A method and device for controlling the final thickness of a rolled product at a tandem rolling mill exit which make it possible to remove the cyclic defects of the product thickness variation. The method includes using at least one rolling stand provided with hydraulic adjustment devices located on the tandem rolling mill exit and in compensating the cyclic defects of the product thickness ...

The roll eccentricity in a rolling mill may define the limit of achievable thickness tolerances and thus is subject of interest for the automation equipment in hot rolling mills as well as in cold rolling mills. Today's demand on thickness tolerances less than 0.8% require efficient methods for roll eccentricity identification and compensation.

motors. These are known as mill stands. The layout of a rolling mill varies, from a simple single stand mill to several stands positioned either side by side or in a line. A mechanism, commonly called a roller table, directs the work piece to the rolls, and another roller table for …

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 ...

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

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-

Awtm/ia Abstract: An in-depth review of the roll eccentricity control design problem is prov­ided which encompasses a number of recent, novel, design contributions and includes experimental results from two separate steel, tandem cold rolling mill installations. A unifying approach to eccentricity control ~nables the diverse range of published ...

The control of a hot strip rolling mill is a quite complex problem due to the presence of many simultaneous control tasks. This is the main motivation that spurred the major steel corporations to adopt more sophisticated techniques based on multivariable concepts.

This paper considers some of the control issues in hot rolling mills. Hence to set the context, first we give a brief description of a typical process. The role of a hot strip mill process is to roll the slabs produced in a continuous casting process and produce strips of thickness 0.8–20 mm. Fig. 1 shows a typical layout of a hot strip mill.

How To Control Eccentricity Problem In Hot Rolling Mill 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 ...

Roll eccentricity is ubiquitous in strip mills, which has a periodic impact on the strip thickness difference. Roll eccentricity compensation is an important part of the automatic gauge control system. Most roll eccentricity compensations extract the roll eccentricity based on the frequency domain analysis of …

The key equipme nt in hot/cold tand em rolling mills is the finishing mill g roup, which usually consists o f 7 mill stands in hot rolling and 5 mill stands in cold rolling.

Rolling Stand Model. Figures 1 and 2 depict the process of shaping a beam of hot steel by compressing it with rolling cylinders. Figure 1: Beam Shaping by Rolling Cylinders. Figure 2: Rolling Mill Stand. The desired H shape is impressed by two pairs of rolling cylinders …

LQG Regulation: Rolling Mill Case Study Overview of this Case Study. This case study demonstrates the use of the LQG design tools in a process control application. The goal is to regulate the horizontal and vertical thickness of the beam produced by a hot steel rolling mill.

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 …

Firstly this paper proposes a lumped-parameter hot-rolling mill model. The rolling mill examined is reversible and equipped with an independent speed control system for each work roll (two single ...

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 need not replace their ...

rolling set-up model mill to maximize the throughput of the mill. In research on the control system, Geddes [9]and Geddes and Postlethwaite [10] discussed the H∞ loop-shaping method from thread to full speed and studied multi-variable control systems using Η∞ design by simulation. Pittner et al. [11] and Pittner and Simaan [12]designedthe

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 the capillary wall. (1) Head.

CONTROL TECHNOLOGY IN HOT ROLLING MILLS Il Seop Choi∗, Anthony Rossiter∗, Peter Fleming∗ ∗ Automatic Control & Systems Engineering University of Sheffield Sheffield S1 3JD, UK cop01isc@sheffield.ac.uk Abstract: Looper and tension control is important in hot strip mills because it affects the strip quality as well as strip threading.

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 ...

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 …

On the practical model of Cold-rolling Mill of 300, this paper establishes eccentricity compensation control practice of Cold-rolling Mill of 300 which applies wavelet transform method.

A control system and method are disclosed to operate with at least one roll stand of a rolling mill to determine the magnitude and phase relationship of the eccentricity of each back-up roll of a four high roll stand, to monitor the rotation of the back-up rolls during the rolling process, and for each back up roll to correct the roll vertical position as a function of the roll angular ...

3.1 Key Feature of Process Control: Detection of Periodic Defects Rolls and rollers are the most heavily used parts of a rolling mill. Due to wear from contacting hot material with great force, their lifetime is limited. Although rolls are refurbished in the roll shop regularly, they occasionally crack before the end of the usual production cycle.

the same time, the increased running speed brings out possible vibration problems in the rolling process, especially in a cold strip mill. If the thickness variation of the hot-rolled aluminum strip can be reduced, it will be possible to increase the production speed of the cold strip mill. These claims set new demands on the acceptable rolling

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 ...

difference of the hot rolling, the eccentric control of hot rolling roll is one of the hot topics in the current research. (3) X-ray thickness monitoring Mill thickness automatic control is mainly based on the GM-AGC, while considering the factors of various compensation, but its accuracy still is less than X - ray thickness gauge [12].

how does the clinker grinding unit, learnpianoin a cement grinding unit total function deffination Cement mill what is the definition How Grinding Unit Cement . how does a grinding cement mill work - sbnshikshansansthan.in ... Control Problems ... In this way disturbances arising at a unit propagate to the ... Vol. XIX - Automation and Control ...

been developed for hot or cold mill processes. The Brit-ish Iron and SteelResearch Association (B1SRA) AGC method based on the gaug meter principle and the feede forward AGC method using the delivery time of the strip have been widely utilized in steel rolling mills [3]. Strip products thickness precision is an important quality parameter.

Recording of a rolled strip at a six stand hot strip mill 3.5 Conclusions Motivated by the increasing requirements for the thickness tolerances in hot-strip mills, a fast and active roll-eccentricity-compensation method has been developed, which deals with conventional measuring signals.

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.

The Hot Rolling Process The primary function of the Hot Strip Mill is to reheat semi-finished steel slabs of steel nearly to their melting point, then roll them thinner and longer through 12 successive rolling mill stands driven by motors totaling 77,000 hp, and finally coiling up the lengthened steel sheet for transport to the next process.