JPS5970420A - Method for tracking rolling material - Google Patents

Abstract

PURPOSE:To improve tracking accuracy, by calculating the coil diam. of a rolling material coiled by a mandrel basing on the condition at the time when the tail end of the material runs out from a final rolling stand, and changing a preset value basing on the calculated value at every time till the coiling is finished. CONSTITUTION:An output signal of a pulse oscillator 2 is inputted to a preset counter 7 and a speed counter 15, and a controlling pitch and a roll speed are inputted to a tracking controlling device 14, for a period from the time the front end of a rolling material 3 is bitten by a mandrel 6 to the time the tail end of it runs out from a final rolling stand 1. Further, the thickness of material 3 is outputted from a thickness gauge 12 to the device 14. An output of a pulse generator 10, generating a pulse in accordance with the rotation of mandrel 6, is inputted to a preset counter 11 and a pulse counter 13, and the controlling pitch and the measured number of coilings of mandrel 6 are inputted to the device 14. The device 14 calculates a coiled coil diam. basing on these values to change a preset value at every presetting.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a hot rolling system equipped with a rough rolling mill, a finishing rolling mill, a cooling device, a mandrel, etc. This invention relates to a method for tracking rolled material necessary for controlling positional stopping, etc.

[Technical background of the invention]

Generally, in hot rolling systems, this coiling temperature control,
DDC (Dire Control) such as Automatic Thickness Control (AGC) is used to control the classification eye, mandrel tail end fixed position stop, etc.
Control based on length pitch is performed instead of control based on time pitch, which is performed in CT Digital Control. For this reason, tracking of the longitudinal direction of the rolled material is required.

Conventionally, when the final rolling stand 1'lC rolled material 3 shown in FIG. The control pitch is obtained through the preset counter 7, which is preset as the control pitch, and after the tail end of the rolled material passes through the final stand J, the pinch roll 4Vr-
The information was similarly obtained via the preset counter 8 by switching the attached Noculus oscillator 5. The control pitch thus obtained is input to the tracking control device 14, and a rolling control device (not shown) is controlled thereby.

[Problems with background technology]

However, since tension is applied between the pinch roll 4 and the mandrel 6 in order to improve the winding shape of the rolled material 3, a gap is created between the pinch roll 4 and the rolled material 3. On the other hand, the influence of back tension caused by the hot run table 9 also makes the surface between the pinch rolls 4 and the rolled material 3 non-uniform. Therefore, due to this phenomenon, the tracking accuracy of the rolled material 3 by the pinch rolls 4 is very poor and uneven), and therefore, the accuracy naturally deteriorates in various rolling controls based on these tigers and kings. was occurring.

For this reason, it is desirable to improve accuracy, and in particular, tracking after the rolled material passes the final stand requires coiling temperature control using a hot run spray, classification using a coiling thermometer and width gauge, and tail edge determination using a mandrel. There was a desire to improve the accuracy of position stops, etc.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for rolling a rolled material with improved precision.

[Summary of the invention]

In order to achieve the above object, the present invention calculates the diameter of the coil wound on the mandrel based on the speed of the rolled material, the thickness, and the number of windings on the mandrel when the tail end of the rolled material passes through the final rolling stand. However, based on this calculated value, a preset counter provided on the mandrel side is reset each time until the rolled material is completely wound on the mandrel.

[Embodiments of the invention]

Examples of the present invention will be described below.
An apparatus for carrying out the method of the present invention will be explained with reference to the figures. That is, a pulse oscillator JO is attached to the mandrel 6, which generates a noculus according to this rotation. The output of this pulse generator 10 is the preset counter 11
are input to the Noyals counter J3, the control pitch is output from the preset counter J1, and the actual number of windings of the mandrel is output from the pulse counter 13.

In addition, the output of the pulse transmitter 2 attached to the final rolling stand 1 is input not only to the preset counter 7 but also to the speed counter 15. The number of pulses is counted to measure the roll speed. The arm pulse transmitters 2 and 10 detect iJ? from when the head end of the rolled material is bitten by the final rolling stand 1 until the end of the rolled material passes through the tail end of the rolled material. Only the pulse transmitter 2 is driven, and when the tail end of the rolled material passes through the final rolling stand 1 from this state, only the pulse transmitter 10 is driven by a switching circuit (not shown).

Further, the instantaneous value of the thickness of the rolled material 3 is measured by the thickness gauge 12 from when the head end of the rolled material is bitten by the mandrel 6 until the tail end of the rolled material passes through the final rolling stand 1. The present invention differs from the conventional example described above only in the points described above.

The outputs of the preset counters 7, J1, the pulse counter 13, the speed counter 15, and the thickness gauge 12 are input to a tracking control device (hereinafter referred to as a control device) 14, where they are calculated as follows.

In addition, when the rolled material 3 is caught in the final rolling stand 1, the control pitch is the same as in the conventional example shown in FIG.
The output signal is obtained by the preset counter 7 which has been reset to control the number of parables of the pitch master.

The roll speed of the final rolling stand 1 from when the head end of the rolled material is bitten by the mandrel 6 until the tail end of the rolled material passes through the final rolling stand 1 is determined by A? Lux transmitter 2, speed counter 15 and multi-control device 14
is input into the controller 14, and the length of the rolled material wound by the Simandrel 6Vc is calculated using the following equation 0.

6-Here, tl: time when the head end of the rolled material bites the mandrel, t2: time when the tail end of the rolled material passes through the final rolling stand J, v, the final rolling stand roll speed determined by the speed counter 15, f: Advancement ratio of the final rolling stand roll.

Further, the output (instantaneous value) from the thickness meter 2 during this period is read into the control device 14 at a predetermined pitch, and the average value thereof is calculated within the control device 14. Comparing the side surface area of the rolled material before being wound on the mandrel 6 and the side surface area after being wound on the mandrel, the width and thickness of both rolled materials are the same, where h = measured thickness. The average value DM=diameter of the mandrel Dc=diameter of the winding coil, which is expressed by the formula 0.

DC=DM+2nh where n=mandrel winding number. According to the equations (2) and (2), the number of windings on the mandrel in the state shown in FIG.

Here, the actual number n' of windings on the mandrel when the tail end of the rolled material passes through the final rolling stand 1 is obtained from the roll counter 13. Therefore, taking into account errors due to minute separation between the winding surfaces, etc., and assuming the ratio n'/n t-k (constant) of the measured value n' of the number of windings to the calculated value n using formula 0, formula 0 is obtained. holds true.

n'=kn...
...■Also, after the rolled material 3 is removed from the final rolling stand 1,
In order to obtain a predetermined control pitch t, a preset value P for resetting the preset counter 11VCf on the mandrel 6 side can be obtained from formula 0.

Here, N = Noculus number generated in one rotation of the mandrel t=control pitch It is.

However, DCI is the diameter of the winding coil at the instant when the winding becomes thicker from time to time, and is a formula 0 derived from the formulas ■, ■, and ■. □ D' = D +2knh --
------- ■CM Next, the method for rolling and tying rolled materials according to the present invention will be explained.

From the time when the head end of the rolled material is bitten by the mandrel 6 until the tail end of the rolled material passes through the final rolling stand 1, the output signal of the pulse generator 2 presets the number of pulses corresponding to the control pitch. is input to the reset counter 7. The operation in this state is the same as in the conventional example described above.

On the other hand, in this state, the output of the speed counter 15 is input to the control device 14, and the length of the rolled material wound around the mandrel 6 is calculated based on Equation 0. Further, the thickness output (instantaneous value) of the rolled material 3 from the thickness gauge 12 is input to the control device 14 at the timing when the rolled material 3 passes through the final rolling stand 1, and the average value of the measured thickness is calculated. Further, at the timing when the rolled material 3 passes through the final rolling stand 1, the side value P is calculated according to the formulas (1), (2), and (2). When this series pitch value P is reset in the reset counter 11, the value set so far is cleared and an interrupt signal is output. The control pitch will be the same as the previously obtained control pitch.

And the preset counter 11 immediately after switching from the /4 Lus transmitter 2 to the A/Lus transmitter 10 on the mandrel 6 side.
When the control device 14 inputs the interrupt signal from , the control device 14 inputs the preset value L/ obtained by the formula reset.

10- At this time, L'=L+/ in the formula
are added and preset using the 0 formula. When the control pitch L is obtained at the final rolling stand J, the cypress value may remain unchanged as long as the roll diameter is not changed. However, when switching to the mandrel diameter side to obtain the control pitch t, the winding thickness increases as the coil diameter is wound, so it is necessary to change the preset value for each preset. .

Thus, embodiments of the method of the invention improve accuracy. This is for the following reasons. When the control pitch is obtained on the final rolling stand 1, there is no need to set a preset value unless the roll diameter is changed, but when switching to the mandrel 6 and obtaining the control pitch, the coil diameter changes. This is because the winding becomes thicker and larger as it is wound, so the preset value Pt is changed for each preset.

Specifically, the improvement in track and king accuracy according to the embodiment of the present invention is as shown in FIG. 4. In the conventional method of tracking A using pinch rolls 4, the length after the final rolling stand is taken as L3, and "# If the amounts of slips a, b, and c occur at point b'lL/, then d-
A length error of L4Ls=a+b+c has occurred.

Note that L3 is the length grasp point for control using the conventional method! +
, L4 is the actual length of the control according to the invention.

Furthermore, even if the control pitches up to 1 and 2 are synchronized with the tracking method B according to the present invention, after the first slip occurs, the synchronization is J', 13' for each point of the rolled material.
I get confused. Note that in FIG. 4, TAL indicates the tail end of the rolled material.

Furthermore, the present invention does not use the mandrel diameter as the initial value of the winding coil diameter in formula 0, but calculates the coil diameter at the moment of switching from the final stand to the mandrel as in formula 0, so there is an error due to the space factor setting error. It is possible to suppress the cumulative expansion of Furthermore, at the time of resetting, the constant used in equation 0 is determined from the theoretically calculated value n and the actually measured value n' of the number of windings, so it is not an assumed value and has almost no error.

As described above, the embodiment of the present invention relates to a method of tracking rolled material to obtain a constant length control pitch from the speed, thickness, and number of windings of the rolled material on the mandrel.
Speed and thickness can also be obtained by other methods. For example, as shown in FIG. 3, the length of the rolled material can be obtained using a pulse counter 16 inputting the output of the pulse generator 2 in the following manner.

n proverb L=-πD Song...■1 Here, n1 = number of pulses generated in one rotation of the final rolling stand roll, n3 = the number of pulses generated when the head end of the rolled material is turned on after the mandrel is turned on, and the tail end is This is the number of pulses counted by the pulse counter 16 while the final rolling stand 1 is turned off.

In addition, if the counting period of the speed counter 15 in Fig. 2 is set from the time when the head of the rolled material is bitten by the final rolling stand I13- until the tail of the rolled material comes off, the preset value at this time is Riha, L Engineering LI Lm song/song ■t1
' = Time when the head end of the rolled material bites the final rolling stand 1, t7 = Time when the tail end of the rolled material leaves the final rolling stand 1, τ = Final rolling stand roll speed 1 f = Final rolling stand roll advance rate, L2 = hot run table length (fixed), can be used as follows.

Furthermore, with regard to the thickness of the rolled material, it is also possible to use the target thickness, as long as the thickness accuracy can be achieved without using the actual measured value.

14- [Effects of the Invention] As described above, according to the present invention, accuracy is improved compared to conventional methods, and this directly improves the accuracy of various rolling controls and improves the quality of rolled products. We can provide you with a tiger, king way to tie.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining a conventional tracking method for rolled material, FIG. 2 is a diagram for explaining an embodiment of the tracking method for rolled material according to the present invention, and FIG. 3 is a diagram for explaining a rolled material according to the present invention. FIG. 4 is a diagram for explaining the operation and effect of the embodiment of FIG. 2. FIG. 1... Final stand, 2... Pulse transmitter attached to the final stand, 3... Rolled material, 4... Pinch roll, 5
...Pinch roll installation No. 4? Luss transmitter, 6... Mandrel, 9... Hot run table, 10... Man P V Le mounting no. 4 Luss transmitter, 11... Preset counter for mandrel pulse transmitter, 12... Thickness 1
Lis-Mandrelno 4 Lus transmitter Noculus counter, 14...Tracking control device, 15.16
...Speed and noggles counter for final rolling stump P-gusis transmitter, A...Conventional tracking method, B...Tracking method of the present invention, King method 1, /, b/
, C/, ・Slip occurrence point, a, b, c...
- Amount of slippage, d... a-1-b+c, I, 3... Length grasped for control by conventional method, L4... Length ζ for control by the present invention, actual length. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2, 12 3 4 Sheed 1
Ha0ru χ 7m Soeq Toka Quanter Counter Counter H Run Two 15 7 13 11 Tiger 7
Afternoon 2". Figure 3 Figure 4

Claims (1)

[Claims] In a device that winds the rolled material from the final rolling stand onto a mandrel, the speed of the rolled material when the tail end of the rolled material exits the final rolling stand, the thickness, and the number of windings on the mandrel are determined. The diameter of the winding coil to be wound on the mandrel is calculated, and the diameter of the winding coil is calculated on the mandrel side until the tail end of the rolled material passes through the final stand and winding of the rolled material on the mandrel is completed. A tracking method for rolled material in which a preset counter provided in the machine is preset each time.