WebCPC CPC COOPERATIVE PATENT CLASSIFICATION

F22D　PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER ; FEED-WATER SUPPLY ; CONTROLLING WATER LEVEL ; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN BOILERS ( chemical treatment of water, e.g. purification, C02F ; enclosed heat-exchange apparatus in general F28D ; controlling in general G05 )

F22D 1/00 Feed-water heaters, i.e. economisers or like preheaters

F22D 1/003 ・{Feed-water heater systems (F22D 1/325, F22D 1/36 and F22D 1/40 take precedence)}

F22D 1/006 ・{with heating tubes (F22D 1/24 takes precedence)}

F22D 1/02 ・with water tubes arranged in the boiler furnace, fire tubes, or flue ways (heat-exchange tubes in general F28F)

F22D 1/04 ・・the tubes having plain outer surfaces, e.g. in vertical arrangement

F22D 1/06 ・・・in horizontal arrangement

F22D 1/08 ・・the tubes having fins, ribs, gills, corrugations, or the like on their outer surfaces, e.g. in vertical arrangement

F22D 1/10 ・・・in horizontal arrangement (hollow fire-bars, grates, or the like used as water tubes F23H 3/02)

F22D 1/12 ・・Control devices, e.g. for regulating steam temperature

F22D 1/14 ・・Safety or venting devices (safety devices for boilers in general F22B 37/42)

F22D 1/16 ・with water tubes arranged otherwise than in the boiler furnace, fire tubes, or flue ways

F22D 1/18 ・・and heated indirectly

F22D 1/20 ・・and directly connected to boilers

F22D 1/22 ・・and provided for rotary movements

F22D 1/24 ・with fire tubes or flue ways traversing feed-water vessels

F22D 1/26 ・with means, other than tubes, to separate water and heating medium, e.g. bulk heaters without internal flues or tubes, jacketted smoke-boxes or flue or flues

F22D 1/28 ・for direct heat transfer, e.g. by mixing water and steam

F22D 1/30 ・・with stages, steps, baffles, dishes, circular troughs, or other means to cause interrupted or cascading fall of water (de-aeration apparatus C02F)

F22D 1/32 ・arranged to be heated by steam, e.g. bled from turbines

F22D 1/325 ・・{Schematic arrangements or control devices therefor}

F22D 1/34 ・・and returning condensate to boiler with main feed supply

F22D 1/36 ・Water and air preheating systems

F22D 1/38 ・・Constructional features of water and air preheating systems

F22D 1/40 ・Combinations of exhaust-steam and smoke-gas preheaters (for locomotives F22D 1/42)

F22D 1/42 ・specially adapted for locomotives

F22D 1/44 ・・Smoke-gas preheaters

F22D 1/46 ・・Exhaust-steam preheaters

F22D 1/48 ・・Details

F22D 1/50 ・incorporating thermal de-aeration of feed-water (de-aeration produced in the course of direct heat transfer F22D 1/28; thermal de-aeration of water per se B01D 19/00, C02F 1/20; valves for venting F16K 24/04)

F22D 3/00 Accumulators for preheated water

F22D 3/02 ・arranged within combustion chambers

F22D 3/04 ・combined with steam accumulators

F22D 3/06 ・directly connected to boilers

F22D 3/08 ・specially adapted for locomotives (locomotives boilers F22B 13/06)

F22D 3/10 ・・Control devices (controlling water feed to boilers, or water level F22D 5/00)

F22D 5/00 Controlling water feed or water level; Automatic water feeding or water-level regulators (steam traps F16T; measuring or indicating instruments G01; for indicating water level G01F; level control in general G05D 9/00)

F22D 5/02 ・with an intermediate compartment from which the water is fed by gravity after mechanically moving the compartment, the movement being controlled according to water level

F22D 5/04 ・with pivoting buckets

F22D 5/06 ・with receptacles external to, but in free communication with, the boilers and adapted to move up and down in accordance with change in water level

F22D 5/08 ・with float-actuated valves

F22D 5/10 ・・and with pistons or membranes unitary with the feed inlet valves

F22D 5/12 ・・and with dipping tubes

F22D 5/14 ・responsive to thermal expansion and contraction, e.g. of solid elements

F22D 5/16 ・・of fluids

F22D 5/18 ・for varying the speed or delivery pressure of feed pumps

F22D 5/20 ・・without floats

F22D 5/22 ・・with floats

F22D 5/24 ・with electric switches

F22D 5/26 ・Automatic feed-control systems (automatic safety devices F22B 37/42; controlling in general G05)

F22D 5/28 ・・responsive to amount of steam withdrawn; responsive to steam pressure

F22D 5/30 ・・responsive to both water level and amount of steam withdrawn or steam pressure

F22D 5/32 ・・influencing the speed or delivery pressure of the feed pumps

F22D 5/34 ・・Applications of valves (valves per se F16K)

F22D 5/36 ・・for feeding a number of steam boilers designed for different ranges of temperature and pressure

F22D 7/00 Auxiliary devices for promoting water circulation (adaptation of boilers for promoting water circulation F22B 37/34)

F22D 7/02 ・Saddles or like directing plates fitted to furnace tubes

F22D 7/04 ・Injectors for water or steam

F22D 7/06 ・Rotary devices, e.g. propellers

F22D 7/08 ・・Arrangements of pumps, e.g. outside the boilers

F22D 7/10 ・・・within the boilers

F22D 7/12 ・Control devices

F22D 7/14 ・specially adapted for locomotive boilers

F22D 11/00 Feed-water supply not provided for in other main groups

F22D 11/003 ・{Emergency feed-water supply (safety devices for boilers in general F22B 37/42)}

F22D 11/006 ・{Arrangements of feedwater cleaning with a boiler}

F22D 11/02 ・Arrangements of feed-water pumps (F22D 11/06 takes precedence; pumps per se F04)

F22D 11/04 ・・with means to eliminate steam formation

F22D 11/06 ・・for returning condensate to boiler