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Class Number: 122 Class Title: LIQUID HEATERS AND VAPORIZERS Subclass Subclass Number Title 1 R PLANTS 2 .Garbage 3 .Motor vehicle 1 A .Air heaters 1 B .Once through 1 C .Feed water heaters 4 R MISCELLANEOUS 4 A .Electric boiler 4 C .Water-cooled stoker 4 D .Catalyst 5 GAS-PRODUCER 5.51 AIR-INJECTED 5.52 .Combustion gas and vapor contact 6 R INDUSTRIAL 6.5 .Port 6.6 .Tuyeres 6.7 ..Forge 7 R .Waste heat 7 A ..Steel converter 7 B ..Additional burner 7 C ..Waste sulfite 7 D ..Carbon monoxide 8 .Water firebox 9 ..Water tube type 6 A .Water-cooled walls 6 B .Bosh plates 6 C .Skew arch coolers 10 FOR FLUID FUEL BURNER 11 ROTARY 12 ROTATABLY SUPPORTED 13.1 STAND BOILER 13.2 .Electric .Fire tube and water tube 16 ..Fluid fuel .Fire tube 17 ..Fluid fuel .Water tube ..Below boiler 18 ...Fluid fuel ..Casing 19 ...Fluid fuel 14 .Fluid fuel 15 .Solid fuel 20 R SUBSIDIARY 20 A .Subsidiary-heater firebox 20 B .Subsidiary-heater offtake flue 29 ANNULAR FIREBOX 30 MAGAZINE * INDIRECTLY HEATED .Separate fluid 32 ..Surface 33 ...Furnacee 34 ...Separator 31.1 INDIRECTLY HEATED SEPARATE INJECTED FLUID 31.2 .Submerged flame 35 ACCUMULATOR 36 AUXILIARY STEAM HEATER 37 COMPARTMENT .Auxiliary 38 ..Draft regulator 39 FILM 40 FLASHER 41 .Fluid fuel 42 FIRE AND WATER TUBE 43 .Fluid fuel 44.1 FIRE TUBE 44.2 .With baffle in flue 49 .Horizontal and vertical .Horizontal or inclined ..Water firebox 50 ...Flue 51 .Horizontal 52 ..Plural 53 ...Water tube ..Central firebox 54 ...Double outlet 55 ..Cylinder ..Depending fire tube 56 ...Rear of bridge wall ..Double water firebox 57 ...Alternate smoke return 58 R ..Drop water firebox 59 ...Circulation conduit ...Double 60 ....Alternate smoke return 61 ...Drop water baffle 62 ...Front and rear water baffle 63 ...Front water baffle 64 ...Interposed combustion chamber 65 ...Rear water baffle 66 ...Water coking chamber ...Water grate 67 ....Intermediate draft 68 ...Water tube ....Feed heater 69 .....Check-valved 70 ....Feeding air 71 ....Solid baffle 58 FB ...Fire box construction 72 ..Projecting into firebox 73 ...Drop water firebox ..Return and reverse 74 ...Drop water firebox 75 ..Return fire tube 76 ...Drop water firebox 77 ....Internal water tube ...Water firebox 78 ....Flue 79 ..Subjacent water arch 80 ..Subjacent fluee 81 ..Subjacent transverse fire tube ..Superjacent feed heater 82 ...In communication 83 ..Transverse diaphragm ..Two diameters 84 ...Great diameter over firebox 85 ...Small diameter over firebox 86 ....Water firebox 87 ..U-coupling 88 ..Upper drum ..Water arch 89 ...Rear of fire tube 90 ..Water firebox ...Firebox water heater 91 ....Trapped circuit 92 ...Magazine 93 ...Offset 94.1 ....Water tube type 95.1 ...Plural with common combustion chamber 95.2 ....Multiboilers 96 ...Superposed ...Water grate 97 ....Downdraft 98 ....Updraft ...Water tube 99 ....Straddle ...Water tube type 100 ....Interposed flue 101 ..Water smoke box ..Water tube ...Horizontal 102 ....Over bridge wall 103 ...Rear of fire tube ...Rearwardly declined 104 ....Over bridge wall ...Rearwardly inclined 105 ....Over bridge wall 106 ..Water wall 107 ...Drop water firebox 108 ...Subjacent water tube 109 .Inclined .Transverse 110 ..Horizontal boiler 111 ..Vertical boiler 112 ...Water firebox 113 ..Water tube 114 .Vertical 116 ..Central fire dome 117 ..Central magazine ..Circulation tube 118 ...Internal 119 ..Cylinder 120 ..Offset firebox 121 ..Return fire tube 122 ...Water firebox 123 ..Separate compartment 124 ..Side magazine 125 ..Top water chamberr 126 ..Water firebox 127 ...Annular 128 ...Central magazine ..Water grate 129 ...Downdraft 130 ..Water tube 131 ...Internal 132 ...Radial loop 133 ...Spur 115 ..Fluid fuel 134 .Volute 46 .Magazine .Flue 47 ..Horizontal 48 ..Vertical 45 .Fluid fuel 135.1 FLUE 135.2 .Alternative stack 135.3 .Sinusoidal flue 136 R .Horizontal 137 ..Plural 138 ...Water tube 139 ..Drop water firebox 140.1 ..Internal water tube 140.2 ...Having water tube in flue ...Longitudinal 141 ....Drop water firebox 142 ...Return fire tube 143 ...Spur 144 ...Subjacent firebox 145 ...Transverse 146 ....Drop water firebox 147 ....Return fire tube 148 ...Water firebox 149 ..Return fire tube 150 ...Rear water tube ...Water smoke box 151 ....Separate 152 ..Water grate in flue 153 ..Water tube 154 ...Over bridge wall 136 C ..Horizontal-corrugated or finned 155.1 .Vertical 155.2 ..With flue baffle 155.3 ..Having exterior heating flue 155.4 ..Having corrugated flue 155.5 ..Having undulating flue 157 ..Central magazine 158 ...Water jacket ..Circulation tube 159 ...Internal 160 ..Concentric shell 161 ...Fluid fuel 162 ...Central magazine 163 ..Exterior drum 165 ..Internal water heater 166.1 ..With internal water tube 166.2 ...Loop-type tubee 168 ...Central magazine 169 ...Coil 170 ....Header 171 ...Contracted inlet 172 ...Header 173 ...Horizontal spur 174 ...Internal fire tube 175 ...Offset water firebox 176 ...Transverse 177 ....Fluid fuel 178 ...Vertical aligned fire tube 179 ....Fluid fuel 180 ....Spur water tube 181 ...Vertical spur 167 ...Fluid fuel 182.1 ..With return fire tube 182.2 ...Having symmetrical arrangement of tubes 182.3 ...Having tubes offset from firebox ..Spiral water conduit 183 ...Fluid fuel ..Standpipe ...Water tube 184 ....Annular firebox 185 ....Loop 186 ....Spur 187 ..Transverse fire tube 164 ..Insulated outlet flue 156 ..Fluid fuel * HORIZONTAL CYLINDER 188 .Drop water baffle .Offset subjacent firebox 189 ..Water roof 190 ..Water tube .Subjacent fire tube 191 ..Beyond bridge wall 192 .Water bridge wall 193 .Water firebox 194 ..Water tube type 195 .Water tube ..Feed heater 196 ...Check-valved 197 ..Lateral-longitudinal 198 ..Lateral-vertical 199 ...Firebox 200 ..Over fuel grate 201 ..Subjacent internal fire tube 202 ..Trapped circuit ..Water grate 203 ...Downdraft 204 ...Intermediate draft 205 ...Multiple series 206 ...Solid and water bar 207 ...Updraft * PLATE .Zigzag conduit 208 ..Fluid fuel 209.1 SECTIONAL 209.2 .Feeding airr 213 .Plural firebox .Horizontal sections 214 ..Superimposed 215 ...Central connection 216 ....Fluid fuel 217 ....Water firebox 218 ...Water firebox 219 ....Central magazine ...Water tube ....Internal fire tube 220 .....Water firebox .Vertical sections 221 ..Annularly positioned 222 ...Central magazine 223 ..Longitudinally positioned 224 ...Casing 225 R ..Transversely positioned 226 ...Casing 227 ....Divided section 228 ...Divided section 229 ...Water grate 225 A ...Water heater in flue 225 B ...Water heater in boiler 225 F ...Feeding air 230 ..Two-section 212.1 .With magazine 212.2 ..With return or alternate flue 211 .Fluid or solid fuel 210 .Fluid fuel 232 .Water grate 231 .Accessories * TANK 233 .Horizontal 234 .Vertical 235.11 WATER TUBE 235.12 .Wall structure 235.13 .With fuel burners having posts and tuyeres 235.14 .Tube structure 235.15 .Headers and connections 235.16 .For plural fluids 235.17 .Having baffles 235.18 .Having seals 235.19 .D-type tube 235.21 ..Multiple D-type tubes 235.22 .Wall loop 235.23 .Having specific tube patterns 235.24 .Screens 235.25 ..Floor screens 235.26 .Having slag and ash disposal 235.27 .Locomotive-type 235.28 .Having rotary flame 235.29 .Having forced circulation system 235.31 .Having specific intenal drum and head structure 235.32 .With combustion 235.33 .With convection zone regulation 235.34 .With parallel multiple fireboxes 235.35 .With serial multiple fireboxes 238 .Offset fireboxx 239 .Superimposed firebox 240.1 .Having plural fireboxes 240.2 ..Series connected 240.3 ..Parallel connected 241 .Firebox in drum 242 .Capillary 243 ..Fluid fuel .Coil or loop 244 ..Central standpipe 245 ...Fluid fuel 246 ...Annular firebox 247 .Coil ..Horizontal 248 ...Fluid fuel 249 ..Vertical 250 R ...Fluid fuel 250 S ....Standpipe 251 ...Central magazine 252 ...Water firebox 253 .Cross 254 ..Over bridge wall ..Over firebox ...Longitudinal ....Header 255 .....Drum ...Transverse ....Header 256 .....Drum ..Transverse ...Header 257 ....Drum 258 .Downflow 259 .Drum type 260 .Flat 261 ..Volute 262 .Horizontal 263 ..Over bridge wall 264 ..Over firebox 265 .Inclined 266 .Internal fire tube 267 ..Horizontal 268 ..Inclined 269 ..Plural fire tube 270 ..Straddle 271 ..Vertical 272 ...Central magazine 273 .Longitudinal upper drum 274 ..Fluid fuel 275 .Loop 276 ..Firebox enclosing 277 ..Over bridge wall ..Over firebox 278 ...Cross 279 ...Horizontal ...Rear of bridge wall 280 ....Bridge wall header 281 ...Standpipe 282 ...Verticall 283 ....Fluid fuel .Over bridge wall 284 ..Headers at right angles 285 ..Transverse water baffle ..Water grate 286 ...Downdraft 287 ...Intermediate draft .Over firebox 288 ..Headers at right angles ..Water grate 289 ...Updraft .Rearwardly declined ..Over bridge wall 290 ...Front and rear header 291 ....Horizontal-longitudinal drum 292 .....Firebox tube 293 .....Longitudinal water baffle 294 .....Water wall 295 ....Internal water tube 296 ....Longitudinal-declined drum 297 ....Transverse drum ..Over firebox ...Front and rear header 298 ....Horizontal-longitudinal drum 299 ....Transverse drum 300 ....Tubes beyond side wall ..Plural upper transverse drum 301 ...Plural lower transverse drum 302 ...Single lower transverse drum .Rearwardly inclined ..Over firebox ...Front and rear header 303 ....Transverse drum .Separate banks 304 ..Opposite fireboxes 305 .Spur 306 ..Bridge wall header 307 ..Central standpipe 308 ...Fluid fuel 309 ...Annular firebox 310 ...Central magazine 311 ..Cross 312 ..Horizontal-longitudinal drum 313 ..Over bridge wall ..Over firebox 314 ...Central header 315 ...Declined 316 ...Horizontal 317 ..Straddle 318 ..Vertical 319 ...Fluid fuel 320 ...Central magazine 321 .Standpipe 322 ..Fluid fuel 323 ..Annular firebox 324 .Straddle ..Plural upper drum 325 ...Plural lower drumm 326 ....Cross ..Single upper drum 327 ...Plural lower drum 328 ....Fluid fuel 329 ....Cross 330 ....Plural firebox 331 .Transverse horizontal drum 332 .Vertical 333 ..Fluid fuel 334 ..Side magazine 335 ..Annular firebox 336 ..Offset firebox 337 ...Elevated ..Annular lower drum 338 ...Annular upper drum 339 ....Central magazine 340 ....Tubes over firebox 341 ...Fire tube upper drum 342 ...Spur tube upper drum 343 ...Upper drum 344 ....Central magazine 345 ..Beyond bridge wall 346 ...Gas return ...Longitudinal upper drum 347 ....Longitudinal lower drum ..Internal fire tube 348 ...Fluid fuel 349 ..Over firebox 350 ...Gas return ..Plural upper longitudinal drum 351 ...Plural lower longitudinal drum ..Plural upper transverse drum ...Plural lower transverse drum 352 ....Offset firebox 353 .Water grate 354 ..Downdraft 355 .Zigzag 356 ..Fluid fuel ..Over bridge wall 357 ...Longitudinal drum 358 ...Transverse drum 359 ..Over firebox 237 .Magazine 236 .Fluid fuel .Headers 360 ..Closures and couplings 361 ...Cleaning 362 ...Concentric tube 363 ...Drum 364 ...Tube closures 365 .Drums and couplings 366 WICK 367.1 HEAT TRANSMITTER 367.2 .Double immersed heat transmitters 367.3 .Corrugated and finned heat transmitters 367.4 .Pebble furnaces 368 WATER FIREBOX 369 .Mud ringg 370 .Plural 371 WATER GRATE .Plural firebox ..Superimposed ...Water grate 372 ....Updraft 373 .Cage 374 .Grate structure 375 ..Solid and water bar 376 .Progressive feed .Water firebox ..Solid and water bar 377 ...Updraft 378 ..Updraft 21 CHEMICAL 22 FLUID AND SOLID FUEL 23 FLUID FUEL 24 .Explosion .Plural burner 25 ..Superimposed 26 FRICTION GENERATOR * NONCOMBUSTIBLE HEATER 27 .Surface 28 .Water in contact 379 CLEANING 380 .Agitating circulator .Blow off 381 ..Bottom and surface 382 ..Bottom 383 ...Internal conduit 384 ....Ejector 385 ....Mud ring 386 ....Pan 387 ....Scraper 388 ....Valved 389 ..Surface exit 390 .Fluid jet 391 ..Horizontal fire tube boiler 392 ..Water tube boiler 393 .Mud drum 394 .Pans 395 .Sandblast 396 .Systems 397 .Trapped circuit 398 ..Feeding water 399 ..Surface and bottom exit 400 ..Surface exit 401 ...Chemical feeder 402 ...Circulating pump 403 ...Feed heater 404 ...Steam injector 405 .Wash-out nozzle 406.1 CIRCULATION 406.2 .Having anticavitation devices 406.3 .Having restrictors and orifices 406.4 .Once through 406.5 .With start-up operations 407 .Injectorr 408.1 .Having internal conduit 408.2 ..With internal geyser tube 409 ..Horizontal flue boiler 410 ...Return fire tube .Mechanical 411 ..Internal 412 FEED HEATERS 413 .Ash pan .Boiler circuit 414 ..Feed-injected .Circulatioon ..Surface exit ...Mechanical pump 415 ....Feed-injected 417 .Drip plate in boiler .Fire-engine boiler ..Auxiliary 418 ...Attached 419 ...Detachable 420 .Furnace gases 421 .Offtake flue 422 .Furnace gases and steam .Horizontal fire tube boiler 423 ..Smoke box 424 ...Exhaust pipe 425 ...Furnace gases and steam 426 ...Water tube 427 ..Smoke chamber 428 .Internal conduit 429 ..Automatic sediment valve 430 ..Blow-off delivery 431 ..Filter in boiler 432 ..Furnace gases 433 ..Trap outside boiler 434 .Locomotive tender 435 .Pan in steam space 436 ..Spray 437 .Safety valve 438 .Spray to steam space 439 .Stack 441 .Steam 442 ..Injected ...Superposed 443 ....Open to steam space 444 .Water tube boiler * REGULATION .Fuel and water 446 ..Fluid fuel 447 ...Cutoff ..Automatic control 449 ...Solid fuel 450 .Suspended boiler 448.1 AUTOMATIC CONTROL OF FLUID FUEL AND WATER 448.2 .Having fuel or feed bypass 448.3 .Multiple boiler regulation 448.4 .Once through 451 R FEEDERS 451.1 .Automaticc 451.1 ..Thermally controlled 451.2 ...Pressure-operated valve 452 .Boiler pressure .Gravity 456 ..Automatic 457 ...Heater 458 ..Heater 451 S .Once through 459 STEAM TREATMENT 460 .Boilers with superheaters .Fire tube boiler ..Horizontal 461 ...Superheater ....In fire tube 462 .....From smoke box ....Interior steam space 463 .....Internal fire tube ....Smoke box 464 .....Fire tube 465 .....Steam tube 466 ..Superheater and feed heater ..Vertical 467 ...Superheater .Flue boiler ..Vertical ...Internal water tube 468 ....Superheater .Horizontal boiler ..Superheater 469 ...Rear of firebox 470 ...Waste-heat flue .Water tube boiler ..Declined over bridge wall ...Front and rear header ....Declined drum 471 .....Superheater ....Longitudinal drum 472 .....Superheater ..Longitudinal drum 473 ...Superheater ..Over bridge wall 474 ...Superheater ..Standpipe ...Spur tube 475 ....Superheater ..Transverse drum 478 ...Superheater 477 ..Superheater and feed heater 476 ..Superheater .Superheater 480 ..Damper-controlled 481 ..Firebox 482 ..Fire tube in steam space 483 ..Indirectly heated 484 ..Separate charges 485 ..Separate furnace 486 ..Steam dome 487 ..Water-injectedd 479.1 .Automatic heat regulation of superheater 479.2 ..Having gas recirculation 479.3 ..Having flame positioning 479.4 ..With variable firing 479.5 ..Having dampers 479.6 ..Plural furnaces 479.7 ..Once through * SEPARATORS 488 .Boiler circulation 489 .Boiler return 490 .For tilting boilers 491 .Interior of boilers 492 .Steam dome 493 BRACES AND STAYS 494 CASINGS 495 CROWN SHEETS PROTECTING 496 CROWN SHEETS AND STAYS 497 FRONTS 498 .Doors 499 .Mouths 500 ..Water firebox 501 FLUID-DISPLACER 502 .Fluid fuel 503 FUEL BAFFLES 504 SAFETY DEVICES 504.1 .Fusible control 504.2 .Alarms or indicators 504.3 .Fire extinguishers 504.3 ..Fusible control 505 ..Float-controlled 506 ..Pressure-controlled 507 .Self-closing valve 508 STEAM DOMES 509 SUBMERGED STEAM CHAMBER 510 SUPPORTS 511 TUBES AND CONNECTIONS 512 TUBE SHEETS * ****************************** * DIGESTS * ****************************** DIG 1 Air heater DIG 2 Air heater - indirectly heated DIG 3 Gas flow baffles DIG 4 Once through boilers DIG 5 Critical pressure DIG 6 Damper-directed radiation DIG 7 Feeding air DIG 10 Portable units DIG 11 Removable steam-heating elements DIG 13 Tubes - composition and protection DIG 14 Tube replacement DIG 15 Valves DIG 16 Welding