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Forged Rolling Mill Rolls. Over the years, NKMZ has supplied over 1.3 million tonnes of rolls to more than 43 countries and is currently producing 20,000-25,000 tonnes of forged rolling mill rolls per annum. NKMZ rolling mill rolls are made with alloy forged steel with Chromium content of 2%, 3% and 5%. They are used in different types of ...

ARTICS Hot Rolling Mills Real time control for Hot Rolling Mills. With more than 50 years of experience, Nidec Industrial Solutions has developed a vast array of functions based on auto-adaptive mathematical models that optimize rolling schedule calculations in real time.

If a mill stand is fitted with hydraulic pistons in series with, or instead of the electrically driven mechanical screws, then it is possible to eliminate the effect of that stands back-up roll eccentricity. While rolling, the eccentricity of each back-up roll is determined by sampling the roll force and assigning it to the corresponding ...

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 rolling force.

A finishing mill performs a set of operations in Received in revised form 1 October 2008 a hot strip rolling mill, and is a complex unit including many processes and control loops. ... one which is not carried in by the strip, is roll eccentricity. Roll eccentricity is a general term implying the out-of-roundness of backup and work rolls, or a ...

Hot rolling mill operators and technologists now have access to insights not available with traditional radiometric gauging technology. Laser ultrasonics is the only technique that allows for direct, true, single-wall thickness measurements.

aluminum hot rolling mill — high-quality product, maximum yield, superior flexibility Primetals Technologies provides a full range of aluminum hot rolling mills for both new and revamp projects. With our flexible mill configuration, high-quality strip can be rolled in capacities between 100,000 to 800,000 tonnes per annum.

Roll eccentricity is not part of the controller but must be considered to be consistent with data reported from operating mills which . Figure 3. Effects of roll eccentricity on output strip thick- ness. usually includes its effects. The eccentricity components remaining in the mill exit thickness after compensation.

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.

These studies had concentrated to improve the mill stretch design and the rolling speed control in order to accomplish fine thickness with respect to …

The invention relates to the control of rolling mill backup roll eccentricity by combining the load carrying characteristics of rolling mill tapered roller bearing assemblies during rolling with prescribed levels of axial thrust to effect a controlled deflection of backup roll necks on a 4-high rolling mill or the like due to the selected thrust force applied axially to the ends or necks of ...

casted steel slabs and rolled in two stands down to desired thickness. The first stand is a conventional roughing mill. The last stand is a steckel mill. It is a special rolling technique that is only used in a small number of hot strip mills in the world. When this special technique is used, the demand on the control is high.

The hot metal is passed between two rolls to flatten it, lengthen it, reduce the cross-sectional area and obtain a uniform thickness. Hot-rolled steel is the most common product of the hot rolling process, and is widely used in the metal industry either as an end product or as raw material for subsequent operations.

However, roll eccentricity caused by non-uniform thermal expansion or inexact roll grinding can introduce a thickness error of 40 µm and even more in …

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.

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.

In this study, a new diagnosis method for roll eccentricity under the roll speed changes was developed. The new method was induced from analyzing the rolling mechanism by using rolling force models, radius-speed relationship, and measured rolling force, etc. Simulation results by using the field data show that the proposed method is very useful.

The hot rolling mill environment is quite harsh, so the X-ray thickness gauge is placed a few meters away from the roll gap. The dead time can be …

A rolled plate with uniform thickness and flatness from a rolling mill is a goal constantly pursued by many steel plate manufacturers. Among the various factors which affect the thickness and flatness of the rolling plate, eccentricity of the backup roll is most decisive.

The invention relates to a Steckel hot rolling mill comprising at least one reversing roll stand ( 1 ) as well as coilers ( 6,7 ) which are positioned upstream and downstream and present torque-controlled drives. The aim of the invention is to improve such a hot rolling mill in such a way that it optimally counteracts variations in tension and/or mass flow caused by changes in process ...

A key characteristic of roll eccentricity disturbances is that they are not stationary. That is. although the initial waveform for each roll may be the resul t of grinding practices and bearing characteristics. the resultant waveform due to all rolls may change due to non-uniform thermal expansion and wear. and other factors.

Roll-Eccentricity Compensation (REC) eliminates the influence of roll eccentricity on strip thickness or tension. ISSUE #06 (MAR 18) 01.03.2018

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 …

Roll eccentricity is a periodic disturbance caused by a structure of back up rolls in rolling mills, and it affects product thickness accuracy. It cannot be measured directly by sensors, so it should be identified by measured thickness or measured roll force. When there is a large difference of diameters between top and bottom back up roll, the performance of roll eccentricity control …

hot rolling mill roll eccentricity. Abstract This paper is concerned with the active compensation of the roll eccentricityinduced periodic disturbances in the strip exit thickness of hot and cold rolling mills The roll eccentricity may be caused by different reasons like eg inexact roll grinding or nonuniform thermal expansion of the rolls.

Roll-Eccentricity Compensation (REC) eliminates the influence of roll eccentricity on strip thickness or tension. ISSUE #06 (MAR 18) 01.03.2018

The rolling process is shown in Fig. 2.1: Rolling is done both hot and cold. It is accomplishes in rolling mills. A rolling mill is a complex machine having two or more working rollers, supporting rollers, roll stands, drive motor, reducing gear, flywheel, coupling gear etc. Rollers may be plain or grooved depends upon the shape of rolled product.

These backup rolls are larger and contact the back side of the smaller rolls. A four-high mill has four rolls, two small and two large. A cluster mill has more than 4 rolls, usually in three tiers. These types of mills are commonly used to hot roll wide plates, most cold rolling applications, and to roll foils. [9]

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

GB2059316A GB8029087A GB8029087A GB2059316A GB 2059316 A GB2059316 A GB 2059316A GB 8029087 A GB8029087 A GB 8029087A GB 8029087 A GB8029087 A GB 8029087A GB 2059316 A GB2059316 A GB 2059316A Authority GB United Kingdom Prior art keywords workpiece temperature change mill spray Prior art date Legal status …

P. Kucsera et al. Hot Rolling Mill HGC Thickness Control Improvement – 98 – Another way to determine the thermal expansion of the work roll is the modelling of the heat transfer between the work rolls and the strip.

Online Eccentricity Monitoring of Seamless Tubes in Cross-Roll Piercing Mill Wall-thickness eccentricity is a major dimensional deviation problem in seamless steel tube production. Although eccentricity is mainly caused by abnormal process conditions in the cross-roll piercing mill, most seamless tube plants lack the monitoring at the hot

Fig 2 work roll bending and continuous varying crown. Roll eccentricity compensation – Roll eccentricity is a periodic disturbance caused by a structure of back up rolls in rolling mills, and it affects product thickness accuracy. It cannot be measured directly by sensors, so it should be identified by measured thickness or measured roll force.

The eccentricity disturbance is modeled as white noise w_e driving a band-pass filter Fe. The input thickness disturbance is modeled as white noise w_i driving a low-pass filter Fi. Feedback control is necessary to counter such disturbances. Because the roll gap delta cannot be measured close to the stand, the rolling force f is used for feedback.

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 (one per axis) positioned by hydraulic actuators.

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 …

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.

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 …

Hot rolled steel involves rolling the steel at high temperatures, where cold rolled steel is processed further in cold reduction mills where the material is cooled followed by annealing and/or tempers rolling. Hot Rolled Steel. Hot rolling is a mill process which involves rolling the steel at a high temperature (typically at a temperature over ...