Hydrostatic and Hybrid Bearing Design (eBook)

Front Cover 1
Hydrostatic and Hybrid Bearing Design 4
Copyright Page 5
Table of Contents 6
Preface 10
Usual meaning of symbols 12
Chapter One. Application of hydrostatic bearings 16
1.1 Introduction 16
1.2 What is a hydrostatic bearing? 16
1.3 When should a hydrostatic bearing be employed? 21
1.4 Bearing selection 24
1.5 Materials selection 34
Chapter Two. Basic theory governing pressure, flow and bearing forces 36
2.1 Viscosity 36
2.2 Density: consistent units 38
2.3 Compressibility 38
2.4 Viscous flow between parallel plates 38
2.5 Combined pressure and velocity-induced viscous flow in a two-dimensional non-parallel film 41
2.6 Flow through restrictors 42
2.7 Recess pressure and pressure ratio 44
2.8 Bearing load 45
2.9 Use of dimensionless data 48
Chapter Three. Power, temperature rise and minimum power 50
3.1 Pumping power 50
3.2 Friction power 50
3.3 Total power and power ratio 51
3.4 Temperature rise 52
3.5 Optimization 53
3.6 Minimum power for low-speed bearings 
53 
3.7 Minimum power for high-speed recessed bearings 54
3.8 Optimization of plain hybrid bearings 60
Chapter Four. Thrust pads: load and flow rate 61
4.1 Derivation of load and flow data for plane thrust pads 61
4.2 Circular pad data 62
4.3 Square pad data 64
4.4 Rectangular pad data 66
4.5 Annular recess circular pad data 66
4.6 Conical pad data 69
4.7 Spherical pad data 73
4.8 Multi-recess circular pad data 75
4.9 Multi-recess rectangular pad data 77
4.10 Data for rectangular pad with radiussed recess corners 80
4.11 Data for any shape with thin constant land width 80
4.12 Annular multi-recess pad data 81
Chapter Five. Circuit design, flow control, load and stiffness 84
5.1 Definition of bearing film stiffness 84
5.2 Circuit design and sealing 86
5.3 Load and stiffness of a capillary-controlled pad 88
5.4 Flow control devices 91
5.5 General stiffness law for a bearing pad 101
Chapter Six. The basis of the design procedures and selection of tolerances 104
6.1 Zero or low-speed bearings 104
6.2 Relationships affecting tolerances 106
6.3 High-speed bearings 107
6.4 BS 4500: Specification for ISO limits and fits 109
Chapter Seven. Plane hydrostatic bearings 112
7.1 Use of the design charts 112
7.2 Choice of land width 113
7.3 Flow rate 113
7.4 Load 114
7.5 Stiffness 114
7.6 Single plane bearings 114
7.7 Double plane bearings having equal opposed pads 121
7.8 Double plane bearings having unequal opposed pads 125
7.9 Complex arrangements of plane pads (capillary compensation) 131
Chapter Eight. Partial hydrostatic journal bearings 137
8.1 Recessed partial journal bearings 137
8.2 Grooved partial journal bearings 138
Chapter Nine. Recessed cylindrical hydrostatic journal bearings 147
9.1 Introduction 147
9.2 Flow in hydrostatic journal bearings 149
9.3 Load 153
9.4 Power and temperature rise 157
9.5 Land width ratios and design pressure ratio 158
9.6 Selection of tolerances 158
9.7 Selection of supply pressure, viscosity and clearance 158
9.8 Bearing film stiffness 162
Chapter Ten. Hydrostatic and hybrid plain journal bearings 169
10.1 Introduction 169
10.2 Selection of bearing configuration 170
10.3 Power ratio 172
10.4 Design pressure ratio 172
10.5 Clearance and clearance limits 172
10.6 Load 173
10.7 Flow rate 177
10.8 Power and temperature rise 178
Chapter Eleven. Combined journal and thrust bearings (the Yates bearing) 182
11.1 Introduction 182
11.2 Principle of operation 184
11.3 Basic parameters 184
11.4 Design procedure 186
Chapter Twelve. Conical journal bearings 194
12.1 Introduction 194
12.2 Basic parameters 196
12.3 Design procedure 197
Chapter Thirteen. Spherical bearings 202
13.1 Introduction 202
13.2 Basic parameters 203
13.3 Central recess bearing 204
13.4 Annular recess bearing 205
13.5 Multi-recess bearings 206
Chapter Fourteen. Dynamics 210
14.1 Introduction 210
14.2 Static loading 211
14.3 Dynamic loading 211
14.4 Squeeze damping 212
14.5 Compressibility 214
14.6 Dynamic model of a thrust pad 214
14.7 Thrust pad with thin lands 217
14.8 Journal bearings 220
Chapter Fifteen. Experimental methods and testing 230
15.1 Introduction 230
15.2 Flat pad rig 231
15.3 Cylindrical journal bearing rig 233
Appendix A: Design procedures and examples 238
Single plane pads 239
Equal opposed pads 241
Unequal opposed pads 243
Journal bearings 245
Complex arrangements of plane pads 247
Capillary restrictor 249
Appendix B: References and design bibliography 251
B1 References 251
B2 Design bibliography 252
Index 254