Design of Entry Strip Thickness Controls for Tandem Cold Mills

A scraper was attached to an unequal-diameter twin-roll caster without requiring large modifications. This caster was used as a 1000 mm diameter single roll caster equipped with a scraper, and its strip casting ability was tested. The effects of the scraper angle and load, the roll speed, and the pouring temperature of the molten metal on the scribed surface, thickness distribution and average strip thickness were investigated. The scribed surface characteristics were sound and the thickness distribution was flat when the scraper angle was 60° and the scraper load was in the range of 1 to 4 kg. When the scraper load was more than 1 kg, the thickness distribution was uneven. The average strip thickness decreased as the roll speed increased. The pouring temperature of the molten metal influenced the evenness of the solidified layer thickness. The solidified layer became even as the molten metal temperature was decreased. A strip cast with the determined optimal conditions was then cold rolled down to 1 mm to improve its surface quality.

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Ti STRIP PROPERTIES FABRICATED BY POWDER ROLLING METHOD

Surface Review and Letters ◽

10.1142/s0218625x1001393x ◽

2010 ◽

Vol 17 (02) ◽

pp. 229-234 ◽

Cited By ~ 4

Author(s):

JAE-KEUN HONG ◽

CHAE-HUN LEE ◽

JEOUNG-HAN KIM ◽

JONG-TAEK YEOM ◽

NHO-KWANG PARK

Keyword(s):

Rolling Speed ◽

Strip Thickness ◽

Roll Speed ◽

Powder Morphology ◽

Rolling Method ◽

Edge Cracks ◽

Roll Compaction ◽

Ti Powder ◽

Roll Gap ◽

Size Powder

In the present study, the characteristics of the Ti powders fabricated by Hydride–Dehydride (HDH) were analyzed in terms of particle shape, size and size distribution. Ti powders were subjected to roll compaction and their microstructure and green densities were evaluated in terms of particle size, powder morphology, roll gap and rolling speed. Effects of blending elements having different powder sizes on densification properties were analyzed. The strip thickness was proportional to the roll gap up to 0.9 mm and the density of titanium strip was decreased with the increase in roll gap. As the roll speed increased, the strip density and thickness were decreased by using -200 mesh Ti powder. However, the effect of rolling speed for -400 mesh Ti powder was not greater than that of -200 mesh powder. The highest density by 93% was achieved by using -400 mesh Ti powder at 0.1 mm roll gap, however edge cracks and alligator cracks were occurred.

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Analysis of Microstrip Lines with Finite Conductor Strip Thickness by Spectral-Domain Approach

2008 Global Symposium on Millimeter Waves ◽

10.1109/gsmm.2008.4534620 ◽

2008 ◽

Cited By ~ 1

Author(s):

Wu Yanmin ◽

Gao Bo ◽

Chen Yan ◽

Tian Yu ◽

Tong Ling

Keyword(s):

Strip Thickness ◽

Spectral Domain ◽

Microstrip Lines ◽

Spectral Domain Approach ◽

Finite Conductor ◽

Conductor Strip

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A study of nonlinear coupling dynamic characteristics of the cold rolling mill system under different rolling parameters

Advances in Mechanical Engineering ◽

10.1177/1687814017713706 ◽

2017 ◽

Vol 9 (7) ◽

pp. 168781401771370 ◽

Cited By ~ 2

Author(s):

Hai Xu ◽

Ling-Li Cui ◽

De-Guang Shang

Keyword(s):

Fault Diagnosis ◽

Cold Rolling ◽

Dynamic Characteristics ◽

Rolling Mill ◽

Vibration Amplitude ◽

Strip Thickness ◽

Drive System ◽

Nonlinear Coupling ◽

Cold Rolling Mill ◽

Coupling Dynamic

The dynamic characteristics of the mill and the drive system are mutually coupled and affected closed-loop system. However, most research has considered only the vibration of the drive system or the vibration of the mill to determine the cause of the accident in the equipment condition monitoring and fault diagnosis process. Condition monitoring and fault diagnosis based on this type of approach can lead to misdiagnosis or missed diagnosis in determining faults in actual systems. So, in this study, a dynamic model of the coupling between a mill and its drive system was developed to study the interaction of the mill and the drive system with the goal of increasing the accuracy of diagnostic methods and to improve the quality of the rolled material. A nonlinear coupling dynamic model was formulated to represent the relation between the gearbox vibration amplitude and various time-varying parameters to study the effects of various parameters on the drive system vibration characteristic under unsteady lubrication. Simulations results showed that increasing the strip speed, the input strip thickness, or the output strip thickness or decreasing the lubricating oil temperature or the roller radius caused the vibration amplitude of the drive system to increase. The vibration frequency caused by variations in the strip inlet or outlet thickness can be transmitted to the drive system, and gear meshing frequency of the gearbox can be transmitted to the mill. Test data from an actual cold rolling mill verified the accuracy of the model. The model was shown to be capable of simulating the mutually coupled and affected mechanism between a mill and its drive system.

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The Strain of a Plane Sampleat the Homogeneous Field of the Strain Rates under the Plane Strain Conditions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.945.857 ◽

2019 ◽

Vol 945 ◽

pp. 857-865

Author(s):

A.L. Grigorieva ◽

Y.Y. Grigoriev ◽

A.I. Khromov

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Numerical Methods ◽

Strip Thickness ◽

Homogeneous Field ◽

Strain Rates ◽

The Finite Element Method ◽

Strain Fields ◽

Strain Tensors ◽

The Continuum

In this paper, we obtained analytical solutions of the fields of strain tensors under uniaxial tension of a rigidplasticstrip underthe conditions of a plane stress state.The topicalityof the construction of these solutions is connected with significant difficulties in determining the strain fields by numerical methods (for example, the finite element method).In the construction of these solutions, the change in the geometric characteristics of the strip (thickness, width) was taken into account, which led to the solution of the nonlinear problem of the continuum mechanics.

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Effect of As-Cast Strip Thickness and Reduction Prior to Soft Annealing on the Formability of Twin-Roll Cast 5754 Sheets

Light Metals 2016 ◽

10.1007/978-3-319-48251-4_173 ◽

2016 ◽

pp. 1037-1041

Author(s):

Onur Meydanoglu ◽

Cemil Işıksaçan ◽

Mert Günyüz ◽

Onur Birbaşar ◽

Hatice Mollaoğlu Altuner

Keyword(s):

Strip Thickness ◽

Cast Strip ◽

Twin Roll Cast ◽

Twin Roll

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H∞ Preview Control for Discrete-Time Systems

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.1286869 ◽

1999 ◽

Vol 123 (1) ◽

pp. 117-124 ◽

Cited By ~ 5

Author(s):

Chintae Choi ◽

Tsu-Chin Tsao

Keyword(s):

Discrete Time ◽

Controller Design ◽

Problem Formulation ◽

Strip Thickness ◽

Feedback Controller ◽

Algebraic Riccati Equation ◽

Worst Case ◽

The Future ◽

Unknown Disturbances ◽

Tandem Cold Mill

A preview controller to be able to prepare a plant with the future information for external disturbances will guarantee better performance to suppress their effects. A design approach for the optimal H∞ preview controller in the discrete-time domain is given. The preview and feedback controller are simultaneously designed to minimize the worst case RMS value of the regulated variables when the bounded unknown disturbances and the previewable disturbances hit the dynamic plants. Thus, a state feedback controller and the related preview controller are derived in this design, even though problem formulation and solving an algebraic Riccati equation are based on the full-information H∞ controller design scheme. The performance of the proposed preview controller is simulated with a rolling stand of the tandem cold mill in the steel-making works. The objective of the control system for the rolling stand is to minimize thickness error of the exit strip and tension variation between stands simultaneously. The entry strip thickness to the stand and the roll gap variation are considered as previewable disturbances, since they can be measured and estimated. The future informations of these physical variables are utilized in the preview controller to suppress their effects on the exit strip thickness and the inter-stand tension. The simulation results shows that the H∞ preview controller is effective to satisfy the requirements for the thickness and the tension.

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