Kabushiki Kaisha Toshiba

Tokyo Shibaura Denki Kabushiki Kaisha

Kawasaki Steel Corporation

Kunio Sekiguchi

Takumi Sato

Tomoyuki Tezuka

Yoshiro Seki

Toshihiro Koyama

Yosuke Tonami

Kenji Ueda

Hajime Kai

Youji Abiko

Takashi Chujo

Masaharu Noguti

Tomohiro Kanai

Masaru Miyokawa

Mamoru Sawada

A strip thickness control apparatus for a rolling mill includes a strip thickness gauge provided on a delivery side of the rolling mill, a moving distance calculating module for calculating a moving distance of the strip from the rolling mill, a rolling roll angle-of-rotation calculating module for calculating an angle of rotation of the rolling roll, a strip thickness deviation calculating module for calculating a deviation of the strip thickness from a target value of the measured value of the strip thickness, a strip thickness deviation storage module for storing the strip thickness deviation by adding it for every angle of rotation of the rolling roll, a strip thickness deviation input determining module for determining an input timing for inputting the strip thickness deviation to the strip, thickness deviation storage, a strip thickness deviation output determining module for determining an output timing for outputting the strip thickness deviation stored in the strip thickness deviation storage module, and a manipulated variable calculating module for fetching the strip thickness deviation at the output timing determined and determining a manipulated variable of a roll gap controller.

Strip thickness control apparatus for rolling mill

A strip thickness controller for a rolling mill, which is capable of reducing a delivery-side strip thickness deviation due to an eccentricity of a backup roll even in a rolling mill incapable of easily performing a kiss-roll. The strip thickness controller provides with a thickness gauge, provided in a position spaced a distance shorter than a circumference of each of backup rolls on a delivery side of the mill, for detecting a strip thickness deviation from a set value, an angle detecting unit for outputting a rotational angle detection signal at every equally-segmented portion when an angle of one rotation of the backup roll is, with &ldquo;n&rdquo; being a positive integer, segmented equally by &ldquo;n&rdquo;, a calculating unit for calculating a forward slip of the mill at a point of time when a first rotational angle detection signals outputted, and calculating, based on the forward slip and the circumference of the backup roll, a delivery-side strip length of the rolling mill which corresponds to one rotation of the backup roll and a delaying unit for delaying a strip thickness deviation signal of the thickness gauge by a strip transfer time corresponding to a difference between the delivery-side strip length calculated by the calculating unit and a distance of the thickness gauge from the rolling mill.

Strip thickness controller for rolling mill

Continuous rolling is conducted by interposing loopers respectively between a plurality of successive stands and connecting a rear end of a preceding bar to a top end of a next bar. Roll gaps of the respective stands are each controlled by thickness control units. Interstand mass flow variations are each controlled by mass flow control units. Looper heights are controlled by looper height control units. Further, interstand tensions are controlled by looper tension control units. If no looper is provided, the interstand tensions are controlled by looperless control units. A flying thickness change control unit tracks a connecting point. The flying thickness change control unit switches over looper tension control and looperless control and changes a reference tension and a reference looper angle so that tensile and flexural forces are not applied to this connecting point.

Method of controlling a hot strip finishing mill

There is disclosed a looper control system for a continuous rolling mill comprising: a section for performing the integral operation of respective deviations between measured values and target values with respect to the tension and the looper angle, and the proportional operation of respective deviations between the tension, the looper operation angle, and the rotational speed of the looper motor at the time of start of the control and those at the present time to synthesize values thus obtained to deliver them to the looper current control unit or the looper control unit, a section for performing the integral operation and the proportional operation similar to the above to synthesize the values thus obtained to deliver them to the main motor speed control unit; and an optimum gain setting unit for correcting respective proportional gains in dependency upon the speed of the main motor. The system may additionally have a section for altering the optimum gain by the fact that the tension is extreme and/or the looper angle is extreme.

Looper control system for continuous rolling mill

A rolling load signal is detected during a few rotations of a top and a bottom backup roll at different detection time points at which the top and bottom backup rolls are out of phase from each other and then are analyzed by Fourier analysis so as to detect the amplitudes and phases of the eccentricity of the top and bottom backup rolls separately, whereby the roll gap is controlled and the separately detected eccentricity of the top and bottom backup rolls is thus obtained. Even when there is a difference in roll eccentricity frequency between the top and bottom backup rolls and even when external disturbances exist due to the aging of the roll eccentricity and to the estimated errors of the mill constant M and the plasticity coefficient Q of a piece of metal to be rolled, the roll eccentricity can be suitably adjusted so that the roll eccentricity can be detected with a high degree of accuracy and then eliminated.

Method of controlling elimination of roll eccentricity in rolling mill

In a load current detecting apparatus of a DC motor for driving a mill stand and utilized to maintain a predetermined interstand tension, a simulating circuit is provided to remove the effect of acceleration or deceleration current and moment of inertia of the motor.

Load current detecting apparatus of direct current motors

A method of controlling a tandem rolling mill so as to minimize strip tension variations when the pass schedule is being changed. This result is achieved by selectively changing the roll speeds of the stands and the roll openings by means of an electronic computer.

Method of controlling tandem rolling mills

In a method of controlling the roll gap of a cold rolling mill of the class wherein the rolling load is first estimated and then the roll gap is calculated, the deformation resistance of the material being rolled is determined in accordance with a constant determined by the reduction, the strain rate, and the temperature and quality of the strip being rolled; the exit strip temperature is determined by taking into consideration the reduction and the characteristics of the rolling mill; the mean deformation resistance of the strip is determined from the deformation resistance and the exit strip temperature; the rolling pressure is calculated in accordance with the equation as hereinbelow defined for determining the rolling pressure by using the mean deformation resistance; and then the roll gap is determined and controlled in accordance with the equation of a gauge meter as hereinbelow defined.

Growing community of inventors

Kawagoe, Japan

Kunio Sekiguchi