1 Contents

of tools. Tool grinding, Movements of cutter and workpiece. The requirements of a machine tool. Summary.

16 Marking-out and Location of Work Methods of marking out. Accuracy of marking out. Coordinates. Jigs and fixtures. Summary.

17 Plane Surfaces 219 Introduction to plane surfaces. Straight edges. The try-square.

Y 3 Summary.

18 Lathes 225 Main features of a centre lathe. Types of lathe work. Chucks. 'ace-plates. Steady rests. Setting of tools. Speeds, feeds, and depths 'cut. Lathe operations. Taper turning and boring. Screw cutting. ??.tan and turret lathes. Lathe alignments. Care of lathes. :ty in the machine shop. Summary.

'Iling Machines i of drilling machines. Operations and cutters. b ?n of workpieces. Drilling machine alignments. Summary.

i aping, Slotting, and Planing Machines 262 'ping machine. The slotting machine. Planing machines. groove. Summary. ding Machines 282

milling machines. Types of milling cutters. Up-cut milling ,own-cut milling. Straddle milling and gang milling.

"kpiece location and holding. Milling machine alignments. mary.

r -- II

2 2 Grinding, Honing, and Lapping Grinding. Honing. Lapping. Summary.

Contents

23 Engineering Measurement 314 Standards of length. The measurement of length. Comparators. The measurement of angles. Summary.

2 4 Dimensional Control 339 Tolerances and limits of size. Fits. Systems of limits and fits. British Standard 4500, 1969: specification for I S 0 limits and fits. Dimensional control. Limit gauging. Summary.

25 Machine-shop Process Planning 355 Process sheets and choice of planning method to suit production volume. Choice of location points. Planning method. Specimen operation layouts. Summary.

26 Floor-tefloor Times 370 Introduction. Calculation of times for lathe work. Calculation of times for drilling machine work. Calculation of times for milling machine work. Calculation of times for reciprocating machine work. Calculation of times for cylindrical grinding. Calculation of times for surface grinding. Examples. Summary.

Bibliography

Index

Abrasive, 297,298 grain size of, 299

Acid steels, 27 Adhesive joining, 150 Adjustable reamer, 255 Admiralty brass, 61 Admiralty gunmetal, 62 Air-hardening steels, 52 Airy points, 3 16 Alignment: of drilling machines,

of grinding machines, 306 of lathes, 245 of milling machines, 291 of planing machines, 277 of shaping machines, 268 of slotting machines, 274

Alloy, 2 Alloy cast irons, 24 Alloy steels, 49 Aluminium, 56, 66 Aluminium alloys, 58

casting, 59 corrosion protection of, 59 heat-treatment of, 59 wrought, 59

Aluminium bronzes, 63 Angular measurement, 327

by balls and rollers, 333 by sine bar, 328 by spirit level, 330 by vernier protractor, 327

Annealing, 99 of aluminium alloys, 59

of brasses, 6 1 of copper, 5 7 of steels, 36

Anodising, 59 Antimony, 64, 65 Approach angle, 176 Arc of contact when grinding, 301 Arc-welding, 142 Area of contact when grinding, 301

258 Arithmetic progression, 193, 194 Arsenic in copper, 5 7 Austenite, 33 Austenitic steels, 53

Backing sand, 106 Balancing of grinding wheel, 304 Bar material, 93 Bar standard, 3 15 Base of an alloy, 2 Base-metal thermocouple, 80 Basic steels, 27 Bearing metals, 64 Bed-type milling machine, 284 Bedding, 220 Bend tests, 10 Bending operation, 153 Beryllium, 56, 65 Bessemer process, 28 Bilateral limits, 340 Blackheart malleable cast iron, 22 Blanking operation, 152 Blast furnace, 16

metal, 16

Block level, 330 Blow forming, 169 Bolster for press set, 156 Bond for abrasive, 297,299 Brasses, 60, 64 Brazing, 150 Bright drawn bar, 93 Brinell hardness test, 11 British Standards Institution, 7 Brittleness, 5 Bronzes, 62 Built-up edge, 174 Bunsen burner, 72 Button boring, 2 11

Capstan lathe, 244 Carbon, 16

in cast iron, 20 in steels, 26

Carbon electrode, 142 Carburising, 42

gases, 70 Cartridge brass, 61 Case-hardening, 42

steels, 5 1 Cast iron, 16

alloy, 24 blackheart malleable, 22 grey, 20 high-duty, 23 inoculation of, 23 malleabilising of, 22 mottled, 2 1 pearlitic, 22-3 production of, 19 spheroidal graphite, 23 structure of, 20, 22-3 white, 20 whiteheart malleable, 22

Casting, 92 defects in, 123 methods: centrifugal-, 123

die., 126 investment-, 129 sand-, 105

of plastics, 169 of phosphor bronze, 62

Celluloid, 163 Cellulose plastics, 163 Cemented-carbide tool material, 185 Cementite, 17, 26 Centre lathe, 225 Centre punch, 204 Centrifugal-casting, 123 Chaplet, 11 1 C h q y test, 12 Chasing dial, 243 Chasing tool, 243 Chill, 21 Chip formation: built-up edge, 174

continuous, 173 discontinuous, 174

Choice: of datum points for machining, 358

of location features for machining, 36 1

of material, 1 of pyrometer, 90

Chromium, 56 in alloy steels, 50 in cast iron, 24

Chucks, 23 1 Clamping: of milling fixtures, 2 17

of workpiece, 2 15 Clapper box, 264 Classification: of grinding wheels,

304 of materials, 1

Clearance angle, 172, 173 Clearance fit, 34 1 Cobalt-base tool alloys, 185 Coining, 101, l54 Cold-chamber die-casting, 128 Cold-extrusion, 101 Cold-heading, 102 Cold-rolling, 99 Cold-short, 18 Cold-working processes, 92,98 Column drilling machines, 252 Comparators, 323

Compound gear train, 241 Compound slide rest, 229 Compression-moulding process, 167 Continuous chio formation. 173 Continuous furnace, 75 Contraction rule, 105 Convertor processes for steel

production, 28 Coordinates, 208 Cope, 107 Copper, 56

in alloy cast irons, 24 Copper alloys, 57 Copper-based alloys, 60 Copying, 191 Core: for sand-casting, 109

stripping, 118 Core print, 110 Corrosion-resisting steels, 53 Counterboring, 256 Countersinking, 257 Cracking of steel during heat-

treatment, 39 Creep, 13

testing, 13 Crimping, 154 Critical cooling rate for steels, 38 Critical points for steels, 33 Cropping, l52 Cross-wind, 226 Cupola, 19 Curing of plastics, 162 Cutters: for planing machines, 272

for slotting machines, 272 Cutting fluids, 182 Cutting-tool: forces acting on, 181

materials, 183 shape, 175

Cyanide process, 44 Cylindrical square, 222

Datum points, 35 8 Decarburisation of steel, 43 Deep drawing, 100, 153 Defects in castings, 123

Degrees of freedom, 2 1 4 15 Depth gauge: micrometer, 323

vernier, 32 1 Design: for die-casting, 129

for heat-treatment, 41 Deviations from size, 345 Dial-indicator, 324

uses of, 325 Diamond tool material, 186 Die-casting, 126

design for, 129 Die-forging, 98 Die-sets, 156 Dimensional control, 339,347 Dimensioning to improve accuracy,

?All - .- Disappearing-filament pyrometer, 88 Discontinuous chio formation. 174 Dividing chuck, 290 Dividing head, 290 Double-acting press, 154 Down-cut milling, 288 Drag, l06 Drawback, 1 13 Drawing, 93

press tool set for, 159 Drawing-down, 97 Dressing of grinding wheel, 304 Drill: spade, 177

twist, 177 Drilling: jig, 2 15

machine, 252 alignment of, 258 column, 252 portable, 252 radial-arm, 253 sensitive, 252

operations, 254 reaming, and boring in a lathe, 236 speeds and feeds, 255

Drop-stamping, 98 Ductility, 4, 9, 10

Elastic limit, 2, 10 Elasticity, 2

-T

Index

Electric-arc furnace, 19, 30 Electric-arc welding, 142 Electric furnace, 76 Electric processes for steel

production, 30 Electrical re&ance thermometer, 83 Embossing, 101, 154 End bars, 3 15 End standard, 3 15 Ending up, 236 End-milling cutters, 286 Engineer's block level, 330 Engineer's rule, 3 18 Epoxy resins, 166 Equilibrium diagram for steels, 35 Eutectic, 65 External grinding, 305 Extensometer, 7 Extruded sections, 95 Extrusion, 97 Extrusiou-moulding of plastics, 168

Faceplate, 232 Facing sand, 106 Factory inspectors, 249 Fastening, 133 Fatigue, 12

testing, 12 Feed: of cutting tool, 177

for drilling operations, 255 Feeding of strip material in

presswork, 155 Feeler gauges, 3 17

accuracy of, 3 17 Ferrite, 17, 26, 33 Ferrous materials, 1 Fits, 341 Fixtures, 2 13

milling, 2 16, 2 17, 29 1 Flame-cutting, 148 Flame-hardening, 42.45 Flash, 98 Flash-butt welding, 136 Flask, 106

Floor moulding, 112 Floor-to-floor times, 370 Fluorine plastics, 165 Folded joint, 134 Follow-on pierce-and-blank press-

tool set, 156, 158 Forced air-circulation furnace, 77 Forge-welding, 135 Forging, 95, 97 Forging-dies, 98 Form-milling cutters, 287 Form relief, 189 Fonn-tool manufacture, 190 Forming-cutting operations, 188 Forming: of plastics, 168

operations in presswork, 153 Fundamental deviations from size,

345 Fusible cones, 79 Fusion-welding, 138

Gang milling, 289 Gap gauge, 349 Gas-fired furnaces, 69 Gas-torch welding, 142 Gas-welding, 146 Gauge blocks, 3 16 Gauge length, 7 Gauging of shafts, 349 Gearbox, 199 Gear train: compound, 241

simple, 240 Generating, l 9 1 Generation of try-squares, 223 Geometric progression, 194, 195 Glazing of grinding wheel, 298 'Go' gauge, 348 Gooseneck system of die-casting, 127 Grades of tolerance, 344 Grain: fibre, 92

flow, 92 growth, 43 size of abrasive, 299

Graphite, 17, 20 Graphitisation, 2 1

Gravity die-casting, 126 Grey iron, 20 Grinding, 296

arc of contact, 30 1 area of contact, 301 external, 305 internal, 305 surface, 306

Grinding machine: alignments, 306 movements, 305

Grinding wheel: balancing, 304 bond, 299 classification, 304 cutting action, 297 dressing, 304 end-cutting, 297 grade, 300 mounting, 304 peripheral-cutting, 296 selection, 303 self-sharpening, 298 speed, 302 structure, 297, 300 tming, 304 work speed, 302

Gunmetals, 62

Hafnium, 56, 66 Hand lapping, 309 Hardening: of high speed steel, 73

of steels, 38, 42 Hardness, 5

tests, 11 Heat-resisting steels, 54 Heat-treatment, 69

of aluminium alloys, 59 of cast iron, 2 1 of steels, 33, 36 furnace, 69

Hermaphrodite compasses, 204 High-duty cast irons, 23

Hone, 306 abrasive, 306

Honing, 296, 306 cutting action, 308 machine, 309

Hooke's law, 3, 10 Horizontal milling machine, 282 Hot-chamber die-casting, 127 Hot-rolling, 95 Hot-short, 18 Hot-working, 92,95

Impact extrusion, 101 Impact tests, 11 Imperial standard yard, 3 15 Impurities in steel, 17, 26 Inconel, 64 Indicating gauges, 35 1 Induction furnace, 3 1 Induction hardening, 42,45, 46 Induction heating, 77 Ingot, 92 Injection-moulding of plastics, 167 Inoculation of cast irons, 23 Inserted cutter blades, 185 Inside micrometer, 323 Inspection of welds, 149 Interchangeability, 314,339 Interference fit, 342 Internal grinding, 305 Investigations into metal cutting, 181 Investment-casting, 129 Izod test, 12

Jennies, 204 Jig, 213

for drilling, 2 15 Jig-boring machine, 209, 210 Joining: mechanical methods, 133

metallurgical methods, 134 plastics, 170

High-frequency induction furnace, 3 1 K~~~~~~ as length standard, High-speed steels, 50, 184 High-tensile steels, 52 Laminates, 166 Hole-based system of limits, 342 Laminating of plastics, 170

Index

Landing groove, 278 Lapping, 296, 309 Lathe: alignments, 245

bed, 226 care of, 248 chucks, 23 1 compound slide rest, 229 faceplate, 232 feedshaft, 228 headstock, 226 spindle nose, 228 steady rest, 233 tool setting, 233 types: centre, 225

capstan, 244 turret, 244

Lathework, 299 effect: of cutting fluid, 235

of material, 235 of surface finish, 235 of type of lathe, 235 of type of operation, 235 of type of work, 234

speeds, feeds, and depths of

Lead, 57,62 Lead-base bearing alloy, 64 Length gauge, 349 Length measurement, 3 18 Level-comparator, 332 Limit gauges, 348

gap, 349 indicating, 35 1 length, 349 plug, 348 receiver, 350 recess, 349 ring, 349 rod, 348 screw-thread, 349 stepped taper, 350 taper, 350 thickness, 349

Limit: of elasticity, 4 of proportionality, 4

Limits and fits, systems of, 342 Limits of sizes, 339 Line standards, 3 15 Lintz-Donawitz process, 29 Loading of grinding wheel, 298 Loam moulding, 114 Location: for drilling, 258

features, 36 1 fmm holes, 362 of milling fixture, 2 17 of workpiece, 2 14

Liquid mercury thermometers, 79

Machine lapping, 309,3 10 Machine-tool: gearboxes, 192

requirements, 192 Machine vice, 289 Machining: allowance, 204

of plastics, 170 Magnesium 57,66

alloys, 63 Malleabilising of cast irons, 22 Malleability, 5

cuts, Manganese, 27 234 in alloy steels, 50

Manganese bronze, 61 Marking-out, 204

accuracy of, 208 Martensite, 38 Materials: classification of, 1

for cutting-tools, 183 Measurement: of angles, 327

by balls and rollers, 333 by sine bar, 328 by spirit level, 330 by vernier protractor, 327

of length, 3 18 Mechanical joining methods, 133 Mer, 161 Metal-cutting investigations, 181 Metal electrode, 142 Metal joining: adhesives, 150

brazing, 150 soldering, 150 welding, 135

Metre, 3 15 Micrometer, 321

depth gauge, 323 inside, 323

Microstructure, 17 Milling, 282

straddle and gang, 289 up-cut and down-cut, 288

Milling cutter, 180,285 end cutters, 286 form cutters, 287 roller cutters, 285 side-and-face, 286

Milling fixture, 216, 217, 291 Milling machine, 282

alignments, 29 1 bed-type, 284 horizontal, 282, 283 knee-and-column, 282 universal, 284 vertical, 282, 283

Modulus of elasticity, 3 Molybdenum: in alloy steels, 50

in cast iron, 24 Monel, 63 Monomer, 16 1 Mottled irons, 2 1 Mould, shell, 122 Moulding, 106

floor, 1 12 loam, 1 l 4 odd-side, 1 12 of plastics, l67 plate, 1 19 sand, 105

Moulding box, 106 Moulding Bask, 106 Moulding sands, 120

essential properties of, 120 Mounting of grinding wheel, 304 Movements: of cutter and workpiece,

188 of grinding machine, 305

Mume furnace, 7 1 Muntz metal, 61

Naval brass, 6 1 Negative rake, 173 Neutral atmosphere, 70 'New' metals, 65 Nickel, 57, 62

in cast iron, 24 in steels, SO

Nickel alloys, 63 Nickel bronzes, 62 Nickel-chromium alloys, 64 Nickelxopper alloys, 63 Nickel-iron alloys, 63 Nickel silver, 62 Nimocast alloys, 64 Nimonic alloys, 64 Niobium, 66 Nitriding, 42, 44

steels, 5 1 Nitrocellulose, 163 Non-ferrous metals, 1, 56 N.P.L. level-comparator, 332 Normalising, 26.37 'NOT Go'gauge, 348 Nylon, 165

Observed times, 370 Odd-side moulding, 1 I2 Open-hearth process, 29 Operation layouts, 364 Operation sheet for production, 357 Operations list: for production shop,

357 for tool-room, 356

Optical pyrometer, 88 Oxidising atmosphere, 70

Parting sand, 107 Pattern: for sand casting, 105

skeleton, 114 Pearlite, 17, 26

sorbitic, 39 troostitic, 39

Pearlitic: cast iron, 23 malleable cast iron, 22

Percentage elongation after fracture, 9

Index

percentage reduction of area, 9 Peripheral-cutting milling cutter, 1 Phenolic plastics, 166 Phosphor bronze, 62,64 Phosphorus, 17,62

in steels, 27 Piercing, 152 Pig iron, 16,27 Plain carbon tool steels, 184 Plane surfaces, 2 19 Planing machine, 275

alignment, 277 tools, 277

Planning method, 355,362 Plasticity, 5 Plastics materials, 16 1

cellulose, 163 condensation polymers, 165 curing of, 162 fluorine, 165 laminates, 166 manipulation methods, 167

casting, 169 forming and pressing, 168 jo in i i , 170 laminating, 170 machining, 170 moulding, 167

phenolic, 166 polyesters, 165-6 thermosetting, 162, 166 thermosoftening, 16 1, 163 vinyl, 163

Plate metal, 95 Plate moulding, 119 Plate welds, 140 Plug gauge, 348 Plumber's solder, 65 Polar coordinates, 208 Polyamides, 165 Polyesters, 165 Polymer, 161 Polystyrene, 164, 165 PolytetraAuoroethylene (PTF~), Polythene, 164

Polyvinyl chloride (PVC), 164, 165 Portable drilling machines, 252 Presses, 154

capacity, 155 double-acting, 154 single-acting, 154 triple-acting, 155

Pressing, 99 of plastics, 168

Press tools, 152 Pressure die-casting, l26 Pressure-welding, l38 Presswork, 152 Process planning, 355

sheets, 35 5 Profile location, 36 1 Progressive error, 321 Projection spot-weldiag, 138 Proof stress, 9, 10 Properties of metals and alloys, 2 ~ u d d l i i g furnace, 18 Pure metals, 1 Pyrometry, 78

pyrometers, 79-90 choice of, 90

Quality control, 347 Quenching: medium, 39

of steel, 3 6 Quick-return action, 265

Radial-arm drilling machine, 253 Radiation pyrometer, 85 Rake angle, 172 Rare-metal thermo~~uple, 80 Rating of effort, 370 Reaming operation, 255 Receiver gauges, 350 Recess gauge, 349 Reciprocating machine tools, 262 Recorders, 83 ~ectangular coordinates, 208 Red hardness, 184 ~educing atmosphere, 70 Relieving tool, 273

Index

Research tests, 7 Resistance-welding, 135 Ring gauge, 349 Riser, 107, 108 Riveting, 134 Rockwell hardness test, 11 Rod gauge, 348 Roll arrangements in rolling mill, 96 Rolled sections, 94 Roller cutters, 285 Rotary furnace, 19, 20 Rotary milling table, 289 Routine tests, 7 Rule, 3 18 Runner, 107, 108

Safety: factor, 9 in the machine shop, 248

Salt-bath, 43 furnace, 76

Sand: composition, 12 1 moulding, 105, 120 testing of, 122 types of, 106

Sand-casting, l 0 5 Scale formation, 70 Screw-cutting, 239 Scrihing block, 204 Seam-welding, 138 Selection of joining method, 13 3 Self-sharpening action of grinding

wheel, 298 Sensitive drilling machine, 252 Setting down, 97 Setting of lathe tools, 233 Shaft-based system of limits, 342 Shaping machine, 262

alignments, 268 operations, 267

Shear on press tools, 156 Sheet material, 94 Shell end mill, 180 Shell moulds, 122 Shock resistance, I I Side-and-face milling.cutters, 286

Silicon, 17, 2 1, 26 Silver, 56, 57 Simple gear train, 240 Sine-bar, 328

applications of, 329 Single-acting presses, 154 Single-point cutting tool, 177 Sintered oxide tool materials, 185 Six degrees of freedom, 2 l4 ,2 15 Skeleton patterns, 114 Slip gauges. 3 16

applications of, 3 17 care of, 3 17

Slotting cutters, 272 Slotting machine, 270

alignments, 274 operations, 274

Solder, 65 Soldering, l50 Solid solution, 17, 33 Sorbite, 40

sorbitic pearlite, 39 Spade drill, 177 Speed: for drilling, 255

progressions, 192 Spheroidal graphite cast iron, 23 Spheroidising of steel, 37 Spinning, 102 Spirit level, 330 Split patterns, 109 Spot-welding, l37 Spray steelmaking, 3 1 Spring-hack allowance when bending,

153 Standards of length, 3 14

bar, 3 15 end,315 line, 315

Steady rests, 233 Steel, 16, 26

acid, 27 air-hardening, 52 alloy, 49 austenitic, 53 basic, 27

Index

Steel--(conrd.) carburising of, 42 case-hardening of, 42 corrosion-resisting, 53 cracking of, 39 critical cooling rate of, 38 hardening of, 38.42 heat-resisting, 54 heat-treatment, 33, 36 high-speed, 50, 184

hardening of, 73 high-tensile, 52 impurities in, 17, 26 nitriding of, 5 1 plain carbon tool, 184 quenching of, 36 spheroidising of, 37 structure of, 27, 35, 44 surface-hardening of, 42 wear-resisting, 53

Steelmaking processes, 27 Stepped taper gauge, 350 Straddle milling, 289 Straight edges, 221 Strain, 3 Statistical quality control, 347 Stress, 3 Stripper plate, 15 6 Structure: of carburised steel, 44

of casehardened steel, 44 of cast irons, 20,22,23 of grinding wheel, 300 of steels, 27, 35 of wrought iron, 18

Subcritical annealing, 37 Sulphur, 18.27 Surface grinding, 305 Surface-hardening of steel, 42 Surface plate, 2 19

Tap, 257 tapping, 257

Taper turning and boring, 237 by combining feeds, 239 by setting compound rest, 238

by setting over the tailstock, 237 by turning attachment, 238

Taper measurement, 333 Tellurium in copper, 57 Temper brittleness, 50, 52 Tempering, 40 Tenacity, 2 Tensile strength, 9

test, 7,9 Testing: of metals, 7

of sand, 122 Thermocouple, 80 Themo-electric pyrometer, 79 Thermometers, 79 Thermosetting plastics, 162, 166 Thermosoftening plastics, 16 1, 163 Thickness gauge, 349 Times: for cylindrical grinding, 375

for drilling-machine work, 372 for lathework, 371 for milling-machine work, 373 for surface grinding, 376

Tin, 58 Tin-base bearing alloy, 64 Tin bronzes, 62 Tinman's solder, 65 Titanium, 58 Tolerances, 339 Tool: dynamometer, 18 1

grinding, 187 life, 182 materials, 183 storage and distribution, $86

Toolmaker's buttons, 2 11 Toolmaker's flats, 221 Toughness, 5, 11 Trail angle, 176 Transition fit, 342 Tricel, 163 Triple-acting presses, 155 Troostite, 40 Troostitic pearlite, 39 Truing of grinding wheel, 304 Try-square, 221 Tube drawing, 100

Index

Tube material, 95 Tungsten, 56

in high-speed steels, 50, 184 Turning between centres, 229 Turret lathes, 244 Twist drill, 177

Unilateral limits, 340 Universal milling machine, 284 Up-cut milling, 288 Upsetting, 97

Vacuum-forming ofplastics materials, 168

Vanadium, 56,66 Vapour-pressure thermometer, 79 Vee-bending press-tool set, 159 Vee-blocks, 206 Vee location, 36 1 Venting of sand moulds, 108 Vernier, 3 18

caliper, 320 depth gauge, 3 2 1 height gauge, 320 protractor, 327

Vertical milling machine, 282, 283 Vickers pyramid hardness test, 11 Vinyl plastics material; 163 Voids, 297

Waisting, 5 Wear-resisting steels, 53 Welding, 135

arc-welding, 142 Aash-butt welding, 136 forge-welding, 135 fusion-welding, 138 gas-welding, 146 inspection of welds, 149 pressure-welding, 138 projection spot welding, 138 resistance-welding, 135 seam welding, 138 spot welding, 137

Wheatstone bridge, 83 Wheel: glazing, 298

loading, 298 speed for grinding, 302

White iron, 20 Whiteheart malleable cast iron, 22 Whitworth, Sir Joseph, 219 Wire drawing, 100 Work-hardening, 92,93,99 Working, 18,92 Workpiece location, 2 14, 2 15

for drilling, 258 for milling, 289

Wrought: forms, 93 structure of, 92

Wrought iron, 16, 18 production of, 18

Yield point, 4, 9, 10 Young's modulus of elastidity, 3

Zinc, 58 Zirconium, 56,66

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