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Class   122LIQUID HEATERS AND VAPORIZERS
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[List of Pre Grant Publications for class 122 subclass 1R][List of Patents for class 122 subclass 1R]  1R PLANTS
 [List of Pre Grant Publications for class 122 subclass 2][List of Patents for class 122 subclass 2]2 Subclass 2 indent level is 1 Garbage
 [List of Pre Grant Publications for class 122 subclass 3][List of Patents for class 122 subclass 3]3 Subclass 3 indent level is 1 Motor vehicle
 [List of Pre Grant Publications for class 122 subclass 1A][List of Patents for class 122 subclass 1A]1A Subclass 1A indent level is 1 Air heaters
 [List of Pre Grant Publications for class 122 subclass 1B][List of Patents for class 122 subclass 1B]1B Subclass 1B indent level is 1 Once through
 [List of Pre Grant Publications for class 122 subclass 1C][List of Patents for class 122 subclass 1C]1C Subclass 1C indent level is 1 Feed water heaters
[List of Pre Grant Publications for class 122 subclass 4R][List of Patents for class 122 subclass 4R]  4R MISCELLANEOUS
 [List of Pre Grant Publications for class 122 subclass 4A][List of Patents for class 122 subclass 4A]4A Subclass 4A indent level is 1 Electric boiler
 [List of Pre Grant Publications for class 122 subclass 4C][List of Patents for class 122 subclass 4C]4C Subclass 4C indent level is 1 Water-cooled stoker
 [List of Pre Grant Publications for class 122 subclass 4D][List of Patents for class 122 subclass 4D]4D Subclass 4D indent level is 1 Catalyst
 [List of Pre Grant Publications for class 122 subclass 5][List of Patents for class 122 subclass 5]5 GAS-PRODUCER
[List of Pre Grant Publications for class 122 subclass 5.51][List of Patents for class 122 subclass 5.51]5.51 AIR-INJECTED
 [List of Pre Grant Publications for class 122 subclass 5.52][List of Patents for class 122 subclass 5.52]5.52 Subclass 5.52 indent level is 1 Combustion gas and vapor contact
[List of Pre Grant Publications for class 122 subclass 6R][List of Patents for class 122 subclass 6R]  6R INDUSTRIAL
 [List of Pre Grant Publications for class 122 subclass 6.5][List of Patents for class 122 subclass 6.5]6.5 Subclass 6.5 indent level is 1 Port
[List of Pre Grant Publications for class 122 subclass 6.6][List of Patents for class 122 subclass 6.6]6.6 Subclass 6.6 indent level is 1 Tuyeres
 [List of Pre Grant Publications for class 122 subclass 6.7][List of Patents for class 122 subclass 6.7]6.7 Subclass 6.7 indent level is 2 Forge
[List of Pre Grant Publications for class 122 subclass 7R][List of Patents for class 122 subclass 7R]  7R Subclass 7R indent level is 1 Waste heat
 [List of Pre Grant Publications for class 122 subclass 7A][List of Patents for class 122 subclass 7A]7A Subclass 7A indent level is 2 Steel converter
 [List of Pre Grant Publications for class 122 subclass 7B][List of Patents for class 122 subclass 7B]7B Subclass 7B indent level is 2 Additional burner
 [List of Pre Grant Publications for class 122 subclass 7C][List of Patents for class 122 subclass 7C]7C Subclass 7C indent level is 2 Waste sulfite
 [List of Pre Grant Publications for class 122 subclass 7D][List of Patents for class 122 subclass 7D]7D Subclass 7D indent level is 2 Carbon monoxide
[List of Pre Grant Publications for class 122 subclass 8][List of Patents for class 122 subclass 8]8 Subclass 8 indent level is 1 Water firebox
 [List of Pre Grant Publications for class 122 subclass 9][List of Patents for class 122 subclass 9]9 Subclass 9 indent level is 2 Water tube type
 [List of Pre Grant Publications for class 122 subclass 6A][List of Patents for class 122 subclass 6A]6A Subclass 6A indent level is 1 Water-cooled walls
 [List of Pre Grant Publications for class 122 subclass 6B][List of Patents for class 122 subclass 6B]6B Subclass 6B indent level is 1 Bosh plates
 [List of Pre Grant Publications for class 122 subclass 6C][List of Patents for class 122 subclass 6C]6C Subclass 6C indent level is 1 Skew arch coolers
 [List of Pre Grant Publications for class 122 subclass 10][List of Patents for class 122 subclass 10]10 FOR FLUID FUEL BURNER
 [List of Pre Grant Publications for class 122 subclass 11][List of Patents for class 122 subclass 11]11 ROTARY
 [List of Pre Grant Publications for class 122 subclass 12][List of Patents for class 122 subclass 12]12 ROTATABLY SUPPORTED
[List of Pre Grant Publications for class 122 subclass 13.01][List of Patents for class 122 subclass 13.01]13.01 STAND BOILER (E.G., WATER HEATER, ETC.)
 [List of Pre Grant Publications for class 122 subclass 13.3][List of Patents for class 122 subclass 13.3]13.3 Subclass 13.3 indent level is 1 And delivery means to dispensing feature
[List of Pre Grant Publications for class 122 subclass 14.1][List of Patents for class 122 subclass 14.1]14.1 Subclass 14.1 indent level is 1 And condition responsive feature
[List of Pre Grant Publications for class 122 subclass 14.2][List of Patents for class 122 subclass 14.2]14.2 Subclass 14.2 indent level is 2 Controls burner
[List of Pre Grant Publications for class 122 subclass 14.3][List of Patents for class 122 subclass 14.3]14.3 Subclass 14.3 indent level is 2 Having water flow control feature
 [List of Pre Grant Publications for class 122 subclass 15.1][List of Patents for class 122 subclass 15.1]15.1 Subclass 15.1 indent level is 1 Heated by liquid or steam (e.g., indirect heating, etc.)
 [List of Pre Grant Publications for class 122 subclass 16.1][List of Patents for class 122 subclass 16.1]16.1 Subclass 16.1 indent level is 1 Solid fuel burner
[List of Pre Grant Publications for class 122 subclass 17.1][List of Patents for class 122 subclass 17.1]17.1 Subclass 17.1 indent level is 1 Fluid fuel burner
 [List of Pre Grant Publications for class 122 subclass 17.2][List of Patents for class 122 subclass 17.2]17.2 Subclass 17.2 indent level is 2 Liquid fuel burner
[List of Pre Grant Publications for class 122 subclass 18.1][List of Patents for class 122 subclass 18.1]18.1 Subclass 18.1 indent level is 2 Having heat exchange feature
 [List of Pre Grant Publications for class 122 subclass 18.5][List of Patents for class 122 subclass 18.5]18.5 Subclass 18.5 indent level is 2 And external water tank
 [List of Pre Grant Publications for class 122 subclass 19.1][List of Patents for class 122 subclass 19.1]19.1 Subclass 19.1 indent level is 1 Water containing chamber or external tank having circulation feature within
 [List of Pre Grant Publications for class 122 subclass 19.2][List of Patents for class 122 subclass 19.2]19.2 Subclass 19.2 indent level is 1 And casing feature for stand boiler or external water tank therefor
[List of Pre Grant Publications for class 122 subclass 20R][List of Patents for class 122 subclass 20R]  20R SUBSIDIARY
 [List of Pre Grant Publications for class 122 subclass 20A][List of Patents for class 122 subclass 20A]20A Subclass 20A indent level is 1 Subsidiary-heater firebox
 [List of Pre Grant Publications for class 122 subclass 20B][List of Patents for class 122 subclass 20B]20B Subclass 20B indent level is 1 Subsidiary-heater offtake flue
 [List of Pre Grant Publications for class 122 subclass 29][List of Patents for class 122 subclass 29]29 ANNULAR FIREBOX
 [List of Pre Grant Publications for class 122 subclass 30][List of Patents for class 122 subclass 30]30 MAGAZINE
     INDIRECTLY HEATED
     Subclass  indent level is 1 Separate fluid
[List of Pre Grant Publications for class 122 subclass 32][List of Patents for class 122 subclass 32]32 Subclass 32 indent level is 2 Surface
[List of Pre Grant Publications for class 122 subclass 31.1][List of Patents for class 122 subclass 31.1]31.1 INDIRECTLY HEATED SEPARATE INJECTED FLUID
 [List of Pre Grant Publications for class 122 subclass 31.2][List of Patents for class 122 subclass 31.2]31.2 Subclass 31.2 indent level is 1 Submerged flame
 [List of Pre Grant Publications for class 122 subclass 35][List of Patents for class 122 subclass 35]35 ACCUMULATOR
 [List of Pre Grant Publications for class 122 subclass 36][List of Patents for class 122 subclass 36]36 AUXILIARY STEAM HEATER
[List of Pre Grant Publications for class 122 subclass 37][List of Patents for class 122 subclass 37]37 COMPARTMENT
     Subclass  indent level is 1 Auxiliary
 [List of Pre Grant Publications for class 122 subclass 38][List of Patents for class 122 subclass 38]38 Subclass 38 indent level is 2 Draft regulator
 [List of Pre Grant Publications for class 122 subclass 39][List of Patents for class 122 subclass 39]39 FILM
[List of Pre Grant Publications for class 122 subclass 40][List of Patents for class 122 subclass 40]40 FLASHER
 [List of Pre Grant Publications for class 122 subclass 41][List of Patents for class 122 subclass 41]41 Subclass 41 indent level is 1 Fluid fuel
[List of Pre Grant Publications for class 122 subclass 42][List of Patents for class 122 subclass 42]42 FIRE AND WATER TUBE
 [List of Pre Grant Publications for class 122 subclass 43][List of Patents for class 122 subclass 43]43 Subclass 43 indent level is 1 Fluid fuel
[List of Pre Grant Publications for class 122 subclass 44.1][List of Patents for class 122 subclass 44.1]44.1 FIRE TUBE
 [List of Pre Grant Publications for class 122 subclass 44.2][List of Patents for class 122 subclass 44.2]44.2 Subclass 44.2 indent level is 1 With baffle in flue
 [List of Pre Grant Publications for class 122 subclass 49][List of Patents for class 122 subclass 49]49 Subclass 49 indent level is 1 Horizontal and vertical
     Subclass  indent level is 1 Horizontal or inclined
     Subclass  indent level is 2 Water firebox
[List of Pre Grant Publications for class 122 subclass 51][List of Patents for class 122 subclass 51]51 Subclass 51 indent level is 1 Horizontal
[List of Pre Grant Publications for class 122 subclass 52][List of Patents for class 122 subclass 52]52 Subclass 52 indent level is 2 Plural
     Subclass  indent level is 2 Central firebox
 [List of Pre Grant Publications for class 122 subclass 55][List of Patents for class 122 subclass 55]55 Subclass 55 indent level is 2 Cylinder
     Subclass  indent level is 2 Depending fire tube
     Subclass  indent level is 2 Double water firebox
[List of Pre Grant Publications for class 122 subclass 58R][List of Patents for class 122 subclass 58R]  58R Subclass 58R indent level is 2 Drop water firebox
[List of Pre Grant Publications for class 122 subclass 72][List of Patents for class 122 subclass 72]72 Subclass 72 indent level is 2 Projecting into firebox
     Subclass  indent level is 2 Return and reverse
[List of Pre Grant Publications for class 122 subclass 75][List of Patents for class 122 subclass 75]75 Subclass 75 indent level is 2 Return fire tube
 [List of Pre Grant Publications for class 122 subclass 79][List of Patents for class 122 subclass 79]79 Subclass 79 indent level is 2 Subjacent water arch
 [List of Pre Grant Publications for class 122 subclass 80][List of Patents for class 122 subclass 80]80 Subclass 80 indent level is 2 Subjacent flue
 [List of Pre Grant Publications for class 122 subclass 81][List of Patents for class 122 subclass 81]81 Subclass 81 indent level is 2 Subjacent transverse fire tube
     Subclass  indent level is 2 Superjacent feed heater
 [List of Pre Grant Publications for class 122 subclass 83][List of Patents for class 122 subclass 83]83 Subclass 83 indent level is 2 Transverse diaphragm
     Subclass  indent level is 2 Two diameters
 [List of Pre Grant Publications for class 122 subclass 87][List of Patents for class 122 subclass 87]87 Subclass 87 indent level is 2 U-coupling
 [List of Pre Grant Publications for class 122 subclass 88][List of Patents for class 122 subclass 88]88 Subclass 88 indent level is 2 Upper drum
     Subclass  indent level is 2 Water arch
[List of Pre Grant Publications for class 122 subclass 90][List of Patents for class 122 subclass 90]90 Subclass 90 indent level is 2 Water firebox
 [List of Pre Grant Publications for class 122 subclass 101][List of Patents for class 122 subclass 101]101 Subclass 101 indent level is 2 Water smoke box
     Subclass  indent level is 2 Water tube
     Subclass  indent level is 3 Horizontal
 [List of Pre Grant Publications for class 122 subclass 103][List of Patents for class 122 subclass 103]103 Subclass 103 indent level is 3 Rear of fire tube
     Subclass  indent level is 3 Rearwardly declined
     Subclass  indent level is 3 Rearwardly inclined
[List of Pre Grant Publications for class 122 subclass 106][List of Patents for class 122 subclass 106]106 Subclass 106 indent level is 2 Water wall
 [List of Pre Grant Publications for class 122 subclass 109][List of Patents for class 122 subclass 109]109 Subclass 109 indent level is 1 Inclined
     Subclass  indent level is 1 Transverse
 [List of Pre Grant Publications for class 122 subclass 110][List of Patents for class 122 subclass 110]110 Subclass 110 indent level is 2 Horizontal boiler
[List of Pre Grant Publications for class 122 subclass 111][List of Patents for class 122 subclass 111]111 Subclass 111 indent level is 2 Vertical boiler
 [List of Pre Grant Publications for class 122 subclass 113][List of Patents for class 122 subclass 113]113 Subclass 113 indent level is 2 Water tube
[List of Pre Grant Publications for class 122 subclass 114][List of Patents for class 122 subclass 114]114 Subclass 114 indent level is 1 Vertical
 [List of Pre Grant Publications for class 122 subclass 116][List of Patents for class 122 subclass 116]116 Subclass 116 indent level is 2 Central fire dome
 [List of Pre Grant Publications for class 122 subclass 117][List of Patents for class 122 subclass 117]117 Subclass 117 indent level is 2 Central magazine
     Subclass  indent level is 2 Circulation tube
 [List of Pre Grant Publications for class 122 subclass 119][List of Patents for class 122 subclass 119]119 Subclass 119 indent level is 2 Cylinder
 [List of Pre Grant Publications for class 122 subclass 120][List of Patents for class 122 subclass 120]120 Subclass 120 indent level is 2 Offset firebox
[List of Pre Grant Publications for class 122 subclass 121][List of Patents for class 122 subclass 121]121 Subclass 121 indent level is 2 Return fire tube
 [List of Pre Grant Publications for class 122 subclass 123][List of Patents for class 122 subclass 123]123 Subclass 123 indent level is 2 Separate compartment
 [List of Pre Grant Publications for class 122 subclass 124][List of Patents for class 122 subclass 124]124 Subclass 124 indent level is 2 Side magazine
 [List of Pre Grant Publications for class 122 subclass 125][List of Patents for class 122 subclass 125]125 Subclass 125 indent level is 2 Top water chamber
[List of Pre Grant Publications for class 122 subclass 126][List of Patents for class 122 subclass 126]126 Subclass 126 indent level is 2 Water firebox
     Subclass  indent level is 2 Water grate
[List of Pre Grant Publications for class 122 subclass 130][List of Patents for class 122 subclass 130]130 Subclass 130 indent level is 2 Water tube
 [List of Pre Grant Publications for class 122 subclass 115][List of Patents for class 122 subclass 115]115 Subclass 115 indent level is 2 Fluid fuel
 [List of Pre Grant Publications for class 122 subclass 134][List of Patents for class 122 subclass 134]134 Subclass 134 indent level is 1 Volute
 [List of Pre Grant Publications for class 122 subclass 46][List of Patents for class 122 subclass 46]46 Subclass 46 indent level is 1 Magazine
     Subclass  indent level is 1 Flue
 [List of Pre Grant Publications for class 122 subclass 47][List of Patents for class 122 subclass 47]47 Subclass 47 indent level is 2 Horizontal
 [List of Pre Grant Publications for class 122 subclass 48][List of Patents for class 122 subclass 48]48 Subclass 48 indent level is 2 Vertical
 [List of Pre Grant Publications for class 122 subclass 45][List of Patents for class 122 subclass 45]45 Subclass 45 indent level is 1 Fluid fuel
[List of Pre Grant Publications for class 122 subclass 135.1][List of Patents for class 122 subclass 135.1]135.1 FLUE
 [List of Pre Grant Publications for class 122 subclass 135.2][List of Patents for class 122 subclass 135.2]135.2 Subclass 135.2 indent level is 1 Alternative stack
 [List of Pre Grant Publications for class 122 subclass 135.3][List of Patents for class 122 subclass 135.3]135.3 Subclass 135.3 indent level is 1 Sinusoidal flue
[List of Pre Grant Publications for class 122 subclass 136R][List of Patents for class 122 subclass 136R]  136R Subclass 136R indent level is 1 Horizontal
[List of Pre Grant Publications for class 122 subclass 137][List of Patents for class 122 subclass 137]137 Subclass 137 indent level is 2 Plural
 [List of Pre Grant Publications for class 122 subclass 139][List of Patents for class 122 subclass 139]139 Subclass 139 indent level is 2 Drop water firebox
[List of Pre Grant Publications for class 122 subclass 140.1][List of Patents for class 122 subclass 140.1]140.1 Subclass 140.1 indent level is 2 Internal water tube
[List of Pre Grant Publications for class 122 subclass 149][List of Patents for class 122 subclass 149]149 Subclass 149 indent level is 2 Return fire tube
 [List of Pre Grant Publications for class 122 subclass 150][List of Patents for class 122 subclass 150]150 Subclass 150 indent level is 3 Rear water tube
     Subclass  indent level is 3 Water smoke box
 [List of Pre Grant Publications for class 122 subclass 152][List of Patents for class 122 subclass 152]152 Subclass 152 indent level is 2 Water grate in flue
[List of Pre Grant Publications for class 122 subclass 153][List of Patents for class 122 subclass 153]153 Subclass 153 indent level is 2 Water tube
 [List of Pre Grant Publications for class 122 subclass 136C][List of Patents for class 122 subclass 136C]136C Subclass 136C indent level is 2 Horizontal-corrugated or finned
[List of Pre Grant Publications for class 122 subclass 155.1][List of Patents for class 122 subclass 155.1]155.1 Subclass 155.1 indent level is 1 Vertical
 [List of Pre Grant Publications for class 122 subclass 155.2][List of Patents for class 122 subclass 155.2]155.2 Subclass 155.2 indent level is 2 With flue baffle
 [List of Pre Grant Publications for class 122 subclass 155.3][List of Patents for class 122 subclass 155.3]155.3 Subclass 155.3 indent level is 2 Having exterior heating flue
 [List of Pre Grant Publications for class 122 subclass 155.4][List of Patents for class 122 subclass 155.4]155.4 Subclass 155.4 indent level is 2 Having corrugated flue
 [List of Pre Grant Publications for class 122 subclass 155.5][List of Patents for class 122 subclass 155.5]155.5 Subclass 155.5 indent level is 2 Having undulating flue
[List of Pre Grant Publications for class 122 subclass 157][List of Patents for class 122 subclass 157]157 Subclass 157 indent level is 2 Central magazine
     Subclass  indent level is 2 Circulation tube
[List of Pre Grant Publications for class 122 subclass 160][List of Patents for class 122 subclass 160]160 Subclass 160 indent level is 2 Concentric shell
 [List of Pre Grant Publications for class 122 subclass 163][List of Patents for class 122 subclass 163]163 Subclass 163 indent level is 2 Exterior drum
 [List of Pre Grant Publications for class 122 subclass 165][List of Patents for class 122 subclass 165]165 Subclass 165 indent level is 2 Internal water heater
[List of Pre Grant Publications for class 122 subclass 166.1][List of Patents for class 122 subclass 166.1]166.1 Subclass 166.1 indent level is 2 With internal water tube
[List of Pre Grant Publications for class 122 subclass 182.1][List of Patents for class 122 subclass 182.1]182.1 Subclass 182.1 indent level is 2 With return fire tube
     Subclass  indent level is 2 Spiral water conduit
     Subclass  indent level is 2 Standpipe
 [List of Pre Grant Publications for class 122 subclass 187][List of Patents for class 122 subclass 187]187 Subclass 187 indent level is 2 Transverse fire tube
 [List of Pre Grant Publications for class 122 subclass 164][List of Patents for class 122 subclass 164]164 Subclass 164 indent level is 2 Insulated outlet flue
 [List of Pre Grant Publications for class 122 subclass 156][List of Patents for class 122 subclass 156]156 Subclass 156 indent level is 2 Fluid fuel
     HORIZONTAL CYLINDER
 [List of Pre Grant Publications for class 122 subclass 188][List of Patents for class 122 subclass 188]188 Subclass 188 indent level is 1 Drop water baffle
     Subclass  indent level is 1 Offset subjacent firebox
 [List of Pre Grant Publications for class 122 subclass 189][List of Patents for class 122 subclass 189]189 Subclass 189 indent level is 2 Water roof
 [List of Pre Grant Publications for class 122 subclass 190][List of Patents for class 122 subclass 190]190 Subclass 190 indent level is 2 Water tube
     Subclass  indent level is 1 Subjacent fire tube
 [List of Pre Grant Publications for class 122 subclass 191][List of Patents for class 122 subclass 191]191 Subclass 191 indent level is 2 Beyond bridge wall
 [List of Pre Grant Publications for class 122 subclass 192][List of Patents for class 122 subclass 192]192 Subclass 192 indent level is 1 Water bridge wall
[List of Pre Grant Publications for class 122 subclass 193][List of Patents for class 122 subclass 193]193 Subclass 193 indent level is 1 Water firebox
 [List of Pre Grant Publications for class 122 subclass 194][List of Patents for class 122 subclass 194]194 Subclass 194 indent level is 2 Water tube type
[List of Pre Grant Publications for class 122 subclass 195][List of Patents for class 122 subclass 195]195 Subclass 195 indent level is 1 Water tube
     Subclass  indent level is 2 Feed heater
 [List of Pre Grant Publications for class 122 subclass 197][List of Patents for class 122 subclass 197]197 Subclass 197 indent level is 2 Lateral-longitudinal
[List of Pre Grant Publications for class 122 subclass 198][List of Patents for class 122 subclass 198]198 Subclass 198 indent level is 2 Lateral-vertical
 [List of Pre Grant Publications for class 122 subclass 200][List of Patents for class 122 subclass 200]200 Subclass 200 indent level is 2 Over fuel grate
 [List of Pre Grant Publications for class 122 subclass 201][List of Patents for class 122 subclass 201]201 Subclass 201 indent level is 2 Subjacent internal fire tube
 [List of Pre Grant Publications for class 122 subclass 202][List of Patents for class 122 subclass 202]202 Subclass 202 indent level is 2 Trapped circuit
     Subclass  indent level is 2 Water grate
     PLATE
     Subclass  indent level is 1 Zigzag conduit
 [List of Pre Grant Publications for class 122 subclass 208][List of Patents for class 122 subclass 208]208 Subclass 208 indent level is 2 Fluid fuel
[List of Pre Grant Publications for class 122 subclass 209.1][List of Patents for class 122 subclass 209.1]209.1 SECTIONAL
 [List of Pre Grant Publications for class 122 subclass 209.2][List of Patents for class 122 subclass 209.2]209.2 Subclass 209.2 indent level is 1 Feeding air
 [List of Pre Grant Publications for class 122 subclass 213][List of Patents for class 122 subclass 213]213 Subclass 213 indent level is 1 Plural firebox
     Subclass  indent level is 1 Horizontal sections
[List of Pre Grant Publications for class 122 subclass 214][List of Patents for class 122 subclass 214]214 Subclass 214 indent level is 2 Superimposed
     Subclass  indent level is 1 Vertical sections
[List of Pre Grant Publications for class 122 subclass 221][List of Patents for class 122 subclass 221]221 Subclass 221 indent level is 2 Annularly positioned
[List of Pre Grant Publications for class 122 subclass 223][List of Patents for class 122 subclass 223]223 Subclass 223 indent level is 2 Longitudinally positioned
[List of Pre Grant Publications for class 122 subclass 225R][List of Patents for class 122 subclass 225R]  225R Subclass 225R indent level is 2 Transversely positioned
 [List of Pre Grant Publications for class 122 subclass 230][List of Patents for class 122 subclass 230]230 Subclass 230 indent level is 2 Two-section
[List of Pre Grant Publications for class 122 subclass 212.1][List of Patents for class 122 subclass 212.1]212.1 Subclass 212.1 indent level is 1 With magazine
 [List of Pre Grant Publications for class 122 subclass 212.2][List of Patents for class 122 subclass 212.2]212.2 Subclass 212.2 indent level is 2 With return or alternate flue
 [List of Pre Grant Publications for class 122 subclass 211][List of Patents for class 122 subclass 211]211 Subclass 211 indent level is 1 Fluid or solid fuel
 [List of Pre Grant Publications for class 122 subclass 210][List of Patents for class 122 subclass 210]210 Subclass 210 indent level is 1 Fluid fuel
 [List of Pre Grant Publications for class 122 subclass 232][List of Patents for class 122 subclass 232]232 Subclass 232 indent level is 1 Water grate
 [List of Pre Grant Publications for class 122 subclass 231][List of Patents for class 122 subclass 231]231 Subclass 231 indent level is 1 Accessories
     TANK
 [List of Pre Grant Publications for class 122 subclass 233][List of Patents for class 122 subclass 233]233 Subclass 233 indent level is 1 Horizontal
 [List of Pre Grant Publications for class 122 subclass 234][List of Patents for class 122 subclass 234]234 Subclass 234 indent level is 1 Vertical
[List of Pre Grant Publications for class 122 subclass 235.11][List of Patents for class 122 subclass 235.11]235.11 WATER TUBE
 [List of Pre Grant Publications for class 122 subclass 235.12][List of Patents for class 122 subclass 235.12]235.12 Subclass 235.12 indent level is 1 Wall structure
 [List of Pre Grant Publications for class 122 subclass 235.13][List of Patents for class 122 subclass 235.13]235.13 Subclass 235.13 indent level is 1 With fuel burners having posts and tuyeres
 [List of Pre Grant Publications for class 122 subclass 235.14][List of Patents for class 122 subclass 235.14]235.14 Subclass 235.14 indent level is 1 Tube structure
 [List of Pre Grant Publications for class 122 subclass 235.15][List of Patents for class 122 subclass 235.15]235.15 Subclass 235.15 indent level is 1 Headers and connections
 [List of Pre Grant Publications for class 122 subclass 235.16][List of Patents for class 122 subclass 235.16]235.16 Subclass 235.16 indent level is 1 For plural fluids
 [List of Pre Grant Publications for class 122 subclass 235.17][List of Patents for class 122 subclass 235.17]235.17 Subclass 235.17 indent level is 1 Having baffles
 [List of Pre Grant Publications for class 122 subclass 235.18][List of Patents for class 122 subclass 235.18]235.18 Subclass 235.18 indent level is 1 Having seals
[List of Pre Grant Publications for class 122 subclass 235.19][List of Patents for class 122 subclass 235.19]235.19 Subclass 235.19 indent level is 1 D-type tube
 [List of Pre Grant Publications for class 122 subclass 235.21][List of Patents for class 122 subclass 235.21]235.21 Subclass 235.21 indent level is 2 Multiple D-type tubes
 [List of Pre Grant Publications for class 122 subclass 235.22][List of Patents for class 122 subclass 235.22]235.22 Subclass 235.22 indent level is 1 Wall loop
 [List of Pre Grant Publications for class 122 subclass 235.23][List of Patents for class 122 subclass 235.23]235.23 Subclass 235.23 indent level is 1 Having specific tube patterns
[List of Pre Grant Publications for class 122 subclass 235.24][List of Patents for class 122 subclass 235.24]235.24 Subclass 235.24 indent level is 1 Screens
 [List of Pre Grant Publications for class 122 subclass 235.25][List of Patents for class 122 subclass 235.25]235.25 Subclass 235.25 indent level is 2 Floor screens
 [List of Pre Grant Publications for class 122 subclass 235.26][List of Patents for class 122 subclass 235.26]235.26 Subclass 235.26 indent level is 1 Having slag and ash disposal
 [List of Pre Grant Publications for class 122 subclass 235.27][List of Patents for class 122 subclass 235.27]235.27 Subclass 235.27 indent level is 1 Locomotive-type
 [List of Pre Grant Publications for class 122 subclass 235.28][List of Patents for class 122 subclass 235.28]235.28 Subclass 235.28 indent level is 1 Having rotary flame
 [List of Pre Grant Publications for class 122 subclass 235.29][List of Patents for class 122 subclass 235.29]235.29 Subclass 235.29 indent level is 1 Having forced circulation system
 [List of Pre Grant Publications for class 122 subclass 235.31][List of Patents for class 122 subclass 235.31]235.31 Subclass 235.31 indent level is 1 Having specific intenal drum and head structure
 [List of Pre Grant Publications for class 122 subclass 235.32][List of Patents for class 122 subclass 235.32]235.32 Subclass 235.32 indent level is 1 With combustion
 [List of Pre Grant Publications for class 122 subclass 235.33][List of Patents for class 122 subclass 235.33]235.33 Subclass 235.33 indent level is 1 With convection zone regulation
 [List of Pre Grant Publications for class 122 subclass 235.34][List of Patents for class 122 subclass 235.34]235.34 Subclass 235.34 indent level is 1 With parallel multiple fireboxes
 [List of Pre Grant Publications for class 122 subclass 235.35][List of Patents for class 122 subclass 235.35]235.35 Subclass 235.35 indent level is 1 With serial multiple fireboxes
 [List of Pre Grant Publications for class 122 subclass 238][List of Patents for class 122 subclass 238]238 Subclass 238 indent level is 1 Offset firebox
 [List of Pre Grant Publications for class 122 subclass 239][List of Patents for class 122 subclass 239]239 Subclass 239 indent level is 1 Superimposed firebox
[List of Pre Grant Publications for class 122 subclass 240.1][List of Patents for class 122 subclass 240.1]240.1 Subclass 240.1 indent level is 1 Having plural fireboxes
 [List of Pre Grant Publications for class 122 subclass 240.2][List of Patents for class 122 subclass 240.2]240.2 Subclass 240.2 indent level is 2 Series connected
 [List of Pre Grant Publications for class 122 subclass 240.3][List of Patents for class 122 subclass 240.3]240.3 Subclass 240.3 indent level is 2 Parallel connected
 [List of Pre Grant Publications for class 122 subclass 241][List of Patents for class 122 subclass 241]241 Subclass 241 indent level is 1 Firebox in drum
[List of Pre Grant Publications for class 122 subclass 242][List of Patents for class 122 subclass 242]242 Subclass 242 indent level is 1 Capillary
 [List of Pre Grant Publications for class 122 subclass 243][List of Patents for class 122 subclass 243]243 Subclass 243 indent level is 2 Fluid fuel
     Subclass  indent level is 1 Coil or loop
[List of Pre Grant Publications for class 122 subclass 244][List of Patents for class 122 subclass 244]244 Subclass 244 indent level is 2 Central standpipe
[List of Pre Grant Publications for class 122 subclass 247][List of Patents for class 122 subclass 247]247 Subclass 247 indent level is 1 Coil
     Subclass  indent level is 2 Horizontal
[List of Pre Grant Publications for class 122 subclass 249][List of Patents for class 122 subclass 249]249 Subclass 249 indent level is 2 Vertical
[List of Pre Grant Publications for class 122 subclass 253][List of Patents for class 122 subclass 253]253 Subclass 253 indent level is 1 Cross
 [List of Pre Grant Publications for class 122 subclass 254][List of Patents for class 122 subclass 254]254 Subclass 254 indent level is 2 Over bridge wall
     Subclass  indent level is 2 Over firebox
     Subclass  indent level is 3 Longitudinal
     Subclass  indent level is 4 Header
     Subclass  indent level is 3 Transverse
     Subclass  indent level is 4 Header
     Subclass  indent level is 2 Transverse
     Subclass  indent level is 3 Header
 [List of Pre Grant Publications for class 122 subclass 258][List of Patents for class 122 subclass 258]258 Subclass 258 indent level is 1 Downflow
 [List of Pre Grant Publications for class 122 subclass 259][List of Patents for class 122 subclass 259]259 Subclass 259 indent level is 1 Drum type
[List of Pre Grant Publications for class 122 subclass 260][List of Patents for class 122 subclass 260]260 Subclass 260 indent level is 1 Flat
 [List of Pre Grant Publications for class 122 subclass 261][List of Patents for class 122 subclass 261]261 Subclass 261 indent level is 2 Volute
[List of Pre Grant Publications for class 122 subclass 262][List of Patents for class 122 subclass 262]262 Subclass 262 indent level is 1 Horizontal
 [List of Pre Grant Publications for class 122 subclass 263][List of Patents for class 122 subclass 263]263 Subclass 263 indent level is 2 Over bridge wall
 [List of Pre Grant Publications for class 122 subclass 264][List of Patents for class 122 subclass 264]264 Subclass 264 indent level is 2 Over firebox
 [List of Pre Grant Publications for class 122 subclass 265][List of Patents for class 122 subclass 265]265 Subclass 265 indent level is 1 Inclined
[List of Pre Grant Publications for class 122 subclass 266][List of Patents for class 122 subclass 266]266 Subclass 266 indent level is 1 Internal fire tube
 [List of Pre Grant Publications for class 122 subclass 267][List of Patents for class 122 subclass 267]267 Subclass 267 indent level is 2 Horizontal
 [List of Pre Grant Publications for class 122 subclass 268][List of Patents for class 122 subclass 268]268 Subclass 268 indent level is 2 Inclined
 [List of Pre Grant Publications for class 122 subclass 269][List of Patents for class 122 subclass 269]269 Subclass 269 indent level is 2 Plural fire tube
 [List of Pre Grant Publications for class 122 subclass 270][List of Patents for class 122 subclass 270]270 Subclass 270 indent level is 2 Straddle
[List of Pre Grant Publications for class 122 subclass 271][List of Patents for class 122 subclass 271]271 Subclass 271 indent level is 2 Vertical
[List of Pre Grant Publications for class 122 subclass 273][List of Patents for class 122 subclass 273]273 Subclass 273 indent level is 1 Longitudinal upper drum
 [List of Pre Grant Publications for class 122 subclass 274][List of Patents for class 122 subclass 274]274 Subclass 274 indent level is 2 Fluid fuel
[List of Pre Grant Publications for class 122 subclass 275][List of Patents for class 122 subclass 275]275 Subclass 275 indent level is 1 Loop
 [List of Pre Grant Publications for class 122 subclass 276][List of Patents for class 122 subclass 276]276 Subclass 276 indent level is 2 Firebox enclosing
 [List of Pre Grant Publications for class 122 subclass 277][List of Patents for class 122 subclass 277]277 Subclass 277 indent level is 2 Over bridge wall
     Subclass  indent level is 2 Over firebox
     Subclass  indent level is 1 Over bridge wall
 [List of Pre Grant Publications for class 122 subclass 284][List of Patents for class 122 subclass 284]284 Subclass 284 indent level is 2 Headers at right angles
 [List of Pre Grant Publications for class 122 subclass 285][List of Patents for class 122 subclass 285]285 Subclass 285 indent level is 2 Transverse water baffle
     Subclass  indent level is 2 Water grate
     Subclass  indent level is 1 Over firebox
 [List of Pre Grant Publications for class 122 subclass 288][List of Patents for class 122 subclass 288]288 Subclass 288 indent level is 2 Headers at right angles
     Subclass  indent level is 2 Water grate
     Subclass  indent level is 1 Rearwardly declined
     Subclass  indent level is 2 Over bridge wall
     Subclass  indent level is 2 Over firebox
     Subclass  indent level is 2 Plural upper transverse drum
     Subclass  indent level is 1 Rearwardly inclined
     Subclass  indent level is 2 Over firebox
     Subclass  indent level is 3 Front and rear header
     Subclass  indent level is 1 Separate banks
 [List of Pre Grant Publications for class 122 subclass 304][List of Patents for class 122 subclass 304]304 Subclass 304 indent level is 2 Opposite fireboxes
[List of Pre Grant Publications for class 122 subclass 305][List of Patents for class 122 subclass 305]305 Subclass 305 indent level is 1 Spur
 [List of Pre Grant Publications for class 122 subclass 306][List of Patents for class 122 subclass 306]306 Subclass 306 indent level is 2 Bridge wall header
[List of Pre Grant Publications for class 122 subclass 307][List of Patents for class 122 subclass 307]307 Subclass 307 indent level is 2 Central standpipe
 [List of Pre Grant Publications for class 122 subclass 311][List of Patents for class 122 subclass 311]311 Subclass 311 indent level is 2 Cross
 [List of Pre Grant Publications for class 122 subclass 312][List of Patents for class 122 subclass 312]312 Subclass 312 indent level is 2 Horizontal-longitudinal drum
 [List of Pre Grant Publications for class 122 subclass 313][List of Patents for class 122 subclass 313]313 Subclass 313 indent level is 2 Over bridge wall
     Subclass  indent level is 2 Over firebox
 [List of Pre Grant Publications for class 122 subclass 317][List of Patents for class 122 subclass 317]317 Subclass 317 indent level is 2 Straddle
[List of Pre Grant Publications for class 122 subclass 318][List of Patents for class 122 subclass 318]318 Subclass 318 indent level is 2 Vertical
[List of Pre Grant Publications for class 122 subclass 321][List of Patents for class 122 subclass 321]321 Subclass 321 indent level is 1 Standpipe
 [List of Pre Grant Publications for class 122 subclass 322][List of Patents for class 122 subclass 322]322 Subclass 322 indent level is 2 Fluid fuel
 [List of Pre Grant Publications for class 122 subclass 323][List of Patents for class 122 subclass 323]323 Subclass 323 indent level is 2 Annular firebox
[List of Pre Grant Publications for class 122 subclass 324][List of Patents for class 122 subclass 324]324 Subclass 324 indent level is 1 Straddle
     Subclass  indent level is 2 Plural upper drum
     Subclass  indent level is 2 Single upper drum
 [List of Pre Grant Publications for class 122 subclass 331][List of Patents for class 122 subclass 331]331 Subclass 331 indent level is 1 Transverse horizontal drum
[List of Pre Grant Publications for class 122 subclass 332][List of Patents for class 122 subclass 332]332 Subclass 332 indent level is 1 Vertical
 [List of Pre Grant Publications for class 122 subclass 333][List of Patents for class 122 subclass 333]333 Subclass 333 indent level is 2 Fluid fuel
 [List of Pre Grant Publications for class 122 subclass 334][List of Patents for class 122 subclass 334]334 Subclass 334 indent level is 2 Side magazine
 [List of Pre Grant Publications for class 122 subclass 335][List of Patents for class 122 subclass 335]335 Subclass 335 indent level is 2 Annular firebox
[List of Pre Grant Publications for class 122 subclass 336][List of Patents for class 122 subclass 336]336 Subclass 336 indent level is 2 Offset firebox
     Subclass  indent level is 2 Annular lower drum
[List of Pre Grant Publications for class 122 subclass 345][List of Patents for class 122 subclass 345]345 Subclass 345 indent level is 2 Beyond bridge wall
 [List of Pre Grant Publications for class 122 subclass 346][List of Patents for class 122 subclass 346]346 Subclass 346 indent level is 3 Gas return
     Subclass  indent level is 3 Longitudinal upper drum
     Subclass  indent level is 2 Internal fire tube
[List of Pre Grant Publications for class 122 subclass 349][List of Patents for class 122 subclass 349]349 Subclass 349 indent level is 2 Over firebox
     Subclass  indent level is 2 Plural upper longitudinal drum
     Subclass  indent level is 2 Plural upper transverse drum
     Subclass  indent level is 3 Plural lower transverse drum
[List of Pre Grant Publications for class 122 subclass 353][List of Patents for class 122 subclass 353]353 Subclass 353 indent level is 1 Water grate
 [List of Pre Grant Publications for class 122 subclass 354][List of Patents for class 122 subclass 354]354 Subclass 354 indent level is 2 Downdraft
[List of Pre Grant Publications for class 122 subclass 355][List of Patents for class 122 subclass 355]355 Subclass 355 indent level is 1 Zigzag
 [List of Pre Grant Publications for class 122 subclass 356][List of Patents for class 122 subclass 356]356 Subclass 356 indent level is 2 Fluid fuel
     Subclass  indent level is 2 Over bridge wall
 [List of Pre Grant Publications for class 122 subclass 359][List of Patents for class 122 subclass 359]359 Subclass 359 indent level is 2 Over firebox
 [List of Pre Grant Publications for class 122 subclass 237][List of Patents for class 122 subclass 237]237 Subclass 237 indent level is 1 Magazine
 [List of Pre Grant Publications for class 122 subclass 236][List of Patents for class 122 subclass 236]236 Subclass 236 indent level is 1 Fluid fuel
     Subclass  indent level is 1 Headers
[List of Pre Grant Publications for class 122 subclass 360][List of Patents for class 122 subclass 360]360 Subclass 360 indent level is 2 Closures and couplings
 [List of Pre Grant Publications for class 122 subclass 365][List of Patents for class 122 subclass 365]365 Subclass 365 indent level is 1 Drums and couplings
 [List of Pre Grant Publications for class 122 subclass 366][List of Patents for class 122 subclass 366]366 WICK
[List of Pre Grant Publications for class 122 subclass 367.1][List of Patents for class 122 subclass 367.1]367.1 HEAT TRANSMITTER
 [List of Pre Grant Publications for class 122 subclass 367.2][List of Patents for class 122 subclass 367.2]367.2 Subclass 367.2 indent level is 1 Double immersed heat transmitters
 [List of Pre Grant Publications for class 122 subclass 367.3][List of Patents for class 122 subclass 367.3]367.3 Subclass 367.3 indent level is 1 Corrugated and finned heat transmitters
 [List of Pre Grant Publications for class 122 subclass 367.4][List of Patents for class 122 subclass 367.4]367.4 Subclass 367.4 indent level is 1 Pebble furnaces
[List of Pre Grant Publications for class 122 subclass 368][List of Patents for class 122 subclass 368]368 WATER FIREBOX
 [List of Pre Grant Publications for class 122 subclass 369][List of Patents for class 122 subclass 369]369 Subclass 369 indent level is 1 Mud ring
 [List of Pre Grant Publications for class 122 subclass 370][List of Patents for class 122 subclass 370]370 Subclass 370 indent level is 1 Plural
[List of Pre Grant Publications for class 122 subclass 371][List of Patents for class 122 subclass 371]371 WATER GRATE
     Subclass  indent level is 1 Plural firebox
     Subclass  indent level is 2 Superimposed
     Subclass  indent level is 3 Water grate
 [List of Pre Grant Publications for class 122 subclass 373][List of Patents for class 122 subclass 373]373 Subclass 373 indent level is 1 Cage
[List of Pre Grant Publications for class 122 subclass 374][List of Patents for class 122 subclass 374]374 Subclass 374 indent level is 1 Grate structure
 [List of Pre Grant Publications for class 122 subclass 375][List of Patents for class 122 subclass 375]375 Subclass 375 indent level is 2 Solid and water bar
 [List of Pre Grant Publications for class 122 subclass 376][List of Patents for class 122 subclass 376]376 Subclass 376 indent level is 1 Progressive feed
     Subclass  indent level is 1 Water firebox
     Subclass  indent level is 2 Solid and water bar
 [List of Pre Grant Publications for class 122 subclass 378][List of Patents for class 122 subclass 378]378 Subclass 378 indent level is 2 Updraft
 [List of Pre Grant Publications for class 122 subclass 21][List of Patents for class 122 subclass 21]21 CHEMICAL
 [List of Pre Grant Publications for class 122 subclass 22][List of Patents for class 122 subclass 22]22 FLUID AND SOLID FUEL
[List of Pre Grant Publications for class 122 subclass 23][List of Patents for class 122 subclass 23]23 FLUID FUEL
 [List of Pre Grant Publications for class 122 subclass 24][List of Patents for class 122 subclass 24]24 Subclass 24 indent level is 1 Explosion
     Subclass  indent level is 1 Plural burner
 [List of Pre Grant Publications for class 122 subclass 25][List of Patents for class 122 subclass 25]25 Subclass 25 indent level is 2 Superimposed
 [List of Pre Grant Publications for class 122 subclass 26][List of Patents for class 122 subclass 26]26 FRICTION GENERATOR
     NONCOMBUSTIBLE HEATER
 [List of Pre Grant Publications for class 122 subclass 27][List of Patents for class 122 subclass 27]27 Subclass 27 indent level is 1 Surface
 [List of Pre Grant Publications for class 122 subclass 28][List of Patents for class 122 subclass 28]28 Subclass 28 indent level is 1 Water in contact
[List of Pre Grant Publications for class 122 subclass 379][List of Patents for class 122 subclass 379]379 CLEANING
 [List of Pre Grant Publications for class 122 subclass 380][List of Patents for class 122 subclass 380]380 Subclass 380 indent level is 1 Agitating circulator
     Subclass  indent level is 1 Blow off
 [List of Pre Grant Publications for class 122 subclass 381][List of Patents for class 122 subclass 381]381 Subclass 381 indent level is 2 Bottom and surface
[List of Pre Grant Publications for class 122 subclass 382][List of Patents for class 122 subclass 382]382 Subclass 382 indent level is 2 Bottom
 [List of Pre Grant Publications for class 122 subclass 389][List of Patents for class 122 subclass 389]389 Subclass 389 indent level is 2 Surface exit
[List of Pre Grant Publications for class 122 subclass 390][List of Patents for class 122 subclass 390]390 Subclass 390 indent level is 1 Fluid jet
 [List of Pre Grant Publications for class 122 subclass 391][List of Patents for class 122 subclass 391]391 Subclass 391 indent level is 2 Horizontal fire tube boiler
 [List of Pre Grant Publications for class 122 subclass 392][List of Patents for class 122 subclass 392]392 Subclass 392 indent level is 2 Water tube boiler
 [List of Pre Grant Publications for class 122 subclass 393][List of Patents for class 122 subclass 393]393 Subclass 393 indent level is 1 Mud drum
 [List of Pre Grant Publications for class 122 subclass 394][List of Patents for class 122 subclass 394]394 Subclass 394 indent level is 1 Pans
 [List of Pre Grant Publications for class 122 subclass 395][List of Patents for class 122 subclass 395]395 Subclass 395 indent level is 1 Sandblast
 [List of Pre Grant Publications for class 122 subclass 396][List of Patents for class 122 subclass 396]396 Subclass 396 indent level is 1 Systems
[List of Pre Grant Publications for class 122 subclass 397][List of Patents for class 122 subclass 397]397 Subclass 397 indent level is 1 Trapped circuit
 [List of Pre Grant Publications for class 122 subclass 398][List of Patents for class 122 subclass 398]398 Subclass 398 indent level is 2 Feeding water
 [List of Pre Grant Publications for class 122 subclass 399][List of Patents for class 122 subclass 399]399 Subclass 399 indent level is 2 Surface and bottom exit
[List of Pre Grant Publications for class 122 subclass 400][List of Patents for class 122 subclass 400]400 Subclass 400 indent level is 2 Surface exit
 [List of Pre Grant Publications for class 122 subclass 405][List of Patents for class 122 subclass 405]405 Subclass 405 indent level is 1 Wash-out nozzle
[List of Pre Grant Publications for class 122 subclass 406.1][List of Patents for class 122 subclass 406.1]406.1 CIRCULATION
 [List of Pre Grant Publications for class 122 subclass 406.2][List of Patents for class 122 subclass 406.2]406.2 Subclass 406.2 indent level is 1 Having anticavitation devices
 [List of Pre Grant Publications for class 122 subclass 406.3][List of Patents for class 122 subclass 406.3]406.3 Subclass 406.3 indent level is 1 Having restrictors and orifices
 [List of Pre Grant Publications for class 122 subclass 406.4][List of Patents for class 122 subclass 406.4]406.4 Subclass 406.4 indent level is 1 Once through
 [List of Pre Grant Publications for class 122 subclass 406.5][List of Patents for class 122 subclass 406.5]406.5 Subclass 406.5 indent level is 1 With start-up operations
 [List of Pre Grant Publications for class 122 subclass 407][List of Patents for class 122 subclass 407]407 Subclass 407 indent level is 1 Injector
[List of Pre Grant Publications for class 122 subclass 408.1][List of Patents for class 122 subclass 408.1]408.1 Subclass 408.1 indent level is 1 Having internal conduit
 [List of Pre Grant Publications for class 122 subclass 408.2][List of Patents for class 122 subclass 408.2]408.2 Subclass 408.2 indent level is 2 With internal geyser tube
[List of Pre Grant Publications for class 122 subclass 409][List of Patents for class 122 subclass 409]409 Subclass 409 indent level is 2 Horizontal flue boiler
     Subclass  indent level is 1 Mechanical
 [List of Pre Grant Publications for class 122 subclass 411][List of Patents for class 122 subclass 411]411 Subclass 411 indent level is 2 Internal
[List of Pre Grant Publications for class 122 subclass 412][List of Patents for class 122 subclass 412]412 FEED HEATERS
 [List of Pre Grant Publications for class 122 subclass 413][List of Patents for class 122 subclass 413]413 Subclass 413 indent level is 1 Ash pan
     Subclass  indent level is 1 Boiler ci