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Not just aluminium; optimising steel rolling - Innoval ...

Our blog ' Mill Vibration Phenomena during Cold Rolling ' describes the different modes of mill vibration. Third octave gauge chatter and fifth octave chatter are two common forms of mill vibration that are difficult to solve. Both can cause significant strip quality issues if …

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an analysis of the variable urge vibration mill s milling ...

The MillSlicer utilises vibration sensors and digital signal processing technology to provides information Mill Vibration Phenomena during Cold Rolling - Innoval ...,The simplest type of mill vibration is found in all mills. It is a forced vibration due to roll eccentricity and so occurs at roll rotation frequencies.

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Vibration Instability in Rolling Mills: Modeling and ...

Models for the occurrence of the vibrational instability during rolling known as third octave chatter are presented and discussed. An analysis of rolling mill chatter was performed for the purpose of identifying characteristics of the vibrations and to determine any dependency on the rolling schedule.

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Methodology of Designing Cold Rolling Technology ...

Due to this issue, along with the nonstationary character of rolling and rolling mill load regime, rolling with tension may transform into rolling with pressure, which results in enhanced energy consumption, while a rapid change in rolling with pressure and tension may lead to the emergence of adverse self-excitation vibrations on cold rolling ...

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CHATTER DETECTION USING PRINCIPAL COMPONENT …

Keywords: Chatter, Principal Component Analysis (PCA), cold rolling, vibration 1. INTRODUCTION In cold roll mill alternate dark & bright bands are often observed on rolled strip surface along the length of the coil perpendicular to rolling direction. These bands on strip surface are called chatter mark defect shown in Fig. 1.

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Experimental and Numerical Investigation of the Vibration ...

3.1. Vibration Measurement of the Rolling Mill The cold rolling process is usually conducted with a workpiece that is initially at room temperature. A schematic illustration of the 6-high cold rolling mill is shown in Fig. 1.11) The stands are arranged to produce a sequential reduc-tion in the thickness of the strip. Work rolls are the tools

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Working-Stand Equipment Vibrations of Continuous Cold ...

Abstract The article considers the nature, occurrence mechanism and development of resonant vibrations found in the working stand equipment of cold rolling mills during the production of strips with a thickness of 0.4–0.6 mm at speeds of more than 12 m/s. Vibration causes are possibly based on changes in the metal properties during rolling due to …

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THE STUDY OF INFLUENCE OF WORK ROLLS VIBRATION …

elastoplastic deformation during cold rolling and its surface quality. MODEL DESCRIPTION In order to reveal the mechanism of defects occur-rence on the surface of steel cold rolled strips during work rolls vibration, the finite element method imple-mented in the DEFORM-2D program was used. The 4th stand of the 5-stand mill 1700 of PAO Severstal ...

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(PDF) VIBRATION MONITORING OF TANDEM MILLS AT …

chatter vibration can affect both the quality and production capacity of cold rolled steel if it is not properly monitored and reduced. 3rd order octave chatter is a self-generating resonance...

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Large AC Adjustable Speed Motors for Metals Rolling Mills

to vibration with a very low resonance frequency. The stator core is constructed with ... torque in order to prevent loosening of constituent parts during heavy impact loads in the rolling mill and/or frequent reversing operations. Such preventative measures ... • Example: Motors used for continuous hot strip mills, cold tandem mills, cold

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Calculation of stiffness parameters and vibration analysis ...

According to the vertical vibration phenomena existing in cold rolling mills, the unsteady lubrication mechanism in roll gap and its influence to rolling stability was …

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Study on vibration characteristics of rolling mill based ...

The vertical vibration often occurs during the rolling production, which has an influence on the accuracy of rolling mill. In order to effectively suppress the vertical vibration of the rolling equipment, the rolling mill model with vibration absorber device was established. Based on the main resonance singularity of the rolling mill system, the best combination of opening …

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(PDF) Regenerative chatter vibrations control in the ...

Chatter vibrations were investigated for the high speed 5 stand 4-h tandem cold rolling mill 2030 of the NLMC. Real-time chatter vibration monitoring and diagnostics system was developed and ...

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Influence of asymmetric structure parameters on rolling ...

Considering the asymmetric structure of a rolling mill system, a chatter model is established by coupling a rolling process model and structure model to describe the asymmetric vibration characteristics. According to this mathematical model, the critical rolling speed is determined by calculating eigenvalues of the characteristic matrix. Model correctness and validity are …

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SMS group : Active chatter damping for cold rolling mills

Mill vibrations (chatter) especially occurring at high rolling speeds affect product quality of the cold-rolled material and thus lead to yield losses and quality issues. Among other supportive measures active chatter damping has turned out to be an effective approach to counteract these problems by significantly reducing vibration issues of ...

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Prediction and analysis of cold rolling mill vibration ...

The mill vibration data was collected from the UCM cold rolling plant. It was believed that mill chatter during cold rolling is due to abnormal periodic oscillations of the rolls in the vertical direction [34], [35]. Heidari et al. [36] used an accelerometer located at the top of the stand to detect the vertical movement of the rolling mill.

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Numerical Simulation and Parameter Design of Strip Cold ...

Gong et al. made a numerical simulation of the roll vibration during the cold rolling in 6-roll mill, and through the analysis of the results, it was considered that the vibration had the minimum value when the rolling speed was 25 m/s. With the further improvement of the flatness standard on the market, as the most mature high-precision cold ...

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Optimization of cold rolling process parameters in order ...

Statistical analysis of the rolling parameters during the vibration of the five-cell cold rolling mill was conducted by Makarov et al. [7]. Brusa and Lemma [8] analyzed the dynamic effects in ...

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Vibration analysis and numerical simulation of rolling ...

Layout of a 5-stand tandem cold rolling mill. Chatter can be regarded as a type of self-excited vibration. Because interactions occur between the structural dynamics of the mill and the rolling process, this phenomenon is subsequently observed when the external excitation force changes the roll gap and rolling speed.

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Dynamic analysis and control of strip mill vibration under ...

According to the "Hill rolling force formula", taking particular account of the influence from horizontal vibration of rolled piece in roll gap, a dynamic rolling force model is analyzed. Considering the interaction between vibration of strip and roll, the dynamic vibration model of rolling mill is established. On this basis, the time delayed feedback is introduced to control …

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Model for the solution of metal rolling mill vibration ...

In common with other rotating machines, rolling mills are prone to many different vibrations during rolling and most do not cause a problem. However, there are several types of rolling mill vibration that can have a significant impact on the quality …

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A Review on Chatter Analysis in Cold Rolling process

variation due to roll vibration, friction and cooling during process. According to the frequency of vibrations, generally there are three kind of vibration consider during cold roll forming which may influences chatter marks [4] such as: a. Low frequency torsional vibration (5-20Hz) which is associated with drive train and small thickness ...

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CHATTERBLOCK CHATTER VIBRATION IN COLD ROLLING*

and 150Hz, is a self-excited vibration phenomena typically occurring in the rear stands of tandem cold mills. It can produce significant gauge variations and even cause strip breaks. 3rd octave mill chatter is characterized by a quickly diverging vertical vibration of the rolls for specific rolling conditions (material, mill speed, forces,

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Tandem strip mill's multi-parameter coupling dynamic ...

The rolling process is determined by the interaction of a number of different movements, during which the relative movement occurs between the vibrating roll system and the rolled piece, and the roll system's vibration interacts with the strip's deformation and rigid movement. So many parameters being involved leads to a complex mechanism of this …

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Coupling vibration model for hot rolling mills and its ...

Keywords: rolling mill vibration, coupling dynamic model, AGC, mill modulus control gain. 1. Introduction The mill vibration has become a bottleneck in the thin steel strip manufacturing [1, 2], as the mill vibration can cause unacceptable product quality degradation in the steel strip, and even severely damage the mill equipment [3, 4].

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Chatter in Cold Rolling - ScienceDirect

A basic theory of chatter in. cold rolling is presented which is based on the effect of the variable scrip tension on the rolling force as well as on the variations of contact length The structure of a computer program simulating chatter of a tandem mill is presented and examples given of the effect of rolling speed, strip width, coefficient of friction and of using a tuned damper.

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Research on strip hysteretic behavior and mill vertical ...

Rolling mill vibration is a technical problem in the iron and steel industry for many years and has serious impact and harm on production. There were serious vibrations in the middle mills when rolling thin container strip for the compact strip production (CSP) strip hot rolling process. This paper studied the hysteretic characteristic of rolled strip and established …