distance measurement in the downward warped thick steel plate Deflection under its own weight is used to calculate the amount of upward or downward warpage of a thick steel plate, and
a board warp detection computer that transmits a signal to stop the production line when the calculated amount of warp or the amount of warp exceeds preset threshold values;
A plate warp detection system for thick steel plates, characterized by comprising:

[3] The plate warp detection of the thick steel plate according to [2] above, wherein the non-contact rangefinder is installed vertically above the production line and vertically above the rolls of the production line. system.

According to the present invention, since the amount of warp and the amount of warp of the thick steel plate are calculated in consideration of the amount of deflection of the steel plate, the actual amount of warp and the amount of warp of the thick steel plate can be obtained accurately. In addition, when the calculated amount of warpage and amount of warp exceeds the respective threshold values, the production line is stopped, so that the tip and tail ends of the thick steel plate and the equipment installed between the rolls do not collide in advance. are prevented and damage to equipment is avoided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing an embodiment of the present invention, and is a schematic diagram in which a plate warpage detection system according to the present invention is installed in a thick steel plate production line; It is a schematic diagram which shows the shape discrimination|determination method of the front-end|tip part of a thick steel plate. It is a schematic diagram showing a method of calculating the amount of warp at the tip portion of the warp thick steel plate. It is a schematic diagram showing a method of calculating the amount of downward warp at the tip portion of the downwardly warped thick steel plate. FIG. 4 is a flow diagram showing a method of detecting a bowed thick steel plate and a method of issuing an alarm by classifying the leading end and the trailing end of the thick steel plate. FIG. 4 is a diagram schematically showing self-weight deflection due to loss of support for the front end of the thick steel plate in the opening between rolls. FIG. 10 is a diagram schematically showing self-weight deflection of a downward-curved thick steel plate during distance measurement with a laser rangefinder.

BEST MODE FOR CARRYING OUT THE INVENTION A method for detecting warpage of a thick steel plate and a warp detecting system for a thick steel plate according to the present invention will be specifically described below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing an embodiment of the present invention, and shows a schematic diagram of an example in which a plate warp detection system according to the present invention is installed in a thick steel plate production line. As shown in FIG. 1, the thick steel plate manufacturing line through which the thick steel plate 6 is conveyed is configured by combining a plurality of roller tables having a plurality of rolls 4 arranged side by side. A laser plate thickness gauge 5 is installed in this thick steel plate production line. A detection system 1 is installed.

The laser plate thickness gauge 5 is installed between the rolls 4 of the production line, and the laser plate thickness measuring head 5a is installed at a position higher than the pass line of the production line. A laser plate thickness gauge lower measuring head 5b is installed at a position lower than the pass line. The thickness of the thick steel plate 6 moving in the production line is measured continuously by the laser light 8 emitted from the laser plate thickness upper measuring head 5a and the laser light 9 emitted from the laser plate thickness gauge lower measuring head 5b. It is designed to be measured systematically. In the present embodiment, an example will be described in which the tip and tail ends of the thick steel plate 6 conveyed through the production line are prevented from colliding with the laser plate thickness gauge 5, particularly the laser plate thickness gauge lower measuring head 5b.

A plate warp detection system 1 according to the present invention includes a non-contact rangefinder 3 installed vertically above a roll 4 on the upstream side in the conveying direction at a predetermined distance from a laser plate thickness gauge 5, and this non-contact rangefinder. and a warp detection calculator 2 into which the distance measurement value to the upper surface of the thick steel plate 6 measured in 3 is input. Further, the sheet warp detection computer 2 receives line speed information of the production line from a pulse generator (not shown) that measures the rotation speed of the roll 4, that is, the movement speed of the thick steel plate 6 conveyed through the production line. It is designed to be entered.

The non-contact rangefinder 3 can also be installed vertically below the thick plate manufacturing line. When the non-contact rangefinder 3 is installed vertically below the thick steel plate production line, the non-contact rangefinder 3 measures the distance to the bottom surface of the thick steel plate 6 . As the non-contact rangefinder 3, a laser rangefinder, an ultrasonic rangefinder, or the like can be used. In this embodiment, an example in which a laser rangefinder 3 a installed vertically above the roll 4 is used as the non-contact rangefinder 3 will be described below.

The laser rangefinder 3a irradiates the upper surface of the thick steel plate 6 with a laser beam 7 at predetermined intervals, and measures the distance to the upper surface of the thick steel plate 6. FIG. Since the vertical vibration of the thick steel plate 6 moving in the production line is relatively suppressed when it passes the position of the roll 4, by installing the laser rangefinder 3a vertically above the roll 4, the thick steel plate The distance to the upper surface of 6 can be measured relatively stably and accurately.

The warp detection calculator 2 calculates the measured distance to the upper surface of the steel plate 6 input from the laser distance meter 3a and the line speed information of the production line input from a pulse generator (not shown) or the like. Then, the warpage of the thick steel plate 6 is detected. This warp detection calculator 2 receives the distance measurement value to the upper surface of the steel plate 6 input from the laser distance meter 3a, and the line speed information of the production line input from a pulse generator (not shown) or the like. It has a memorization function. In addition, the board warp detection calculator 2 arbitrarily sets thresholds for the warp and the warp, and when the calculated amount of warp or the amount of warp exceeds the preset thresholds, a signal to stop the production line. to stop the production line.

Hereinafter, individual features of the method for detecting warpage of a thick steel plate and the warp detection system for a thick steel plate according to the present invention will be described.

<Method for Determining Upward Warp and Downward Warp>
In the present invention, one or a plurality of laser rangefinders 3a in the width direction of the thick steel plate 6 detect upward and downward warpage of the thick steel plate 6. FIG. The warp detection calculator 2 determines the shape of the thick steel plate 6 (inclination of the surface of the thick steel plate 6) using the distance measurement value and the line speed information obtained by the laser rangefinder 3a. That is, the warp detection computer 2 detects the warp of the thick steel plate 6 using the upward warp detection logic and the downward warp detection logic.

First, the warp detection calculator 2 detects the tip of the thick steel plate 6 and then determines the shape of the thick steel plate 6 . FIG. 2 shows a schematic diagram of a method for determining the shape of the tip of the thick steel plate 6. As shown in FIG. When determining the shape, the plate warp detection calculator 2 calculates the height of the upper surface of the thick steel plate 6 from the pass line based on the distance measurement to the upper surface of the thick steel plate, as shown in FIG. The calculated height of the thick steel plate 6 from the pass line is compared with the previous calculated value. In the calculated value of the height from the pass line of the tip of the steel plate 6, when compared with the previous calculated value, if the height from the pass line tends to decrease, it is considered to be warping (see FIG. 2(A)). If the height from the pass line tends to increase, it is determined to be downward warping (see FIG. 2B).

At the tail end of the thick steel plate 6, on the contrary, when compared with the immediately preceding calculated value, if the height from the pass line tends to increase, it is determined to be warping, and if the height from the pass line tends to decrease. It is determined to be warped downward. A range of about 1 m from the tip end and the tail end is evaluated for determining the shape of the thick steel plate 6 .

After that, the upward warp amount and the downward warp amount are calculated according to the determined shape. FIG. 3 shows a method of calculating the amount of warp at the tip of the warped thick steel plate. For the warped thick steel plate, the difference between the calculated maximum height of the thick steel plate 6 from the pass line and the thickness of the thick steel plate is calculated as the warp amount. Further, FIG. 4 shows a method of calculating the amount of warp at the tip portion of the warp thick steel plate. In the case of the downward warp thick steel plate, the difference between the calculated maximum height and the calculated minimum height is calculated as the amount of downward warp within the range where there is a possibility of slipping between the rolls. When the calculated amount of warp or warp exceeds the threshold value, the board warp detection computer 2 issues a signal to stop the production line.

Here, the “range where there is a possibility of slipping between the rolls” is a distance determined according to the installation position of the equipment installed between the rolls, such as the laser plate thickness gauge 5 . For example, when considering a collision due to warping of the tip of a thick steel plate, the "range where there is a possibility of slipping between rolls" is the installation position of the equipment installed between the rolls and the upstream of the production line with respect to the equipment. It is the distance from the center position of the roll 4 installed just before the side.

The detection of the amount of warpage of the downward warping thick steel plate and the transmission of the production line stop signal (hereinafter also referred to as "alarm transmission") will be further described.

A laser thickness gauge lower measuring head 5b (hereinafter also simply referred to as “laser thickness gauge 5b”) with which the front end and tail end of the thick steel plate 6 may collide is installed at the center position between the rolls of the production line. It is often installed with a shift forward and backward in the transport direction of the production line.

In the thick steel plate production line targeted in the present embodiment, as shown in FIG. 6 (detailed description of FIG. 6 will be described later), the distance between the rolls of the roller table is 1000 mm, and the line conveying of the laser plate thickness gauge 5b The distance from the leading edge in the direction to the center of the roll immediately before the upstream side in the line conveying direction with respect to the laser plate thickness gauge 5b is 613 mm. On the other hand, the distance from the rearmost end of the laser plate thickness gauge 5b in the line transfer direction to the center of the roll immediately behind the laser plate thickness gauge 5b on the line transfer direction downstream side is 663 mm. That is, even if the amount of downward warpage of the tip and tail ends of the thick steel plate 6 is the same, considering the deflection of the thick steel plate 6, the tail end of the thick steel plate 6 contacts (collides) with the laser plate thickness gauge 5b. easy.

Considering this difference, it is preferable to implement the method of detecting a bowed thick steel plate and issuing an alarm based on the flow chart of FIG. In other words, since the tip and tail ends of the thick steel plate 6 have different warp detection methods, they are shown separately in the flow chart. FIG. 5 is a flow diagram showing a method of detecting a bowed thick steel plate and a method of issuing an alarm, divided by the front end and the tail end of the thick steel plate.

In the process for detecting the tip of the thick steel plate 6, after detecting the tip of the thick steel plate (S1), it is determined whether or not the thick steel plate is a warped thick steel plate (S2). Using the line speed information, add the difference value of the height from the pass line of the measured steel plate (immediately measured value - current measured value) within a certain range, and if the added value becomes negative, that is, the steel plate If the height from the pass line of 6 tends to increase, it is determined that the steel plate is a thick steel plate with its tip downwardly warped (S3). For a thick steel plate determined to have tip downward warp, the amount of downward warp is calculated from the measured height (measured maximum height - (measured minimum height ≒ tracking plate thickness)) in the range of 613 mm from the tip (S4). . The calculated downward warp amount is compared with the downward warp threshold (S5), and if the calculated downward warp amount exceeds the downward warp threshold, an alarm is issued (S6). The threshold will be described later.

In the tail end downward warping detection processing of the thick steel plate 6, after detecting the position 663 mm before the tail end of the thick steel plate (S7), it is determined whether or not the thick steel plate is a downward warping thick steel plate (S8). Using the line speed information, the difference value of the height from the pass line of the measured steel plate (immediately measured value - current measured value) is added within a certain range, and if the added value becomes positive, that is, the steel plate If the height from the pass line is decreasing, it is judged to be a thick steel plate with tail end downward warp (S9). For a thick steel plate determined to have tail end warpage, the amount of downward warpage is calculated from the measured height (measured maximum height - (minimum height ≒ tracking plate thickness)) in the range of 663 mm from the tail end (S10 ). The calculated downward warp amount is compared with the downward warp threshold (S5), and if the calculated downward warp amount exceeds the downward warp threshold, an alarm is issued (S6).

As described above, in the thick steel plate production line targeted in the present embodiment, the range for obtaining the amount of downward warp is from the rolls immediately before and after the production line to the laser plate thickness gauge lower measurement head for the laser plate thickness gauge 5b. The tip of the thick steel plate was set to a range of 613 mm from the tip, and the tail end of the thick steel plate was set to extend from a position 633 mm in front of the tail end to the tail end. The threshold value is set with reference to the height difference from the pass line of the laser plate thickness measuring head 5a and the laser plate thickness measuring head 5b.

In the above description, the range for determining the amount of downward warp is that the front end of the thick steel plate is a range of 613 mm from the front end, and the tail end of the thick steel plate is from a position 633 mm in front of the tail end to the tail end. , which is a numerical value determined based on the structure of the thick plate manufacturing line and the installation position of the laser plate thickness gauge 5, which is the object of this embodiment. That is, in the present invention, the range for determining the amount of downward warp is determined according to the structure of the thick plate production line and the position of the equipment installed in the thick plate production line, and the present invention is limited to the above numerical range. not to be

<Elastic Deformation of Thick Steel Plate (Self-weight Deflection Due to Loss of Support for Tip and Tail End Between Rolls)>
When the thick steel plate 6 passes through the installation position of the laser plate thickness gauge lower measuring head 5b, that is, the opening between the rolls, the leading end and the trailing end of the thick steel plate 6 are not supported, so self-weight deflection occurs. When self-weight deflection occurs, the front end and tail end of the thick steel plate 6 add the self-weight deflection and approach the lower measuring head 5b of the laser plate thickness gauge, so it is necessary to correct the deflection amount according to the plate thickness. There is

As shown in FIG. 6, the distance from the immediately preceding roll 4a on the upstream side in the conveying direction to the deepest part (the most distal end in the line conveying direction) of the laser plate thickness gauge 5b is 613 mm, and the tip of the thick steel plate is at that position. The amount of deflection is determined as "δ ₁ " when the tip of the thick steel plate comes into contact with the downstream roll 4b in the conveying direction, and "δ ₂ " as the deflection amount. In FIG. 6, the distance from the pass line to the upper surface of the lower measurement head 5b of the laser thickness gauge is 82.5 mm. In addition, FIG. 6 is a diagram schematically showing self-weight deflection due to loss of support for the tip of the thick steel plate at the opening between the rolls.

The amount of deflection δ is the same as in the case of a uniformly distributed load on a cantilever beam in structural mechanics, and is calculated using the following formula (1).

The thickness of the thick steel plate is 4.5 mm at its thinnest. Taking the thinnest case as _an example, the amount of _{deflection δ} is calculated. _The smaller the plate thickness of the thick steel plate, the larger the deflection amount δ.

In the present invention, from the viewpoint of reliably preventing collision with the _lower measurement head 5b of the laser plate thickness gauge, the amount of deflection δ2 is corrected as the amount of deflection δ due to the loss of support at the leading end and the trailing end. Correction is also performed according to the plate thickness of the thick steel plate 6 .

<Elastic Deformation of Thick Steel Plate (Self-weight deflection during distance measurement in downward warped thick steel plate)>
In the case of a bowed thick steel plate, deflection of the thick steel plate occurs even during rangefinder measurement by the laser rangefinder 3a. A flat thick steel plate without deformation is conveyed while being supported by each roll 4 installed at intervals of 1 m. However, in the case of a thick steel plate that is greatly warped in the longitudinal direction, as shown in FIG. is also vertically above. At this time, the thick steel plate is bent due to its own weight, and the shape of the thick steel plate in this state is measured by the laser distance meter 3a. As a result, there is a possibility that the amount of downward warp may be underestimated.

In FIG. 7, the deflection amount Δ at the position where the distance to the steel plate surface was measured by the laser rangefinder 3a is shown as an underestimation at that location, which is different from the maximum deflection amount Δ. In FIG. 7, the maximum value of the amount of deflection Δ exists on the upstream side in the transport direction from the position where the laser rangefinder 3a is installed. Therefore, in the present invention, the maximum value of the amount of deflection Δ is quantitatively determined and corrected. FIG. 7 is a diagram schematically showing the bending of the downward-curved thick steel plate during distance measurement by the laser rangefinder 3a.

The thick steel plate 6 is supported by the rolls 4 at a certain distance from the leading end of the thick steel plate 6, and the thick steel plate 6 exists above the pass line in the vertical direction. The amount of deflection Δ at this time is the same as in the case of a uniform load on a continuous beam in structural mechanics, and is calculated using the following formula (2).

Since the deflection amount Δ increases as the plate thickness of the thick steel plate 6 decreases, consider the deflection amount Δ in the case of a minimum plate thickness of 4.5 mm. Further, as the distance between the fulcrums increases, the amount of deflection Δ increases. When the distance between the fulcrums exceeds 3 m, the amount of deflection Δ exceeds 100 mm, so the distance between the fulcrums is considered to be 3 m or less.

When the distance between the fulcrums is 1 m, the amount of deflection Δ(0.633)=1.19 mm, and when the distance between the fulcrums is 2 m, the amount of deflection Δ(0.633)=19 mm. In the present invention, the correction is performed according to the thickness of the thick steel plate 6, and the self-weight deflection amount Δ during distance measurement in the downward-curved thick steel plate is
It was decided to perform correction of 19 mm at the maximum.

<About the threshold>
The warp threshold is 0.8× _LU or less, where _LU (mm) is the distance between the pass line and equipment installed above the pass line, such as the laser plate thickness measuring head 5a. value. By setting the warpage threshold to 0.8 x _LU or less, even if the steel plate vibrates on the pass line, the collision between the equipment installed above the pass line and the tip and tail of the steel plate is prevented. be done. In the case of a warped thick steel plate, the self-weight deflection amount δ due to the lack of support for the tip and tail ends acts favorably against the collision between the equipment and the tip and tail ends of the thick steel plate.

The downward warp threshold is set by setting the distance between the equipment installed below the pass line and the pass line, such as the laser plate thickness gauge lower measuring head 5b, to _LL (mm), and the thickness of the thinnest thick steel plate to be conveyed. Assuming that the self-weight deflection amount δ is α (mm) and the self-weight deflection amount Δ of the thinnest thick steel plate to be conveyed is β (mm), it is preferable to set the value to " _LL (mm) - (α + β + 30)" or less. . 30 mm is a margin for avoiding collisions.

As described above, according to the present invention, the amount of upward warpage and the amount of downward warpage of the thick steel plate 6 are calculated in consideration of the amount of deflection of the thick steel plate 6. can be accurately obtained, and the production line is stopped when the calculated amount of warpage and amount of warpage exceeds the respective threshold values, so the tip and tail ends of the thick steel plate 6 and the rolls are installed Collision with the installed equipment is prevented and damage to the equipment is avoided.

A swing arm type stand is installed vertically above the steel plate manufacturing line, and five laser rangefinders are installed in the width direction of the line as non-contact rangefinders that measure the distance to the upper surface of the steel plate on this stand. installed. This makes it possible to measure the full width of a wide and thick steel plate. Also, the height from the pass line to the laser rangefinder was set to 500 mm. The laser rangefinder measured at 10 microsecond intervals.

The installation position of the laser rangefinder was determined by considering that the flow rate from the detection of warpage of the steel plate to the stoppage of the steel plate is 1.2m. position.

When board warpage of a thick steel plate is detected, it is necessary to stop conveying the thick steel plate to the table. In this case, the plate length of the thick steel plate varies from 6 to 26.5 m, and when warping is detected at the tail end of the thick steel plate, depending on the plate length, the tip position of the thick steel plate is measured by the laser plate thickness. pass the meter installation and enter the range of another roller table. Therefore, in order to reliably stop the roller tables with thick steel plates, the tracking sensors between the roller tables determine which roller tables have thick steel plates on them, and all the roller tables with thick steel plates on them are stopped. I made it Due to this stopping method, one of the roller tables stops while the steel plate is straddling between the roller tables, and the other roller table rotates, causing idle rotation of the rolls. It was possible to prevent scratches on the surface of the thick steel plate.

Using the plate warpage detection system for thick steel plates configured in this way, online verification was conducted on a thick plate production line equipped with a laser plate thickness gauge arranged as shown in FIG. . The distance from the roller table pass line to the laser thickness gauge upper measuring head is 117 mm, and the distance from the roller table pass line to the laser thickness gauge lower measuring head is 82.5 mm.

The inspection method is to double-check the visual judgment of the operator in the end shear operation room installed on the back of the laser plate thickness gauge and the actual data of the strain gauge installed on the back of the laser plate thickness gauge. was extracted, and it was collated whether or not the warp detection system according to the present invention accurately detected the warp thick steel plate.

In the first online operation, the upward warp threshold was set to 70 mm, and the downward warp threshold was set to 15 mm. Table 1 shows the results of the first online survey.

In the results of the first online survey, there were no undetected thick steel plates, but there were multiple over-detected thick steel plates. All of the excessively detected amounts of downward warpage of the thick steel plates were less than 18 mm.

Therefore, the second on-line measurement was performed by changing the downward warp threshold from 15 mm to 18 mm (the upward warp threshold was not changed). Table 2 shows the results of the second online survey.

In the second online test, there were no undetected or overdetected cases during the target period, and a concordance rate of 100% was achieved with the double check. After that, the process was implemented, and there was no damage to the laser plate thickness gauge due to the collision with the tip and tail ends of the thick steel plate.

REFERENCE SIGNS LIST 1 board warpage detection system 2 board warpage detection calculator 3 non-contact rangefinder 3a laser rangefinder 4 roll 5 laser board thickness gauge 5a laser board thickness measuring head 5b laser board thickness gauge lower measuring head 6 thick steel plate 7 laser beam 8 laser light 9 laser light

Claims (3)

Using a non-contact rangefinder, measure the distance to the surface of the steel plate conveyed through the steel plate production line,
Using the distance measurement value by the non-contact rangefinder and the line speed information of the production line, determine the shape of the thick steel plate (upward or downward warpage),
The distance measured by the non-contact rangefinder, the self-weight deflection due to the loss of support for the leading end and the trailing end of the thick steel plate at the opening between the rolls of the production line, and the distance measurement in the downward warping thick steel plate Deflection under the weight of the steel plate is used to calculate the amount of upward or downward warpage of the steel plate,
A method for detecting warpage of a thick steel plate, wherein the production line is stopped when the calculated amount of upward warpage or the amount of downward warpage exceeds respective preset threshold values. a non-contact rangefinder installed vertically above or below a thick steel plate production line for measuring the distance to the surface of the thick steel plate conveyed through the production line;
determining the shape (upward or downward) of the thick steel plate based on the distance measured by the non-contact rangefinder and the line speed information of the production line;
The distance measured by the non-contact rangefinder, the self-weight deflection due to the loss of support for the leading end and the trailing end of the thick steel plate at the opening between the rolls of the production line, and the distance measurement in the downward warping thick steel plate Deflection under its own weight is used to calculate the amount of upward or downward warpage of a thick steel plate, and
a board warp detection computer that transmits a signal to stop the production line when the calculated amount of warp or the amount of warp exceeds preset threshold values;
A plate warp detection system for thick steel plates, characterized by comprising: 3. The plate warp detection system for thick steel plates according to claim 2, wherein said non-contact rangefinder is installed vertically above said production line and vertically above the rolls of said production line.

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