how to control eccentricity problem in hot rolling mill

Finished steel pipe Cold drawn steel pipe can also cause eccentricity problems due to perforation: Any factor that destroys the geometrical correctness of the deformation zone formed by the roll, the head and the guide plate will increase the uneven thickness of …

To control the output thickness, the motion of hydraulic cylinder controlling the roll gap position is such that produces the desired output thickness [6]. Roll eccentricities are caused by axial...

The strip exit thickness h, is given by: h =S (F,W) + (S-So) + e (1) where S (F,W) is the elastic deformation of the stand components, W is the strip width, S is the rollgap position with respect to an arbitrary datum, So is a constant and e is the effective total eccentricity signal for the complete set of rolls in the mill.

In this article the AGC (Automated Gauge Control) system, of a hot rolling mill is analyzed and different methods are described to improve its performance. The mill stretch compensation and other disturbances during the rolling process are

A method of rolling material in a rolling mill in which the material is directed from an unwind coil of the material to the mill and/or to a rewind coil of the material from the mill, the material being under tension as it is directed to and from the mill. The directing process has at least one cyclic disturbance which ordinarily causes cyclic changes in the tension of the material and in the ...

Controlling the hydraulic automatic gauge control (HAGC) of cold reversible rolling mill is a significant engineering challenge ...,the unifiedgauge-tension control problem isformu- ... roll. In addition, the compensation for the roll eccentricity using the Fuzzy neural network with the in-line adjustment is proposed.

These strategies are well known and are described, for example, in "Automatic Shape Control-- Hoogoven's 88--In. Hot Strip Mill" by F. Hollander and A. G. Reinen, Iron and Steel Engineer, April, 1976. Strip flatness control will be improved where the rolling force at each stand is maintained more nearly constant throughout the strip length.

Definition of Rolling process: Rolling is defined as a process to form metals where the metal strip is pressed by two or multiple rollers, thus the uniform thickness is formed. To do this, the temperature is essential. There are two types of processes. One …

Rolling mill simulator A new platform for testing, analysis and optimization of cold rolling mills. Axel Brickwedde, Frank Feldmann, Nicolas Soler The cold rolling of flat metal products especially in tandem or multi-stand mills is a highly complex process where the product quality is influenced by various aspects.

nalprozessor, MA Thesis, Department of Automatic Control and Control Sys- tems Technology, Johannes Kepler University, Linz, Austria. 3. Aistleitner K., Kugi A., Manhartsgruber B. (1998) On-line identification of deformation resistance and mill stretch coefficient for …

an overview of the hot finisher mill after the upgrade, and describes the new control technology and hot rolling pro-cess control system that were introduced. 2. GENERAL DESCRIPTION The hot rolling mill of the Fukui Works went into service in May, 1983 as a world-class facility, equipped with large rolling stands capable of producing wide ...

The control of rolling is done by a machine, or rolling mill. From a control point of view it is necessary to study the combined behavior of machine and metal deformation to find the variables that may be used to most effectively regulate the process. A typical problem in this area is to control the output thick-

Different kinds of flat rolling mills exists, e.g. Sendzimer, Cluster, Steckel, 4-high, 5-high, 6-high, Z-high and Planetary mills [1, 2, 3]. In this dissertation the modelling of the hot rolling mill process is based on a Steckel Hot Rolling Mill. In the Appendix a short definition of common rolling terms are given. 1.1 Background

accuracy in thickness control in metal rolling area. If the required accuracy of hot rolling mills can be achieved, then in some cases, cold rolling is not even required, which can result in a radical decrease of production costs. The schematic structure of a typical aluminum hot reversing rolling mill can be seen in Figure 1.

eccentricity in the rollers, are present inherently in hot rolling mills and their attenuation is achieved by introducing new systems to the milling stands. Hence, the enhancement of the product quality for hot rolling mills is a continuous demand. Hot rolling mills are machines where hot rolling process is realized and rolling is a metal ...

The object of the thesis work was to test assessment and monitoring tools for the control of a hot strip rolling mill. Two control system were also evaluated, work roll bending control and gap control. The effectiveness of a filter, that is used within the control to remove the effect of eccentric rolls, were analyzed.

CiteSeerX - Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): The Force Feed Forward (FFF) System is the only hot strip mill AGC system in the world today which does not incorporate the BISRA principle for gage control. Instead, using a revolutionary control algorithm, FFF has proven in five installations in North and South America, that steelmakers …

Unwind/rewind eccentricity control for rolling mills . United States Patent 4905491 . Abstract: A method of rolling material in a rolling mill in which the material is directed from an unwind coil of the material to the mill and/or to a rewind coil of the material from the mill, the material being under tension as it is directed to and from the ...

Roll eccentricity is an important factor causing thickness variations during hot strip rolling and might define the limit of strip thickness control accuracy. An improved multi-resolution wavelet transform algorithm was proposed to compensate for the roll eccentricity. The wavelet transform method had good localization characteristics in both the time and frequency …

DOI: 10.4236/ENG.2014.61005 Corpus ID: 30768077. Strip Thickness Control of Cold Rolling Mill with Roll Eccentricity Compensation by Using Fuzzy Neural Network @article{Hameed2014StripTC, title={Strip Thickness Control of Cold Rolling Mill with Roll Eccentricity Compensation by Using Fuzzy Neural Network}, author={Waleed Ishaq …

A method for controlling the temperature of a workpiece in a hot strip mill includes calculating temperature changes of the strip at each mill stand location by …

A Cold Rolling Mill rolls, in subsequent short passes(due to the relative thick material), coiled strip from a thickness of up to 8 mm (coming from Hot Rolling Mill) down to 0.2 mm; the mill is designed with high rolling force and power capability and efficient and fast coil handling to minimize the waiting time.

Comprehensive control scheme for the mill (FF: feedforward; FB: feedback; CEC: coil eccentricity compensation; MFC: mass flow control) 20-High Cold Rolling Mill. Feature Highlights of the 20-High Rolling Mill. 1. Wide range of thickness and width for different type of steel strips. Thickness: 0.05-1.2 mm; width: 50 - 1250 mm. Rolling Process Brief

The modeling and control problems are investigated for cold rolling mill system. Firstly, we establish a monitor automatic gauge control (MAGC) model for a practical cold rolling mill system. The new model is with mismatched uncertainties. Then, an extended state observer (ESO) is developed to estimate uncertainties. In the general high-order systems, the ESO is …

Thickness deviations of the steel plates in the rolling mill process is mainly caused by the roll eccentricity of the back up roll (BUR). In this paper, a bandpass filter with high gain in the given frequency is introduced which is able to overcome the roll eccentricity of BUR and is very simple compared with other roll eccentricity control (REC) methods.

Roll eccentricity is widespread in the strip mill, has cyclical impact on strip thickness, so disturbance compensation is required to improve the product quality. The key step of disturbance compensation is to obtain reliable roll eccentricity signal. Existing direct measurements of roll eccentricity signal method requires special equipments with high precision but not practical …

find both eccentricity magnitude and eccentricity location in the roll as shown in Fig.10. But, as shown in Fig.12, not only magnitude of eccentricity but also location of eccentricity in the roll is obtained. 4.2 Simulations with Field Data Fig.13 shows a simplified multi-stand hot rolling system. The rolling system consists of seven stands.

The picture above shows the seamless steel pipe perforation site. The eccentricity of many steel pipes is generated at this time, so it is very important to strictly control this perforation.

On the practical model of Cold-rolling Mill of 300, this paper establishes eccentricity compensation control practice of Cold-rolling Mill of 300 …

In rolling mill, the accuracy and quality of the strip exit thickness are very important factors. To realize high accuracy in the strip exit thickness, the Automatic Gauge Control (AGC) system is used. Because of roll eccentricity in backup rolls, the exit thickness deviates periodically. In this paper, we design PI controller in outer loop for the strip exit thickness while PD controller is ...