The making, shaping and treating of steel online

THE MAKING, SHAPING

AND

TREATING OF STEEL



BY
J. M. CAMP

AND

C. B. FRANCIS



SECOND EDITION



PUBLISHED BY

THE CARNEGIE STEEL COMPANY

PITTSBURGH, PA.









Copyright 1920 by

CARNEGIE STEEL COMPANY

Pittsburgh, Pa.



TO

HOMER D. WILLIAMS,

President of the Carnegie Steel Company

AND

HIS ASSISTANTS

For Their Valued Suggestions and Words of Appreciation
THIS BOOK IS DEDICATED



425274



PREFACE TO SECOND EDITION

This book has been written especially for the nontechnical employees
of the Carnegie Steel Company, and others, who, seeking self instruction,
may desire to secure in the shortest time possible a general knowledge of
the metallurgy of iron and steel.

The book is the outcome of several years experience in attempting to
teach the metallurgy of steel to our salesmen and other nontechnical
employees. From the first, the method pursued in this work has been that
of taking the students, under proper guidance, into the mills, where they
obtain, first hand and individually, such information as they desire and
are able to collect, and of supplementing the knowledge gained from these
visits with talks and explanations delivered in a classroom where conditions
are more favorable for this kind 01 instruction than they are in the mills.
These talks, in a condensed form, were put in writing, and a copy given
to each of the students. As the demand for these lectures increased, it was
decided that, for the sake of convenience, they should be printed; and
accordingly they were re vised and are here assembled in the present volume.

In order to increase the value of the book as a reference book, we
have aimed to condense the information and to avoid every unnecessary
word, both by omitting all matter from the text not absolutely essential
and by the free use of tables, drawings and diagrams, which we permit to
tell their own story. However, knowing our readers will be men imbued
with a desire to learn, we have not avoided discussing many scientific aspects
of our subjects. But here we have tried to make it easy even for the
general reader. We have aimed to use language as simple as possible,
consistent with clearness, and to treat our subjects in such a way that,
aside from what a limited education supplies, no prerequisites will be
required. We start with the elementary subjects of Physics and
Chemistry, the logical prerequisites, and build our metallurgy upon that
foundation. The book will, therefore, prove of most value to those
connected with the steel business, and not technically educated, who are
really anxious to learn more about the wonderful industry in which they
are engaged. For such as these, we have aimed to make this book at
least a stepping stone to higher and better things.



With regard to the subject matter of the book, we claim but little in
the way of originality. We have no new theories to advance and no new
discoveries to reveal. Our aim throughout has been to describe conditions
and things as they are and to explain the causes for their being as they are,
rather than to tell how they might be or how they ought to be. To
accomplish our first purpose, we have been compelled to rely mainly upon
our personal observation and experiences, but in explaining the causes of
things we have freely consulted all those whose published opinions relating
to each particular subject have been available and of value. We are,
therefore, indebted to many for aid, and to all these we wish to express
our thanks. Wherever we have drawn upon these sources of information
we have aimed to give the credit to the authors by mention in the text
or by foot note references. As guides to collateral reading these
references will have an additional value to our readers. We also desire to
thank the superintendents and the many heads of departments of our various
plants for the courtesies they have shown us and for the many bits of val-
uable information which they were ever ready to give.



TABLE OF CONTENTS

PART I.
MAKING OF STEEL

CHAPTER I Some Principles of Physics and Chemistry

SECTION I. INTRODUCTION

1. Iron, the Master Metal 1

2. Metallurgy defined 2

3. Matter 2

a. Fundamental Laws and States of Matter .... 2

b. Molecules 2

c. Sciences of Matter 3

SECTION II. PHYSICAL PROPERTIES OF MATTER.

1. Classes of Properties 3

a. General Properties: 3

i. Inertia 3

ii. Extension 4

iii. Mass 4

iv. Density and Specific Gravity 4

v. Porosity 4

vi. Impenetrability 4

b. Special Properties 4

i. Cohesion and Adhesion 4

ii. Elasticity 4

iii. Plasticity 5

iv. Ductility 5

v. Malleability 5

vi. Hardness 5

vii. Crystallization 5

viii. Diffusion . . . -. 5

ix. Effusion 5

x. Absorption ." 5

SECTION III. ENERGY, HEAT AND TEMPERATURE AND THE
ETHER:

1. Energy Law of Conservation 5

a. Kinds of Energy Kinetic and Potential . . 6

2. Heat and Temperature 6

a. Effects of Heat Law of gas expansion and

kinetic theory 6

b. Temperature Scales 6

c. Measurement of Heat 7

3. The Ether.. 7



TABLE OF CONTENTS



SECTION IV. CHANGES IN MATTER:

1. Physical and Chemical Changes 8

2. Mechanical Mixtures and Chemical Compounds:

a. Solutions and Alloys 8

b. Acids, bases, salts, and non-electrolytes 8

3. The Chemical Elements 9

a. Classification of the elements 9

b. Chemical Symbols 9

c. Fundamental Laws of Chemical Changes. ... 9
Definite and Multiple Proportions 9

SECTION V. THE ATOMIC AND ELECTRON THEORIES:

1. Atoms 10

a. Atomic weights 10

b. Valence 10

c. Table of Elements with symbols, etc 11

2. Electrons. 13

SECTION VI. CHEMICAL FORMULA AND REACTIONS:

1. Formula of Compounds 13

2. Formula of Molecules of Elements 13

3. Chemical Equations 13

a. Balancing reactions 14

b. Radicals 14

4. Ions and Electrolysis 14

5. Dry and Wet Chemistry 15

a. Acids, bases and "Salts of Dry Chemistry . . 15

b. Table of anhydrides 16

6. Kinds of Reactions 16

7. Laws of Chemical Reactions 17

SECTION VII. CHEMICAL NOMENCLATURE:

1. The General Principle of Nomenclature. . . 18

2. Terminology of Binary Compounds 18

3. Terminology of Ternary Compounds 18

4. Terminology of Acids 18

5. Terminology of Bases 19

6. Terminology of Salts ....... 19

SECTION VIII. CHEMICAL CALCULATIONS:

1. Kinds of Problems 19

2. Problems involving weight only 19

3. Problems involving volume only 20

4. Problems involving weight and volume 21



TABLE OF CONTENTS ix

SECTION IX. DESCRIPTION OF ELEMENTS IMPORTANT IN

IRON AND STEEL MAKING:
/^~*

1. Occurrence, Preparation, Properties and Some

Compounds of Oxygen 22

2. Occurrence, Preparation, Properties and Some

Compounds of Hydrogen 22

3. Occurrence, Preparation, Properties and Some

Compounds of Sulphur 23

4. Occurrence, Preparation, Properties and Some

Compounds of Carbon 23

5. Occurrence, Preparation, Properties and Some

Compounds of Silicon 24

6. Occurrence, Preparation, Properties and Some

Compounds of Nitrogen 25

7. Occurrence, Preparation, Properties and Some

Compounds of Phosphorous 25

8. Occurrence, Preparation, Properties and Some

Compounds of Calcium and Magnesium 25

9. Occurrence, Preparation, Properties and Some

Compounds of Aluminum 26

10. Occurrence, Preparation, Properties and Some

Compounds of Chromium 26

11. Occurrence, Preparation, Properties and Some

Compounds of Manganese 27

12. Occurrence, Preparation, Properties and Some

Compounds of Iron 27

CHAPTER II. Refractories.

SECTION I. NATURE OF REFRACTORIES:

1. Importance 28

2. Requirements of Refractories 28

3. Classes of Refractories 28

SECTION II. ACID REFRACTORIES:

1. Chemical Composition 29

2. Silica Bricks 29

3. Clay 29

a. The Impurities in Clays 29

b. The Process of Making Fire Clay Brick. ... 30



TABLE OF CONTENTS



SECTION III. BASIC REFRACTORIES:

1. Magnesia 30

2. Lime 30

3. Dolomite ...... 31

4. Bauxite 31

SECTION IV. NEUTRAL REFRACTORIES:

1. The Ideal Furnace Lining .?... 31

2. Graphite 31

3. Chromite 31

4. Protection for Refractories 31

5. Table Chemical Analyses of Refractories 32

SECTION V. TESTING REFRACTORIES:

1. Trial Tests and Laboratory Tests. . 33

2. Fusion Temperature 33

3. Resistance to Compression 33

4. Expansion and Contraction 34

5. Slagging Test 34

6. Density 34

7. The Impact Test 35

8. The Abrasion Test 35

9. Spalling Test 35



H AFTER HI. Iron Ores.

SECTION I. ORES AND THE IRON BEARING MINERALS:

1. Minerals and Ores 36

2. The Iron Bearing Minerals 36

a. Magnetite Group 37

b. Hematite Group 37

c. Limonite or Brown Ore Group 37

d. The Carbonate Group 37

3. The Mineralogical Make-up of Iron Ores 37

SECTION II. VALUATION OF ORES:

1. Factors in the Valuation of Ores 38

a. The Impurities that Are Never Reduced in

the Blast Furnace 39

b. The Impurities that May Be Partially

Reduced 39

c. The Impurities Always Reduced 40

d. Water ... 40

e. Accessibility 41



TABLE OF CONTENTS



SECTION III. THE BIRMINGHAM DISTRICT:

1. Location and General Geology 42

2. Method of Mining 42

SECTION IV. THE LAKE SUPERIOR DISTRICT:

1. Importance, Location and General Geology 42

a. The Marquette Range 43

b. The Menominee Range 43

c. The Gogebic Range 43

d. The Vermilion Range 46

c. The Missabe Range 46

f. The Cuyuna Range 47

SECTION V. MINING THE LAKE ORES:

1. Prospecting and Exploration 47

a. Prospecting 47

b. Drjll Exploration 47

2. Methods of Mining 50

a. Open Pit Mining 50

i. Siteamshovel Mining 50

ii. Milling 52

iji. Scramming 53

iv. Advantages of Open Pit Mining 53

b. Underground Mining Slicing 53

i. Advantages of the Slicing System of

Mining 55

ii. Depth of Mine Shafts 55

3. Grading the Ores 55

4. Transporting the Ores 56

5. Mining and Grading in Winter 57

CHAPTER IV. Fuels.

SECTION I. SOME P RE-REQUISITES TO THE STUDY OF FUELS:

1. Introductory 58

2. Sensible and Specific Heat 58

3. Latent Heat and Change of State 59

a. Laws of Fusion 59

b. Laws of Evaporation 59

c. Laws of Ebullition 59

4. Transmission of Heat 59

5. Fuels and Combustion 60

6. Fuels and Chemical Energy ; 60

7. Measurement of Calorific Power t 60

8. The Calorific Power of Some Common Elements . 61

9. Calculating Calorific Power , 61

10. Practical Heat Tests. . 62



Xll



TABLE OF CONTENTS



SECTION I. Continued.

11. Laboratory Heat Tests 62

12. Calorific Intensity 63

13. Methods of Conserving Heat 63

14. Pyrometers 64

a. Specific Heat, or Water, Pyrometer 64

b. Electric Resistance Pyrometers 64

c. Thermo-Electric Pyrometers : 64

d. Radiation Pyrometers 65

e. Optical Pyrometers 65

SECTION II. CLASSIFICATION OF FUELS:

1. Table Classification of Fuels 66

2. Plan of Study 67

SECTION III. INCIDENTAL AND LIQUID FUELS:

1. Incidental Fuels 67

2. Tar 67

3. Petroleum 68

a. Composition of Petroleum 68

b. Hydrocarbons Generalized, Empirical and

Structural Formulas 68

c. Table The Different Homologous Series of

Hydrocarbons 69

d. Fuel Oil and Other Products of Petroleum. 69

SECTION IV. GASEOUS FUELS:

1. Advantages of Gaseous Fuels 70

2. Table Hydrocarbons in Natural Gas and Petroleum 70

3. Natural Gas 71

4. Artificial Gases 71

a. Table Composition of Gaseous Fuels 71

b. Principle of the Gas Producer 71

c . Factors Affecting the Efficiency of the Producer 73

d. The Hughes Producer as an Example of

Mechanically Poked Producer 73

e. Conditions and Reactions 74

f. Operation of the Hughes Producer 75

SECTION V. THE SOLID NATURAL FUELS:

1. Analysis of Solid Natural Fuels: 75

a. Table Analysis of a Solid Fuel, Coal, by

the Three Different Methods 76

2. Wood 76

3. Peat , 77

4. Lignite and Brown Coal 77



TABLE OF CONTENTS xiii

SECTION V. Continued.

5. Table Approximate Analyses of the Different

Solid Fuels 78

6. Diagram Depicting Geologic Periods in which

Gas, Oil, and the Valuable Minerals are Found. . 79

7. Coal 80

a. Bituminous Coal '. . 80

b. Ash in Coal 80

SECTION VI. PREPARED SOLID FUELS:

1. Powdered Coal 81

a. Requirements for Use of Powdered Coal 81

b. Advantages of Powdered Coal 82

c. The Sharon Powdered Coal Plant 82

i. Description of Pulverizing Plant 82

d. Clairton and Homestead Powdered Coal Plants 83

2. Coke 85

a. Methods of Manufacturing Coke 85

SECTION VII. THE BEEHIVE PROCESS FOR THE MANUFACTURE
OF COKE:

1. The Continental No. 1 Plant of the H. C. Frick

Coke Company 86

a. The Mine 86

b. The Coking Plant 86

i. Construction and Arrangement of Ovens 86

ii. Waste Heat System 87

iii. Charging the Ovens 87

iv. The Coking Process 88

v. Watering and Drawing the Coke 89

vi. Longitudinal Ovens 90

SECTION VIII. THE BY-PRODUCT PROCESS FOR MANUFAC-
TURING COKE:

1. General Features of the Process 90

2. Advantages of the By-Product Process 91

3. The Plant of the Clairton By-Product Coke

Company 91

a. Construction of the Ovens 93

b. Heating the Ovens 95

c. Drying and Heating New Ovens 96

d. Operation of the Ovens 96



xiv TABLE OF CONTENTS

SECTION IX. THE BY-PRODUCT PLANT:

1. The Volatile Matter of Coal 98

2. Gas Mains and Coolers 98

3. Separation of the Tar and Ammonia Liquor .... 99

4. Compressors and Tar Extractors 99

5. Recovery of Ammonia , . . . 100

6. Debenzolating the Gas 101

SECTION X. THE BENZOL PLANT:

1. Light Oil 101

2. Composition of Light Oil 102

3. Construction and Principles of the Still 102

4. Operation of the Crude Still 102

5. Washing the Products of the Crude Stills 103

6. The Pure Stills 103

SECTION XI. SOME PROPERTIES AND USES OF THE RAW BY-
PRODUCTS FROM THE COKE WORKS:

1. Characteristics of Benzol, Toluol and Naphtha 105

a. Some Members of the Benzene Series, and

their Physical Properties 106

2. Commercial Benzol 107

a. Uses of Commercial Benzol 107

b. Motor Benzol. 107

3. Properties and Uses of Pure Benzol, or Benzene. . . . 109

a. Table Diagram Showing Some of the

Products Derived from Benzene, Their

Formulas and Their Uses 108

b. Table Reactions Showing How Phenol,

Picric Acid and Resorcinol may be

Derived from Benzene 110

c. Table Reactions Showing How Aniline and

Benzidine are Derived from Benzene 109

4. Usesof Toluene Ill

a. Table Some Products Derived from Toluene,

Their Formulas and Uses 112

b. Commercial Toluol and Solvent Naptha Ill

5. Uses of Naphthalene 113

a. Table Showing Some Products Derived

from Naphthalene 114

6. Tar 114

a. Diagram Illustrative of the Refining of Tar . 115

7. Ammonia 118

a. Ammonium Sulphate 116

b. Use of Ammonium Sulphate as a Fertilizer. . 116



TABLE OF CONTENTS



CHAPTER V. Fluxes and Slags.
SECTION I. FLUXES:

1. Smelting and the Functions of a Flux 117

2. The Selection of the Proper Flux for a Given Process 117

3. Acid Fluxes 118

a. Alumina 118

4. Basic Fluxes 118

a. Available Base 118

b. Limestone 119

c. Supply of Limestone 119

d. Action of Limestone in Furnaces 119

5. Neutral Fluxes 120

SECTION II. SLAGS:

1. Slag 120

2. Functions of Slags 120

3. Importance of Slags , 120

4. Chemical Composition of Slags 121

5. Relation of Acids to Bases in Blast Furnace Slags. . 121

6. Ratio of Acids to Bases in Open Hearth Slags 122

7. Acid to Base in Acid Furnaces 122

8. Electric Steel Furnace Slags 122

9. Acids Formed by Silicon . . 122

10. So-called Acid and Basic Slags 123

11. Classification of Slags.... 123

12. Uses of Slags 124

CHAPTER VI. The Manufacture of Pig Iron.

SECTION I. SOME INTERESTING HISTORICAL FACTS:

1. Early History of Iron 125

2. Old American Furnaces 126

3. The Importance of Iron 126

SECTION It. COMPOSITION AND CONSTITUTION OF PIG IRON:

1 1. Constitution of Pig Iron 126

2. Chemical Elements in Pig Iron 127

a. Carbon 127

b. Silicon 127

c. Manganese 128

d. Sulphur 128

e. Phosphorus 129

3. Grading Pig Iron 129



TABLE OF CONTENTS



SECTION III. A BRIEF OUTLINE OF THE PROCESS AND EQUIP-
MENT FOR THE MANUFACTURE OF PIG IRON:

1. Trend of Modern Improvements 130

2. Essentials of the Process 130

3. Essential Equipment 130

SECTION IV. CONSTRUCTION OF THE BLAST FURNACE PROPER:

1. The Gross Features of the Furnace Proper 131

2. The Foundation 131

3. The Hearth or Crucible 132

4. The Bottom 132

5. Tapping Hole 132

6. Cinder Notches 134

7. Tuyeres 134

8. Tuyere Connections 134

9. Boshes 135

10. Mantle 136

11. Shaft, or Stack, and In-Walls 136

a. Thick Wall Type 136

i. The furnace Lines and Bosh Angles 136

b. Intermediate, or Semi-Thin, Wall Type 137

c. Thin Walled Type 137

d. Furnace Linings 137

12. Water Trough 139

13. Tops 139

a. Stock Distributor 140

b. Hoisting Appliances 140

c. Top Openings 140

d. General Consideration for Top Construction. . 141

14. Runners 141

SECTION V. BLAST FURNACE ACCESSORIES:

1. The Stoves 142

a. Stove Burners and Valves 143

b. Other Stove Openings 143

c. Stove Linings 145

2. Dust Catcher and Gas Mains 146

3. Arrangement of Furnaces and Cleaning Plant at

Duquesne 146

a. Primary Division 148

i. Methods of Scrubbing the Gas 148

ii. The Fans 149

iii. Water Separator 149

b. The Secondary Division 149

SECTION VI. EQUIPMENT FOR HANDLING RAW AND FINISHED

MATERIAL-
1. The Boiler House, Power Plant, Pumping Station,

Blowing Engines, etc 150



TABLE OF CONTENTS xvii



SECTION VI. Continued.

2. Dry Blast 150

3. Cold and Hot Blast Mains 150

4. Appliances for Handling Ores, Coke and Stone 150

5. Stock House Equipment 151

6. Disposal Equipment for the Iron 152

7. Equipment for Slag Disposal 152

SECTION VII. OPERATING THE FURNACE:

1. Blowing In 152

2. Drying 152

3. Filling 153

4. Lighting 153

5. Heating the Bottom 154

6. The Heating of the Stoves 154

7. Tapping 154

8. Care of Runners 155

9. Sampling the Iron 155

10. Tapping Slag 156

11. Changing Stoves 156

12. Charging the Furnace 156

13. Some Irregularities of Furnace Operation 157

a. Slips 157

b. Scaffolding 158

c. Chimneying and Hot Spots 158

d. Loss of Tuyeres and Chilled Hearth 158

14. Uncertainties and Variables in Furnace Control 158

15. Banking 159

16. Blowing Out. 159

SECTION VIII. THE BLAST FURNACE BURDEN:

1 . Burdening the Furnace 159

a. Outline of a Method for Solving a Burdening

Problem 161 '

b. The Burden Sheet 161

2. Table 27. Analysis of Raw Materials Used in the

Blast Furnace 160

SECTION IX. CHEMISTRY OF THE PROCESS:

1. Methods of Investigating the Reactions of the Blast

Furnace 163

2. The Functions of Oxygen and Carbon 163

3. Behavior of Nitrogen in the Furnace 165

4. Action of Phosphorus in the Furnace 165

5. Disposition of Sulphur in the Furnace 165

6. Behavior of Silicon 165

7. Action of Calcium and Magnesium . . . . : 166

8. Action of Aluminum. . 166



TABLE OF CONTENTS



SECTION IX. Continued.

9. Action of Less Abundant Elements 166

10. The Reactions Within the Furnace 167

11. Tracing the Materials Through the Furnace 170

12. Conditions Affecting the Amount of Silicon and

Sulphur in the Metal 171

CHAPTER VII. The Bessemer Process of Manufacturing Steel.

SECTION I. THE CLASSIFICATION OF FERROUS PRODUCTS:

1. Introductory 172

2. Pig Iron and Cast Iron , 172

3. Malleable Cast Iron 172

4. Wrought Iron 173

5. Steel 173

6. Methods of Making Steel 174

7. General Principles of the Methods of Purifying

Pig Iron 175

SECTION II. PRINCIPLES AND HISTORY OF THE BESSEMER
PROCESS:

1. Principles of the Process 175

2. Some Incidents Connected with the Early History

of the Process ' 176

3. Importance of Manganese 176

4. Thomas and Gilchrist Process 177

5. Other Improvements 177

6. Plan of Study 177

SECTION III. EQUIPMENT AND ARRANGEMENT OF THE EDGAR
THOMSON PLANT:

1. The Converter House 177

2. The Larger Accessories 179

a. The Cupolas 179

b. Charging the Cupola 180

c. The Blast 180

d. The Mixers, 181

i. Importance of the Mixer 181

e. The Stripper 181

f. The Casting Equipment 182

i. The Ingot Moulds 182

SECTION IV. CONVERTER CONSTRUCTION AND REPAIRS:

1. General Features Pertaining to Converters 183

2. Parts of Converter 183

a. Lining of the Converter 184

b. The Bottom 185

i. Relining the Bottom 185



TABLE OF CONTENTS



SECTION V. THE CONVERTER IN OPERATION PURIFYING
THE METAL:

1. Charging the Vessel 187

2. The Blow 187

3. Controlling the Blow 188

4. The End of the Blow \ 189

SECTION VI. FINISHING OPERATIONS CONVERTING THE

PURIFIED METAL INTO STEEL:

1. Deoxidation and Recarburization 190

2. Loss of Recarburizer and Deoxidizer 191

3. Examples of Recarburizing 191

4. Ladle Reaction 191

5. Teeming 192

6. Sampling the Steel for Chemical Analyses 192

SECTION VII. CHEMISTRY OF THE PROCESS:

1. The Order of Elimination of the Elements 193

2. The Laws and Conditions Governing the Reactions

in the Converter 193

3. Reactions of the First Period 194

4. Reactions of the Second Period 195

5. Chemistry of Recarburizing and Deoxidizing 196

CHAPTER VIII. The Basic Open Hearth Process.

SECTION I. SOME GENERAL FEATURES OF THE SIEMENS

PROCESS:

1. Early History of the Process 198

2. Principles of Siemens Pig and Ore Process 199

3. Advantages of the Process 199

4. Mechanical Changes and Improvements in Siemen's

Process 200

5. Metallurgical Improvements 200

6. The Process for the Pittsburgh District 201

SECTION II. EQUIPMENT FOR A MODERN BASIC OPEN

HEARTH PLANT:

1. The Modern Plant 202

2. Calcining Plant 202

3. Fuels 203

4. Fuel Consumption 203

5. Hot Metal Mixer 204

6. Spiegel Cupolas 204

7. The Steel Ladles 204

8. The Stripper 205

9. Moulds 205

10. The Charging Machine 206

11. Charging Boxes 207

12. Stock Yard 207

13. Arrangement of the Plant 207



TABLE OF CONTENTS



SECTION III. CHIEF FEATURES OF BASIC OPEN HEARTH
CONSTRUCTION:

1. Parts of the Open Hearth Furnace and Their

Arrangement 209

2. The Furnace Proper 209

a. The Hearth 210

b. The Walls 210

c. The Roof 211

d. The Bulk Heads 211

3. The Ports 211

4. The Up-and-Down-Takes 211

a. Arrangement of Up-and-Down Takes for
Natural Gas, Coke Oven Gas, Powdered

Coal and Tar 212

5. Slag Pockets 212

6. Regenerators for Producer Gas 212

7. Regenerators for Natural and Coke Oven Gases. . . . 216

8. Regenerators for Powdered Coal 217

9. Flues and Valves 217

10. The Stack 217

SECTION IV. OPERATION OF A BASIC OPEN HEARTH-
PURIFYING THE METAL:

1. Furnace Attendants and Their Duties 218

2. Preparation. of the Furnace for its First Charge. . . . 218

3. Charging 219

a. The Order of Charging Raw Materials 220

4. Melting Down the Charge 220

5. The Addition of the Hot Metal 221

6. The Purification Periods 221

a. The Ore Boil 222

i. The Run off 222

b. The Lime Boil 223

c. The Working Period. ,...' 223

i. Methods of Working the Heat 223

ii. Testing for Carbon 224

iii. Control of Carbon and Temperature . . . 224

iv. Judging the Temperature of the Bath. . . 225

7. Tapping 225

SECTION V. FINISHING THE HEAT MAKING STEEL FROM
THE PURIFIED METAL:

1. Methods of Finishing the Steel 226

2. Some Features that Make the Finishing of the Steel

Difficult 227

3. Teeming 228

4. Sampling 229



TABLE OF CONTENTS xxi

SECTION VI. KEEPING THE FURNACE IN REPAIR:

1. Preparation of the Furnace for the Next Charge 229

2. Furnace Troubles 230

3. Repair Materials 231

a. Dolomite 231

b. Magnesite 231

c. Chrome Ore 231 .

SECTION VII. CHEMISTRY OF THE BASIC PROCESS:

1. Some of the Principles and Conditions Involved.,. 232

2. Properties of Iron and Its Oxides 232

a. The Importance of Ferrous Oxide, FeO, in the
Part Played by the Oxides of Iron in the

Process 233

3. Properties of Silicon and Its Oxide, Silica 234

4. Properties of Manganese and Its Oxides 235

5. Sulphur and Its Oxides 236

a. Sulphur from the Fuel 237

6. Phosphorus and Its Oxides 237

7. Carbon and Its Oxides 238

a. The Action of the Limestone 239

b. Effect of Carbon Elimination on Slag

Composition 239

8. The Order of Elimination 239

a. Factors Opposing this Order of Elimination 240

9. Resume 241

CHAPTER IX. Manufacture of Steel in Electric Furnaces.

SECTION I. INTRODUCTORY:

1. The Plan of Study 243

2. Force, Work, Energy and Potential 243

3. Power 240

4. Transmission of Energy 244

5. Electromotive Force (E. M. F.) 246

SECTION II. THE DEVELOPMENT OP ELECTROMOTIVE FORCES

OR "GENERATION OF CURRENT:"

1. Methods for Setting Up Electric Currents 246

2. Magnetism , 246

a. Magnets and Magnetic Substances 247

b. Magnetic Fields and Electric Currents 248

3. Electromagnetic Induction 249

a. Laws of Electromagnetic Induction 250

b. The Dynamo 250

SECTION III. KINDS OF CURRENT: