Extrusion in Ceramics (eBook)

Frank Händle (Herausgeber)

eBook Download: PDF

2007 | 2007
XI, 413 Seiten
Springer Berlin (Verlag)
978-3-540-27102-4 (ISBN)

Infos

Frank Handle ¨ 1.1 What to Expect For some time now, I have been toying around with the idea of writing a book about 'Ceramic Extrusion', because to my amazement I have been unable to locate a single existing, comprehensive rundown on the subject - much in contrast to, say, plastic extrusion and despite the fact that there are some outstanding contributions to be found about certain, individual topics, such as those in textbooks by Reed [1], Krause [2], Bender/Handle ¨ [3] et al. By way of analogy to Woody Allen's wonderfully ironic movie entitled 'Eve- thing You Always Wanted to Know about Sex', I originally intended to call this book 'Everything You Always Wanted to Know about Ceramic Extrusion', but - ter giving it some extra thought, I eventually decided on a somewhat soberer title. Nevertheless, my companion writers and I have done our best - considering our target group and their motives - not to revert to the kind of jargon that people use when they think the less understandable it sounds, the more scienti c it appears. This book addresses all those who are looking for a lot or a little general or selective information about ceramic extrusion and its sundry aspects. We realize that most of our readers will not be perusing this book just for fun or out of intellectual curiosity, but because they hope to get some use out of it for their own endeavours.

Inhalt

Contents 6
List of Contributors 8
Acknowledgements 10
Introduction 11
1.1 What to Expect 11
1.2 History of an Obsession 12
1.3 About the Various Contributions 15
1.4 Famous LastWords 18
References 21
Shaping in Ceramic Technology – An Overview 23
2.1 Dry Pressing 24
2.2 Extruding 31
2.3 Slip Casting 33
References 40
Current Classification of Ceramic Materials 44
3.1 Classification by Application or Chemical-Mineralogical Structure 44
References 65
Types of Extrusion Units 67
4.1 Classification by the Range of Application 68
4.2 Classification by the Product to be Extruded 70
4.3 Classification by the Arrangement of the Auger Shaft and Direction of Column Exit 70
4.4 Classification by the Diameter of the Extruder Barrel 73
4.5 Classification by the Number of Auger Shafts 74
4.6 Classification by the Consistency of the Body to be Processed 76
4.7 Classification by the Design of the Extruder Barrel 77
4.8 Classification by the Design and Mounting of the Augers 80
4.9 Classification by Specific Extrusion Method 81
4.10 Classification by the Type of De-Airing Device Employed 85
4.11 Classification by the Extruder Design Features 85
4.12 Classification by the Design of the De-Airing Mixer 89
4.13 Classification by the Design Version of the Combined De- Airing Extrusion Unit 89
References 92
A Short History of the Extruder in Ceramics 93
5.1 The Development of the Extruder and Column Shaping 94
5.2 The Development of Individual Extruder Components 109
5.3 The Development of the Vacuum Extruder and Combined De- Airing Extrusion Unit 126
5.4 The Extruder in the Different Fields of Ceramics 129
5.5 Chronology of Extrusion in Ceramics 132
References 135
The Principle of the Auger Extruder 137
6.1 Introduction 137
6.2 Liquid Phase and Additives 137
6.3 Physics of Process Steps 138
6.4 Engineering Implementation 142
6.5 Other Types of Product 144
6.6 Range of Product Size and Shape 146
6.7 Other Technologies 146
6.8 Final View 147
References 148
Rheology of Ceramic Bodies 149
7.1 Introduction 149
7.2 The Material Law 149
7.3 Dynamic Consideration of Cylindrical-Tube Pressure Flow of Bingham Media with Wall Slippage 156
7.4 True Flow Curve 158
7.5 The Rheological Simulation Model 161
7.6 Summary and Prospects 165
References 167
Rheology and Extrudability of Ceramic Compounds 168
8.1 Introduction 168
8.2 Rheological Test Methods for Describing Extrudability 170
8.3 Summary 178
References 178
Scenarios of Extrusion 179
9.1 Introduction 179
9.2 Functioning of Screw Extruders 179
9.3 Measures 186
9.4 Conclusion 191
References 192
Laminations in Extrusion 193
10.1 Definition 193
10.2 Causes of the Development of Laminations and Different Types of Laminations 194
10.3 De-Airing Laminations 205
10.4 Laminations as a Result of Inhomogeneous Body 207
10.5 Methods for Detection and Evaluation of Laminations 207
10.6 Opportunities for Minimising Detrimental Effects Caused by Laminations 211
10.7 Conclusion 214
References 215
Additives for Extrusion 217
11.1 Introduction 217
11.2 Additive Types 220
11.3 The Chemical Structure and Mechanism of Action of Plasticizing Additives 222
11.4 Summary 225
References 226
Dies, Pressure Heads, Strainer Plates and More 227
12.1 Outline/Introduction 227
12.2 Specific Characteristics of Ceramic Extrusion Body with Regard to Shaping 228
12.3 Factors of Influence to be Considered for the Design of Extrusion Tools 228
12.4 Combination Pressure Head and Die Assemblies for Technical Ceramics 229
12.5 Combination Pressure Head and Die Assemblies in Heavy Clay Ceramics 233
Conclusions 237
12.6 Brief Overview of Tribomaterials Customarily Employed in Ceramic Extrusion Tools 244
12.7 Closing Remarks 245
References 245
Twin-Screw Extruders in Ceramic Extrusion 246
13.1 Introduction 246
13.2 History of Batch and Continuous Kneading 246
13.3 Working Principle of Co-Rotating Twin-Screw Extruders 249
13.4 High-Torque Versus High-Volume Extruders 251
13.5 Compounding Applications with High Solid Contents 254
13.6 Ceramic Extrusion Plants 255
13.7 Summary 262
References 263
Piston Extruders 264
14.1 Piston Extruders in Ceramics 264
14.2 Types of Piston Extruder 264
14.3 The Components of Piston Extruders 265
14.4 The Pros and Cons of Piston Extruders 275
14.5 Auxiliary Equipment 275
14.6 Development 277
14.7 Literature 278
Evacuation in Ceramic Extrusion – Dependences and Local Situations 279
15.1 Vacuum Measurement 280
15.2 Percent Vacuum as a Function of Site Elevation, Parameter: Temperature of Extrusion Compound 281
15.3 Percent Vacuum as a Function of Weather-Induced Differences in Air Pressure Parameter: Temperature of Extrusion Compound 282
15.4 Physical Interdependences 282
References 283
Evacuation Technology for Ceramic Extrusion 284
16.1 Introduction 284
16.2 Liquid-Ring Vacuum Systems 284
16.3 Vacuum Systems with Rotary Vane Vacuum Pumps 287
16.4 Vacuum Systems with Dry-Running Vacuum Pumps 289
16.5 Vacuum Pump Combinations 291
16.6 Components of the Vacuum System 293
16.7 Control and Regulation 296
16.8 Summary 296
References 297
Thermoplastic Extrusion for Ceramic Bodies 298
17.1 Introduction 298
17.2 Thermoplastic Extrusion Processing 300
17.3 Thermoplastic Extrusion Processing 304
17.4 Conclusion 313
References 313
Tribological Principles 315
18.1 Tribological System 315
18.2 ElementaryWear Processes 318
References 322
Measures for Protection Against Abrasion on Screws Used in Extruding Ceramic Compounds 323
19.1 Protection Against Abrasion by Using the Appropriate Material 323
19.2 Layer-Based Abrasion Protection 325
References 331
Perspectives forWear Reduction with Ceramic Extruder Components 332
20.1 Introduction 332
20.2 Properties of Ceramics 332
20.3 Design and Field Testing of Ceramic Augers 337
20.4 Application of a Ceramic Auger in the Production Process for Al2O3 Filtration Tubes 343
20.5 Conclusions and Outlook 346
References 346
Test Methods for Plasticity and Extrusion Behaviour 348
21.1 Actuating Variables 348
21.2 Test Methods to Determine Plasticity 355
References 362
Simulation in Ceramic Extrusion 364
22.1 The Fundamentals 364
22.2 Solution of the Governing Equations 372
22.3 Computational Fluid Dynamics for Ceramic Extrusion 374
References 379
Selected Literature 380
The Authors of the Book 396
Index 410

Produkt-Details

• Erscheint lt. Verlag: 12.6.2007
• Reihe/Serie: Engineering Materials and Processes
• Reihe/Serie: Engineering Materials and Processes
• Zusatzinfo: XI, 413 p. 201 illus.
• Verlagsort: Berlin
• Sprache: englisch
• Themenwelt: Naturwissenschaften ► Chemie
• Themenwelt: Technik ► Maschinenbau
• Schlagworte: advanced ceramics • catalyst • ceramic honeycombs • ceramic profiles • Ceramics • Extruder • extrusions • Kolbenpressen • piston extrusion • Schneckenpressen • Technische Keramik
• ISBN-10: 3-540-27102-3 / 3540271023
• ISBN-13: 978-3-540-27102-4 / 9783540271024