JP5380879B2 - Automatic correction control method for differential thickness steel sheet and manufacturing method for differential thickness steel sheet - Google Patents

Description

  The present invention relates to an automatic correction control method and an automatic correction control device for a differential thickness steel plate in a thick steel plate straightening machine, and a method for manufacturing the differential thickness steel plate.

  It is necessary to reduce the thickness of the horizontal bulkhead of the cargo ship's hold from the bottom to the top in order to reduce the weight. A differential thickness steel plate with a difference is used.

  Such correction of the difference thickness steel plate whose shape changes in the plate thickness direction has been conventionally corrected using a press device, but there is a problem that productivity is low because the press device is an off-line process. On the other hand, when using a straightening machine using a pair of upper and lower work rolls or a roller leveler type straightening machine (hot leveler, cold leveler), which is used for on-line straightening of general steel plates, the straightening of the part where there is a difference in plate thickness The problem is how to control the quantity.

Patent Document 1 discloses a method of correcting a different thickness steel plate with a pair of upper and lower work rolls, and by lowering the plate passing speed when correcting the tapered portion of the different thickness steel plate than the plate passing speed when correcting the flat portion. In addition, a technique has been disclosed in which the reduction can be reliably corrected without a high-speed reduction cylinder.
JP 2007-7707 A

  In a straightening machine using a general roller leveler system, the steel sheet is not tracked. For this reason, in the correction of the difference thickness steel plate, the operator visually determines the stepped portion of the plate thickness, temporarily stops the correcting operation before the stepped portion, manually changes the amount of reduction, and then performs the correcting operation again. The actual situation is that correction work is performed by manual operation.

  The technique disclosed in Patent Document 1 is a method of correcting a different thickness steel plate by a pair of upper and lower work rolls, and the correction work efficiency is inferior compared to the case of using a roller leveler. In addition, in the technique disclosed in Patent Document 1, since the flat part length and the taper part length are known in advance from the order information of the different thickness steel sheet that is the material to be corrected, the longitudinal position information of the steel sheet is the steel material. It is judged from the plate speed and time.

  However, in reality, it is not intentional or unintentional to rely on order information to control the shape of the material to be straightened and the constriction conditions associated with it, regardless of the actual shape information. If the normal shape is not realized, it is not preferable because it may lead to troubles such as damage to the apparatus and deformation of the steel plate.

  An object of the present invention is to provide an automatic correction method for a differential thickness steel sheet that enables automatic determination of the longitudinal position of the steel sheet and automatic operation of a correction machine in the correction work of the differential thickness steel sheet using a roller leveler.

  The present invention has been made to solve the above problems, and the gist thereof is as follows.

  1st invention calculates the flatness of a difference thickness steel plate based on the information from a plate thickness measurement means and a steel plate movement distance measurement means, a plate thickness, and a movement distance, and determines a difference thickness boundary from the calculation result. An automatic correction control method for a differential thickness steel sheet, comprising: a step; and a step of changing a correction reduction amount from the determination result.

  According to a second aspect of the present invention, there is provided a differential thickness steel plate, comprising: a plate thickness measuring unit, a steel plate moving distance measuring unit, a steel plate shape processing unit, a differential thickness boundary determining unit, and a correction reduction amount setting unit. It is an automatic correction control device.

  3rd invention is a manufacturing method of the difference thickness steel plate characterized by correcting a difference thickness steel plate by the straightening reduction amount computed using the automatic correction control method of the difference thickness steel plate described in 1st invention. .

  ADVANTAGE OF THE INVENTION According to this invention, it became possible to perform the automatic correction operation | work of the difference thickness steel plate by a roller leveler, and came to aim at the productivity improvement of the correction operation of a difference thickness steel plate.

  The best mode for carrying out the present invention will be described in detail with reference to the drawings. In the following, the case of correcting a difference thickness steel plate having two types of flat portion plate thickness in the longitudinal direction of the steel plate will be described, but the object of the present invention is not limited to this, but three or more types of flat portions The present invention can also be applied to a differential thickness steel plate having a plate thickness.

  FIG. 1 shows a double-sided differential thickness steel plate 6 (hereinafter referred to as a differential thickness steel plate) having a flat portion having two types of plate thickness in the longitudinal direction of the steel plate and a tapered portion (hereinafter referred to as a differential thickness boundary) sandwiched between both flat portions. ) Is a diagram showing a configuration of the entire straightening device for the differential thickness steel plate 6 and further explaining a positional relationship on the line between the roller leveler 7 and the measuring instruments 1 and 2. . The differential thickness steel plate 6 is conveyed on the table roller 10 in the arrow direction 11.

  1 is a plate thickness meter that also serves as a flatness meter, and laser distance meters are installed at a constant pitch parallel to the table roller 10 in the width direction of the differential thickness steel plate.

  No. 2 measures the moving distance in the longitudinal direction (rolling direction) of the steel sheet after catching the tip of the differential thickness steel sheet 6 by the steel sheet moving distance measuring means, and performs tracking of the steel sheet based on this measured value. Usually, a laser Doppler velocimeter which is a non-contact type measuring instrument is used, but a measuring roll may be used.

  3 is a steel plate shape information processing device that calculates the flatness, plate thickness, and moving distance of the difference thickness steel plate based on information from the plate thickness meter 1 and the steel plate movement distance measuring means 2, and determines the difference thickness boundary based on this result. The information is sent to the correction reduction amount setting device 4.

  4 is a straightening reduction amount setting device, which determines specific operation amounts of the upper roll 8 and the lower roll 9 of the roller leveler 7 based on the information sent from the steel plate shape information processing device 3, and the straightening reduction amount information 5 is a roller. Sent to leveler 7.

  7 is a roller leveler, the upper roll 8 and the lower roll 9 are arranged in a staggered manner, and the amount of reduction changes by controlling the interval between the upper and lower rolls to correct the differential thickness steel sheet.

  FIG. 2 shows a state in which the plate thickness of the differential thickness steel plate (hereinafter referred to as the thick side) is corrected by the upper roll 8 and the lower roll 9 of the roller leveler 7.

  FIG. 3 shows a state where the sheet thickness of the difference thickness steel sheet passing through the difference thickness boundary (hereinafter referred to as the “thin side”) is corrected by the upper roll 8 and the lower roll 9 of the roller leveler 7.

FIG. 4 is an image diagram of the flatness of the surface portion of the differential thickness steel plate displayed by a flatness meter, where W indicates the width direction of the differential thickness steel plate and l indicates the length direction of the differential thickness steel plate. W _{1 to} W _n indicate the measurement positions of the laser rangefinder, the length direction l ₁ part is the thickness side of the differential thickness steel plate, l ₂ part is the difference thickness boundary from the thick side to the thin side, l ₃ part is Represents the thin side of a differential steel plate.

FIG. 5 is an image diagram showing the plate thickness of the differential thickness steel plate similarly measured by a plate thickness meter. The differential thickness steel plate length direction l ₁ part represents the thick side plate thickness t ₁ , and the l ₃ part represents the thin side plate thickness t ₃ .
It is possible to automatically correct the difference thickness steel sheet by capturing the position of the difference thickness boundary l ₂ from the information of FIGS. 4 and 5 and automatically changing the distance between the upper roll 8 and the lower roll 9 of the roller leveler 7. It becomes.

  Next, a control method will be described based on the flowchart of FIG.

  First, the tip of the steel plate on the inlet side of the difference thickness steel plate is caught (step 1: S1 in the figure), and the surface of the difference thickness steel plate is measured by the laser distance meter 1 and the laser Doppler velocimeter 2 installed in the width direction of the difference thickness steel plate. The movement distance of the shape, the plate thickness, and the differential thickness steel plate is measured, and the information is stored in the steel plate shape information processing apparatus 3 (step 2: S2 in the figure). Then, a difference thickness boundary is detected from the accumulated information (step 3: S3 in the figure). If the difference thickness boundary is not detected, the measurement in step 2 is continued.

When the differential thickness boundary is detected, the type of the differential thickness boundary is determined (step 4: S4 in the figure).
The type means a boundary where the reduction setting is changed from the thick side correction to the thin side correction or a boundary where the reduction setting is changed from the thin side correction to the thick side correction.

  This can be dealt with by continuously changing the reduction setting when the reduction setting changes from the thick side to the thin side, but tracking is required when shifting from thin side correction to thick side correction. This is because if the accuracy is poor, there is a risk that the thick side will be pulled in with the reduction setting on the thin side, so care must be taken. In this case, a distance timer may be used together as a safety measure.

  If the difference thickness boundary type is a boundary from the thick side to the thin side, the correction work is continued by changing the correction reduction amount (step 5: S5 in the figure).

  When the difference thickness boundary type is a boundary from the thin side to the thick side, the correction work is temporarily stopped and the correction reduction amount is released for safety measures of the correction machine (step 6: S6 in the figure). Then, the thickening correction reduction amount is reset and the correction work is continued (step 7: S7 in the figure).

  The example which implemented the correction method of the difference thickness steel plate in this invention on the following conditions is shown.

Roller leveler specifications Roller dimensions: Upper roller diameter 280mm, Lower roller diameter 280mm, Body length 4850mm
Number of rollers: Upper 4, Lower 5, Roller arrangement: Staggered Target material (Double-sided difference thickness steel plate)
Board width: 4400mm, board length: 26000mm
Thick part plate thickness: 25mm, Thick part length: 10000mm, Difference thickness boundary length: About 10mm
Thin plate thickness: 20mm, thin plate length: 16000mm
The above-mentioned difference thickness steel plate was inserted into the straightening machine from the thick part, and the straightening operation was carried out at a plate passing speed of 30 mpm. The sheet passing speed was tracked by using the reference sensor 3, and correction work was performed by automatically changing the rolling setting of the roller leveler 7 at the difference thickness boundary ( ₁₂ parts) of the difference thickness steel plate.

  By using the correction method of the present invention, the correction reduction amount resetting at the difference thickness boundary portion can be automated, so that the target material is compared with the case of using the conventional correction method of manually resetting the correction reduction amount. The correction work time was reduced by about 20%.

It is a figure which shows the structure of the whole correction apparatus of a difference thickness steel plate. It is a figure which shows the state which is correcting the thickness side of a difference thickness steel plate. It is a figure which shows the state which is correcting the thin side of a difference thickness steel plate. It is a flatness image figure of the difference thickness steel plate surface part displayed with a flatness meter. It is an image figure which shows the plate | board thickness of a difference thickness steel plate. It is a flowchart explaining a control method.

Explanation of symbols

1 Thickness gauge (also serves as a flatness meter)
2 Steel plate movement distance measuring means 3 Steel plate shape information processing device 4 Straightening reduction amount setting device 5 Straightening reduction amount information 6 Differential thickness steel plate 7 Roller leveler 8 Upper roller 9 Lower roller

Claims (2)

  Calculating a flatness, a plate thickness and a moving distance of the difference thickness steel plate based on information from the plate thickness measurement means and the steel plate movement distance measurement means; determining a difference thickness boundary from the calculation result; and the determination result. However, if the differential thickness boundary type is a boundary from the thick side to the thin side, the correction work is continued by changing the correction reduction amount, and the differential thickness boundary type is a boundary from the thin side to the thick side Comprises the steps of temporarily stopping the straightening operation, releasing the straightening reduction amount, then resetting the straightening reduction amount on the thick side and continuing the straightening operation. Correction control method.   A method for producing a differential thickness steel sheet, comprising: correcting the differential thickness steel sheet by a correction reduction amount calculated using the automatic correction control method for a differential thickness steel sheet according to claim 1.

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