Primer on Flat Rolling

Dedication

Preface to the Second Edition

Preface to the First Edition

Contributors

Acknowledgements

1. Introduction

1.1 The Flat Rolling Process

1.2 The Hot Rolling Process

1.3 Continuous Casting

1.4 Mini-Mills (See Also Chapter 2)

1.5 The Cold Rolling Process

1.6 The Warm Rolling Process

1.7 Further Reading

1.8 Conclusion

2. History of Hot Strip Mills

2.1 Hot Strip Mill Evolution

2.2 Early Hot Strip Mills

2.3 Early Steckel Mills

2.4 Generation I Hot Strip Mills (USA)

2.5 Generation II Hot Strip Mills (USA)

2.6 Other Generation I and II Hot Strip Mills

2.7 Generation III – Coil Box Hot Strip Mills

2.8 Thin Slab Hot Strip Mills

2.9 Newer Generation II Hot Strip Mills

2.10 Modern Steckel Mills

2.11 Hot Mill Electrical Systems

2.12 Hot Strip Mill Innovations

2.13 Revamped Hot Strip Mills

3. Roll Design

3.1 Introduction

3.2 General Overview

3.3 Historical Development of Rolls for Rolling Mills

3.4 Roll Wear

3.5 Friction and Wear

4. Flat Rolling – A General Discussion

4.1 The Flat Rolling Process

4.2 The Physical Events Before, During and After the Pass

4.3 The Metallurgical Events Before and After the Rolling Process

4.4 Limitations of the Flat Rolling Process

4.5 Conclusion

5. Mathematical and Physical Modelling of the Flat Rolling Process

5.1 A Discussion of Mathematical Modelling

5.2 A Simple Model

5.3 1D Models

5.4 Refinements of the Orowan Model

5.5 The Effect of the Inertia Force

5.6 The Predictive Ability of the Mathematical Models

5.7 The Friction Factor in the Flat Rolling Process

5.8 Extremum Principles

5.9 Comparison of the Predicted Powers

5.10 The Development of the Mechanical Attributes of the Rolled Strip

5.11 Miscellaneous Parameters and Relationships in the Flat Rolling Process

5.12 How a Mathematical Model Should Be Used

5.13 Conclusions

6. An Advanced Finite Element Model of the Flat, Cold Rolling Process

6.1 Introduction

6.2 Modelling the Flat Rolling Process

6.3 Experiments

6.4 Results

6.5 Comparison of the Experimental and Numerical Results

6.6 Conclusion

6.7 Acknowledgements

7. Flat Rolling – Simulation and Reduction of Local Buckles in Cold Rolling

7.1 Introduction

7.2 Strain Rate Based Strip 3D Deformation Model

7.3 Work Roll Thermal Crown Model

7.4 Roll Stack Deformation Model

7.5 Stress Unloading Model

7.6 Local Buckling Threshold Model

7.7 Local Buckling Shape Model

7.8 Flow Chart of the Main Program

7.9 Model Tuning and Verification

7.10 User Interface

7.11 Base Case for Local Shape Defect Simulation

7.12 Effects of Entry Strip Profile Ridge

7.13 Effect of Local Yield Stress Drop

7.14 Roll Cooling Nozzle Clog or Work Roll Crown Ridge Effect

7.15 Identification of Causes of Local Buckles

7.16 Predicting Limiting Values for Factors Causing Local Buckles

7.17 Reduction of Local Buckles

8. Material Attributes

8.1 Introduction

8.2 Recently Developed Steels

8.3 Steel and Aluminium

8.4 The Independent Variables

8.5 Traditional Testing Techniques

8.6 Potential Problems Encountered During the Testing Process

8.7 The Shape of Stress–Strain Curves

8.8 Mathematical Representation of Stress–Strain Data

8.9 Choosing a Stress–Strain Relation for Use in Modelling the Rolling Process

8.10 Summary

9. Tribology

9.1 Tribology – A General Discussion

9.2 Friction

9.3 Determining the Coefficient of Friction or the Friction Factor

9.4 Lubrication

9.5 Dependence of the Coefficient of Friction or the Roll Separating Force on the Independent Variables

9.6 Heat Transfer

9.7 Roll Wear

9.8 Nanotribology

9.9 Conclusions

10. Applications and Sensitivity Studies

10.1 The Sensitivity of the Predictions of the Flat Rolling Models

10.2 A Comparison of the Power Predictions Required for Plastic Deformation of the Strip

10.3 The Roll Pressure Distribution

10.4 The Statically Recrystallized Grain Size

10.5 The Critical Strain

10.6 The Hot Strength of Steels – Shida’s Equations

11. Hot Rolling of Aluminium

11.1 Introduction

11.2 Hot Rolling Process

11.3 Heat Transfer

11.4 Deformation

11.5 Microstructure Changes During Hot Rolling

11.6 Summary

12. Temper Rolling

12.1 The Temper Rolling Process

12.2 The Mechanism of Plastic Yielding

12.3 The Effects of Temper Rolling

12.4 Mathematical Models of the Temper Rolling Process

12.5 Summary

13. Severe Plastic Deformation – Accumulative Roll Bonding

13.1 Introduction

13.2 Manufacturing Methods of Severe Plastic Deformation

13.3 A Set of Experiments

13.4 Results and Discussion

13.5 The Phenomena Affecting the Bonds

13.6 A Potential Industrial Application: Tailored Blanks

13.7 A Combination of ECAP and ARB

13.8 Conclusions

14. Roll Bonding

14.1 Introduction

14.2 Material, Equipment, Sample Preparation and Parameters

14.3 Results and Discussion

14.4 Examination of the Interface

14.5 The Phenomenon of Bonding

14.6 Conclusions

15. Flexible Rolling

15.1 Introduction

15.2 Material, Equipment, Procedure and Sample Preparation

15.3 Results and Discussion

15.4 Predictions of a Simple Model

15.5 Strain at Fracture

15.6 Conclusions

16. Problems and Solutions

Part 1 Problems

Part 2 Solutions

Appendix

List 1 Early USA Hot Strip Mills (Throughputs in Short Tons)

Total Annual Capacity: 17,616,000 TPY

List 3 USA Generation I Hot Strip Mills (Throughputs in Short Tons)

Total Annual Capacity: 55,809,000 TPY

Total Annual Capacity: 34,700,000 TPY

List 6 Worldwide Coil Box Hot Strip Mills

List 7 SMS Siemag Thin Slab Hot Strip Mills

List 8 Mannesmann Demag Thin Slab Hot Strip Mills

List 9 Some of the Danieli Thin Slab Hot Strip Mills

List 10 Misubishi Hitachi Thin Slab Hot Strip Mills

List 11 Arvedi Cremoni/Siemens VAI ESP Thin Slab Hot Strip Mill

List 12 Some of the Newer Generation II Hot Strip Mills

List 13 Some of the Modern Steckel Mills

References