JP5817473B2 - Method for calculating the remaining coil length on the process line - Google Patents

Description

  The present invention relates to a process line (for example, a pickling line, a rolling line, an annealing line, a surface treatment line, etc., which is a production line of steel products) having a coil delivery facility on the entry side, and in particular, a coil of the coil delivery facility. The present invention relates to a method for calculating the remaining length.

  In process lines (pickling line, rolling line, annealing line, surface treatment line, etc.) that have coil payout equipment (payoff reel, etc.) on the entry side, the remaining coil length of the coil payout equipment (payoff reel, etc.) is calculated. When the remaining length reaches a preset length, automatic deceleration of the entry line is performed to shear cut the tail end of the coil, and then the tail end of the coil and the tip of the succeeding coil Stop the entry line to perform welding.

  The most common method for calculating the remaining coil length on the entry side of the process line is the number of rotations of the payoff reel from which the coil (steel strip) is discharged and a predetermined roll (for example, input) through which the discharged steel strip passes. The present coil diameter is obtained from the rotational speed of the side bridle roll) and the roll diameter, and the remaining coil length is calculated from the coil inner diameter and steel strip thickness that are known in advance.

  However, with this conventional method, an error occurs in the calculation of the remaining length of the coil when off-gauge portions having different plate thicknesses are involved in the coil or when the plate thickness information is incorrect.

  Therefore, as a countermeasure, there is a method in which the plate thickness is regarded as a variable, the plate thickness is obtained from a change in the outer diameter of the coil for each predetermined rotation speed of the payoff reel, and the remaining coil length is calculated.

  However, with this method, the winding tightening at the time of coil discharge immediately before the start of automatic deceleration of the incoming line (when the state where the coil is discharged without the payoff reel rotating locally is recognized) Is generated, the calculated coil diameter is increased, and the plate thickness is reduced accordingly, resulting in an error in the calculation of the remaining coil length.

  As a result, if the remaining coil length has an error on the minus side (when the actual remaining length is shorter than the calculated remaining length), there is a problem that the bottom end will occur. Conversely, the remaining coil length is on the plus side. When an error occurs in the case (when the actual remaining length is longer than the calculated remaining length), there is a problem that the steel strip tail end is often cut off.

  Up to now, several techniques related to the calculation of the remaining coil length on the input side, the automatic deceleration method on the input side, and the control method have been presented (for example, Patent Documents 1 to 4). There is nothing to do.

Japanese Patent Laid-Open No. 4-94812 JP 7-88550 A JP-A-8-90060 Japanese Patent Laid-Open No. 9-262621

  The present invention has been made in view of the above circumstances, and in a process line having a coil payout equipment (payoff reel, etc.) on the entry side, the remaining coil length of the coil payout equipment (payoff reel) can be accurately determined. An object of the present invention is to provide a method for calculating a remaining coil length on the input side that can be calculated.

  In order to solve the above problems, the present invention has the following features.

  [1] A method of calculating a coil remaining length of the payoff reel in a process line including a payoff reel that pays out a coil and a bridle roll that conveys a metal band paid out from the payoff reel on the entry side, For each predetermined number of rotations of the payoff reel, the outer diameter of the coil paid out by the payoff reel is calculated from the rotation number and outer diameter of the bridle roll, and the coil thickness is calculated from the change in the calculated outer diameter of the coil. Based on the calculation method of calculating and calculating the remaining coil length of the payoff reel using the calculated outer diameter and thickness of the coil and the inner diameter information of the coil obtained in advance, the outer diameter due to winding tightening A calculation method for calculating the remaining coil length by replacing the plate thickness with the previous calculation plate thickness when a plate thickness calculation error occurs due to an error in the calculation result, and the process processor In combination with the calculation method for calculating the remaining coil length using the sheet thickness results in the previous process, compare the calculated remaining coil length by each calculation method and adopt the shorter calculated remaining coil length. A method for calculating the remaining coil length on the process line.

  In the present invention, the remaining coil length of the coil payout equipment (payoff reel) can be accurately calculated in the steel process line having the coil payout equipment (payoff reel, bridle roll) on the entry side.

  That is, it is possible to minimize the calculation error of the remaining coil length that occurs when the payoff reel is tightened, and the tail end trouble (the coil tail end passes through the welder before the automatic deceleration on the input side starts and the line stops) Trouble). In the past, the coil remaining length setting value (the coil length remaining on the payoff reel upon completion of the automatic deceleration on the input side) was set large (for example, 20 m) in order to avoid the bottom-out trouble due to winding tightening. On the other hand, the coil remaining length setting value can be shortened (for example, 8 m), which can greatly contribute to the reduction of the cut-off length of the coil tail end and the yield improvement.

It is a figure showing coil discharge equipment (pay-off reel, bridle roll) in one embodiment of the present invention. It is a figure which shows the comparison result of the example of this invention and the prior art example in the Example of this invention.

  An embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows a coil payout equipment according to an embodiment of the present invention. The coil payout equipment includes a payoff reel 3 for paying out the coil 1 while applying tension to the coil 1 (steel strip 2), and a payout. A bridle roll 4 is provided to convey the steel strip 2 at a speed.

Then, in this embodiment, when calculating the coil 1 remaining length of the payoff reel 3 (remaining number of turns), every 0.5 rotation of the payoff reel 3, the rotational speed r _BR and the outer diameter D _BR of bridle rolls 4 The outer diameter D _POR (m) of the coil 1 paid out by the payoff reel 3 is calculated by the following equation (1), and the calculated change in the outer diameter D _POR (n) of the coil is performed every five rotations of the payoff reel 3. The plate thickness t (n) of the coil 1 is calculated from (D _POR (n−1) −D _POR (n)) by the following equation (2), and the calculated outer diameter D _POR (n) of the coil 1 and the plate Based on the calculation method of calculating the number of remaining payoff reels (coil remaining length) NL (n) from the thickness t (n) and the inner diameter D _{PORO of the} coil obtained in advance by the following equation (3), winding tightening occurs Of outer diameter calculation result by Calculation method for calculating the remaining winding number (coil remaining length) NL (n) by replacing the plate thickness t (n) with the previous calculation plate thickness t (n-1) when a plate thickness calculation error occurs due to an error. And the calculation method of calculating the remaining coil length NL (n) using the sheet thickness actual tm in the previous process of the process line, and comparing the calculated remaining coil lengths by the respective calculation methods, the shorter one The calculated remaining coil length is an arbitrary set remaining length with a calculated coil remaining length (in this embodiment, for example, the remaining length setting + the length that the payoff reel pays out before completion of automatic deceleration (changes depending on the line speed)) +20 m), the number of rotations at which entry side automatic deceleration starts is determined.

  Further, as described above, the reason for adopting the shorter calculation remaining length is to prevent a trouble of line stop due to missing the bottom.

Regarding the occurrence of winding tightening, when it is recognized that the coil is paid out without locally rotating the payoff reel, the operator (operator) determines that the winding is tightened.
When it is determined that winding has occurred, the remaining coil length is calculated as described above.

D _POR (m) = 2D _BR xr _BR (1)
t (n) = (D _POR (n−1) −D _POR (n)) / (2 × 5) (2)
NL (n) = (D _POR (n) −D _PORO ) / (2 × t (n)) (3)

Thus, in this embodiment, the predetermined rotational speed for each of the payoff reels 3 (0.5 revolutions per), the outer diameter D of the coil 1 to be paid by the pay-off reel 3 from rotating speed r _BR of bridle rolls 4 _POR (m) is calculated, the plate thickness t (n) is calculated from the change in the outer diameter D _POR (n) of the coil 1, and the remaining coil number in the payoff reel 3 from the coil inner diameter information D _PORO obtained in advance. (Remaining length) When calculating NL (n), the consistency of the calculated thickness t (n) can be confirmed (abnormal data at the time of winding tightening can be removed). Even when tightening occurs when the coil 1 is discharged from the reel 3, the remaining length calculation error can be minimized, so that the remaining length setting can be shortened to the minimum.

  It should be noted that there is no problem even if the following formulas (4) to (6) are used instead of the calculation formulas (1) to (3) used in the embodiment of the present invention.

D _POR (m) = (1 / A) D _BR × r _BR (4)
t (n) = (D _POR (n−1) −D _POR (n)) / (2 × B) (5)
NL (n) = (D _POR (n) −D _PORO ) / (2 × t (n)) (6)
Here, A and B indicate the number of rotations of the payoff reel.

  Moreover, in said embodiment, although the coil of steel strip is made into object, this invention is applicable similarly to the coil of other metal strips.

  As an embodiment of the present invention, the remaining coil length calculation of the payoff reel 3 was performed in the coil payout equipment shown in FIG. Note that the target material was only a low-plate surface roughness material that was easily wound.

  At that time, as an example of the present invention, the remaining coil length calculation of the payoff reel 3 was performed based on the above-described embodiment of the present invention. On the other hand, as a conventional example, the remaining coil length was calculated based on the above-described method of calculating the remaining coil length by obtaining the plate thickness from the change in the outer diameter of the coil for each predetermined number of rotations of the payoff reel 3. The above equations (1) to (3) were used for the calculation of the remaining coil length.

  As a comparison result between the present invention example and the conventional example, FIG. 2 shows a histogram of the actual coil remaining length when the coil remaining length setting value is 18 m.

  As shown in FIG. 2, the average value of the actual coil remaining length was 16.15 m in the conventional example, but improved to 17.75 m in the present invention example. In addition, the data variation σ was improved to 1.34 m in the present invention example compared to 5.03 m in the conventional example.

  As a result, the coil remaining length setting value, which was set to 20 m in the conventional example in order to avoid the tail loss trouble, can be changed to 8 m in the present invention example, and accordingly, the coil tail on the entry side can be changed. We were able to reduce the amount of truncation at the edges.

1 Coil 2 Steel strip 3 Payoff reel 4 Bridle roll

Claims (1)

A method of calculating a coil remaining length of the payoff reel in a process line comprising a payoff reel for paying out a coil and a bridle roll for transporting a metal strip paid out from the payoff reel on the entry side, the payoff reel The outer diameter of the coil to be paid out by the payoff reel is calculated from the rotational speed and outer diameter of the bridle roll at every predetermined number of rotations, and the calculated change in the outer diameter of the coil every time the calculation is performed a predetermined number of times. Based on the calculation method of calculating the coil remaining length of the payoff reel using the calculated outer diameter and thickness of the coil and the inner diameter information of the coil obtained in advance, If the plate thickness calculation error by the error of the outer diameter of the operation result by the tightening occurrence had occurred, and the outer diameter of the plate thickness and the coil last calculated thickness and previously calculated A calculation method for calculating the coil remaining length by replacing the outer diameter of yl, used together with a calculation method for calculating the coil remaining length with an outer diameter of coils thickness actual and previously calculated in the previous step of the process line Then, the calculated remaining coil lengths by the respective calculation methods are compared, and the shorter calculated remaining coil length is adopted, and the incoming coil remaining length calculating method in the process line is characterized.

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