DE2110539A1 - Method and device for controlling a continuous tandem rolling mill - Google Patents

Description

Patent attorney patent attorneys

Dr. phil. Gerhard Henkel ^Dr - ^ΓΘΓ · ⁿ ^ · Wolf-Dieter Henkel

757 Baden-Baden Bellow Dl pi.-Ing. Ralf M. Kern

waidgasse 20 8 Munich 90

Τ · Ι .: (07221) 63427 Eduard-Sdunld-Str. 2

Talegr.-A *: Elllpwld Bcctai-tedM Tel .: (0811) 225197 T «l« gr.-Adr.s EUIptoM KNmJm *

Γ Π

From 9/16/70 new phone number 66 31 97

ITl_jpori Kol: to Kabushiki Kaisha
Tokyo, Japan

L j · I & WU- ^

Urmt Ζ · Μμ «:

"Method and device for regulating a continuous

Tandem rolling mill

The invention relates to a method for controlling a Rolling mill and in particular a method and a device for controlling a continuous tandem rolling mill, with the help of which the rolling plan during operation at high rolling speed for the production of products different thickness can be varied.

When carrying out the so-called step-wise rolling, i. E. in the production of metal strips or bands different thickness on both halves of the entire length of the tape, it was previously common for the operator after stopping the rolling mill or after reducing the rolling speed to a very low fourth Changed thickness setting by hand. In modern continuous rolling mills, this becomes the front in the direction of movement End of a subsequent band is welded to the rear end of a previous band to form a continuous roll out very long tape. In such a continuous rolling mill, the rolling plan or the product thickness varied during the rolling process.

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POSTAL CENTER: 8 Munich 90, Eduard-Schmld-Str. 2

For the operation of the continuous rolling mill with the highest In terms of efficiency, it is essential that the rolling mill operation is not interrupted and that the rolling mill is not interrupted at the highest possible rolling speed is operated. Therefore, if the thickness of the starting strip or the finish-rolled product is through If the roll gap is to be changed, this must be done, if possible, while the rolling speed of the whale mill is increasing is kept as high as possible »

^ If the thickness is changed at high rolling speed however, even a small change in thickness or the timing of the change in thickness causes a large deviation the strip tension, which not only results in a large proportion of finished rolled products with different thicknesses is produced, but also a rupture of the ligament can occur.

In addition, when rolling out in stages, it is highly desirable to keep the strip thickness below. High rolling speed operating conditions and under conditions to reduce the variation in strip tension to vary the rolling efficiency increase and reduce the risk of a ligament rupture "

W To this end, the thickness change at the individual waiz _o must erüsten done in the correct timing.

The object of the invention is therefore primarily to create a novel control method and a device for a continuous tandem rolling mill, wherein the thickness of the strips to be rolled out while the rolling mill is at high rolling speed works, can change, without the need for a reduction in the rolling speed or a Shutting down the rolling mill.

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Another aim of the invention is to create a new one Method and a novel device for regulation a continuous tandem rolling mill, whereby the thickness of the rolled strip can be varied without impermissible Cause fluctuations in tape tension, thereby preventing tape breakage.

Yet another object of the invention is to provide an improved method and apparatus for simply changing the thickness of a continuously moving rolled strip or strip by means of a one-man control.

These tasks are in a procedure for the regulation of a Tandeui-Walsuerks, with polygamy; the strip thickness is changed during the rolling process ₀ s, according to the invention, in that a counting process of the number of signal pulses from a pulse generator assigned to a deflecting orphan on the entry side of several rolling mill stands is initiated as a function of a signal generated by a thickness change point detector, which is sent to the The entry side of the various rolling stands is arranged and the passage of the thickness change point on the rolled 3and determines, then the first roll stand,. Assuming that the thickness change point has reached this, is set to a predetermined rolling schedule, if the Number of counted signals has reached a certain value, at the same time that the counting of the number of pulse generators generated by one of the roll of the first stand is initiated, the second four-roll stand is set to the predetermined rolling schedule when the counted number of pulses of the Finally _{, the} pulse generator reaches a predetermined value, and the same setting processes are repeated for the following stands until the last stand is set to the rolling plan that is correct.

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BAD ORIOINAL

To carry out this method, the invention creates a device for regulating a continuous tandem rolling mill with a plurality of spaced apart rolling stands and a deflection roll on the inlet side of the rolling mill, this device being characterized by a thickness change point detector which is designed so that it has a thickness Knderungspunkt on the B _a nd discovered and which provides in response a signal pulse, one of the number of deflector rolls and the roll stands corresponding number of pulse counters, a plurality of pulse generators, each of which is associated with the deflector roll and the work rolls of the rolling mill stands and signal pulses to the respective counter, means for transmitting the output pulse from the thickness change point detector to one of the counters which receives the output pulse from one of the pulse generators associated with the deflection roller, means for applying the output signal of each preceding Ehenden counter to each downstream counter, a correction computer for presetting a predetermined value of the counted number of signal pulses in each of the counters and a plan setpoint signal generator, which is able to receive the output signal from the counters concerned to preset rolling plans for the individual roll stands transfer.

In a preferred embodiment yet to be described, has a device for changing the rolling thickness during the operation of a tandem mill without interrupting its Functioning a detector for the thickness change point, pulse counter and a plan setpoint signal generator.

If a weld seam of the band as a thickness change point is used, the detector can be a device that, depending on this weld seam, generates a signal

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pulse supplies; if, on the other hand, no weld seam is available as a thickness change point, it can be preset in this way be that he has a predetermined length of tape or a predetermined number of turns of the unwound from a coil Bands corresponds. In the latter case, a predetermined A signal representing the length can be generated by a signal transmitter connected to the unwinding roller or a deflection roller connected is.

Optionally, a perforation or a notch or an optical, a magnetic or a radioactive marking can be provided, which is caused by a photoelectric Detector, a latitude detector, a magnetic detector or a radiation detector detected to generate a signal representing the thickness change point.

To improve the reliability of the determination, two or more detector systems of different types can be combined with each other. Furthermore, a manually operated pressure switch can be used to support the automatic system be used.

During the interval between the moment in soak in a signal is generated by the thickness change point detector, and the moment in which the thickness change point is softened reaches the first stand, it is assumed that the length of the strip on the entry side of the first stand is between the latter and the thickness change point the orsto framework runs through and that the plan setpoint transmitter transmits the setpoint to the first stand to the next rolling speed to adjust to a different thickness.

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If, then it is assumed that those between the first and The length of the strip existing on the second stand pass through the rolling mill and consequently the thickness change point is the second Has reached the stand, the plan setpoint signal generator sends the setpoint signal relating to the second stand during of the rolling schedule for the next thickness.

During the thickness change point the last rolling mill stand reached, the signal generator sends in a similar manner the target value signal relating to the last stand during the rolling schedule for the next thickness.

The passage of the thickness change point from one scaffold to the next can be done by counting the number sent by a pulse generator Signal impulses are determined, which is based on the multitude of one Roller is mounted and emits a number of pulses corresponding to the length of the belt between adjacent ones. Rolling mill stands. If the dar stripe length between adjacent Scaffolding corresponding number of. Impulses generally dependency of the roll diameter and the forward slippage must a correction according to the following equation

<jf R (1 + f)

be made, in which 1 the distance or the strip length between adjacent rolling mill stands, R the roll diameter, IJ is the number produced per revolution of the VJaIze Impulses, f the forward slip and k the number of impulses corresponding to the distance between the stands.

The following is DIE iii fiiidung based on the Zexminung closer he explained that v ^ iiie partially scheniatische representation for United deutlichung dos erfiadun ^ february _o ei: iä3en ftegolverfahrens illustrated. ■ "- 7 -

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BAD OhiüiNAL.

_ rr _

The figure illustrates a preferred embodiment of the control device according to the invention in use a five-stand rolling mill.

A detector 1 detecting the Dieicen change point supplies a signal pulse to a pulse counter PC 1, when the dieken change point passes it, pulse generators 9, 10, 11, 12 and 13 are each on a deflector roller

2 on the entry side of the roll stand in question as well as on the drive shafts, the work rolls of the respective stands

3 to 7 and deliver pulses corresponding to the number of revolutions of the deflection roller and the work roller to counters PC1, PC2, PCJ, PC4 and PC5, respectively 1-j Il ^ / St Rd expressed fourth preset, where 1. the distance between the detector 1 for the thickness change point and the first stand 3, Nj the number of pulses per revolution of the deflection roller 2 and Rd the diameter of the deflection roller.

In addition, the correction calculator stores a _{value expressed by the equation k = I n} N _n / KR _n (I + f _n ) in one of the counters PC2 to PC5, where 1 is the distance between adjacent rolling mill stands, N _{n is} the number of Pulses per revolution of the work _{roll, R n} their diameter and f _n the "Forward-Sehlupf".

Upon receipt of a command signal for initiating the count of each counter starts counting the signal pulses generated by the associated pulse generator, and when the counter has counted a predetermined, preset by the correction calculator number of pulses, an output signal is provided. While the counter PC1 initiates its counting process as a function of the output pulse emitted by the detector for the thickness change point, the counters PC2 to PC5 are put into operation by the output signals emitted by the previous counters, which are generated when the preset number of pulses is counted down is. "· 8th -

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Furthermore, a plan setpoint signal generator 20 is provided in which the rolling plans of the respective VJalzgerestand for the next thickness are stored by an independent controller computer or a manual switch, not shown; these stored rolling plans become the control device as a function of the output signals of the relevant counters transferred for the respective roll stands.

After the end of a rolling process, the settings of the relevant counters and the plan setpoint signal generator are made modified for the next strip thickness.

In this way it is possible according to the invention, the thickness of the rolled strip during the operation of a continuous Rolling mill to vary at high speed without stopping the rolling mill or reducing the Rolling speed would be required and without risk of excessive fluctuations in the strip tension, so that the operating efficiency is increased.

According to the invention, it is thus not only possible to reduce the fluctuations in belt tension and belt tears to a minimum value reduce and keep the production of rolled products of differing thickness to a minimum, but also save labor costs, since the change in thickness can be made by one-man control.

Although the invention is in a preferred embodiment above As illustrated and described, numerous changes and modifications will of course be apparent to those skilled in the art possible without departing from the scope and concept of the invention.

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In summary, the invention thus provides a method and a device for changing the strip thickness while it is being rolled out at high speed in a continuous tandem rolling mill, the counting process being dependent on the number of signal pulses emitted by a pulse generator assigned to a deflection roll on the entry side of several rolling mill stands is initiated by a signal generated by a thickness change point detector located on the entry side of the rolling mill. The first roll stand is set to a predetermined rolling schedule when the number of signal pulses counted has reached a predetermined value, provided that the thickness change point reaches the first roll stand. At the same time, the counting process of the äs * ¹ number of pulses emitted by one of the pulse generators assigned to the roll of the first stand is initiated, while the second roll stand is set to the predetermined rolling schedule when the counted number of pulses emitted by the last-mentioned pulse generator exceeds the predetermined Value reached. Similar setting processes are repeated for the subsequent rolling stands until the last stand has been adjusted to the predetermined rolling schedule.

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Claims (1)

Patent to s ρ r ü ehe Method for controlling a tandem rolling mill, in which the strip thickness is adjusted during the rolling process is changed, characterized in that first a counting process of the number of signal pulses of a pulse generator assigned to a deflection roller on the inlet side of several rolling mill stands is initiated by a signal generated by a thickness change point detector, which is transmitted to the Entry side of the various roll stands is arranged and the passage of the thickness change point on the rolled strip, then the first stand, assuming that the thickness change point this has reached, is set on a predetermined rolling schedule when the number that counted Signals has reached a certain value, at the same time thus counting the number of from one of the The impulses generated by the roller of the erected frame are initiated, the second The rolling mill stand is set to the predetermined rolling schedule when the counted number of pulses of the last-mentioned pulse generator reaches a predetermined value, and similar setting operations for the subsequent stands are repeated until the last stand is set to the predetermined rolling plan. - 11 - 109841/1 U6 2. The method according to claim 1, characterized in that the predetermined value of the counted number of Signal pulses by the equation k - -IN . JTr (1 + f) it is determined in which 1 the distance between the neighboring roll stands, R derj. Diameter of the roller, N is the number of pulses generated per revolution of the roller and f is the forward slip. Method according to Claim 1, characterized in that the predetermined value is obtained with the aid of a correction computer fed into each meter, which are respectively assigned to the deflection roll and the work roll of the roll stands concerned. A method according to claim 1, characterized in that the thickness change point has the shape of a Weld seam between different tape cuts, a perforation, a Keioe or an optical, a magnetic or radiative mark formed on the edge of the tape. Device for performing the method according to a of claims 1 to 4, in particular for controlling a continuous tandem rolling mill with several spaced apart roll stands and a deflection roller on the inlet side of the rolling mill, characterized by a thickness change point - 12 1 09 8 Λ 1 / 1U6 Detector (1) which is arranged so that it has a thickness change point on the belt to generate a Signal pulse is able to determine several pulse counters (PC1 to PC5), the number of which is the sum of corresponds to the sum of the deflection roller and the number of roll stands (3 to 7), several each of the deflection roller (2) and the pulse generators (9 to Ό) assigned to the work rolls of the stands, several pulse generators, each of which feeds the output pulse from the detector to the counter, which receives the output pulse from the pulse generator, which is associated with the deflection roller, receives a device for feeding the Output of each previous counter into each subsequent counter, a correction computer (19) for presetting or storing a predetermined Number of signal pulses in each counter and a plan setpoint signal generator (20) which receives and predetermined the output signals from the relevant counters Supplies rolling plans for the respective roll stands. 6. Apparatus according to claim 5, characterized in that the predetermined value preset or stored by the correction computer (19) is given by the equation k ^1N JTR (1 + f) it is determined in which 1 the distance between adjacent whale frames, R the diameter of the roller, IT is the number of pulses generated per revolution of the orphan and f mean the forward slip. 1 0 9 8 U 1/1 US