1. CPC Sections
  2. CPC Section F
  3. CPC Class F22
  4. CPC Subclass F22D
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CPC
COOPERATIVE PATENT CLASSIFICATION
F22D
PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS [2025-01]
F22D 1/00
Feed-water heaters, i.e. economisers or like preheaters [2013-01]
F22D 1/003
.
{Feed-water heater systems (F22D 1/325, F22D 1/36 and F22D 1/40 take precedence)} [2013-01]
F22D 1/006
.
{with heating tubes (F22D 1/24 takes precedence)} [2013-01]
F22D 1/02
.
with water tubes arranged in the boiler furnace, fire tubes or flue ways [2025-01]
F22D 1/04
. .
the tubes having plain outer surfaces, e.g. in vertical arrangement [2013-01]
F22D 1/06
. . .
in horizontal arrangement [2013-01]
F22D 1/08
. .
the tubes having fins, ribs, gills, corrugations, or the like on their outer surfaces, e.g. in vertical arrangement [2013-01]
F22D 1/10
. . .
in horizontal arrangement [2025-01]
F22D 1/12
. .
Control devices, e.g. for regulating steam temperature [2013-01]
F22D 1/14
. .
Safety or venting devices [2025-01]
F22D 1/16
.
with water tubes arranged otherwise than in the boiler furnace, fire tubes, or flue ways [2013-01]
F22D 1/18
. .
and heated indirectly [2013-01]
F22D 1/20
. .
and directly connected to boilers [2013-01]
F22D 1/22
. .
and provided for rotary movements [2013-01]
F22D 1/24
.
with fire tubes or flue ways traversing feed-water vessels [2013-01]
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 [2013-01]
F22D 1/28
.
for direct heat transfer, e.g. by mixing water and steam [2013-01]
F22D 1/30
. .
with stages, steps, baffles, dishes, circular troughs, or other means to cause interrupted or cascading fall of water [2025-01]
F22D 1/32
.
arranged to be heated by steam, e.g. bled from turbines [2013-01]
F22D 1/325
. .
{Schematic arrangements or control devices therefor} [2013-01]
F22D 1/34
. .
and returning condensate to boiler with main feed supply [2013-01]
F22D 1/36
.
Water and air preheating systems [2013-01]
F22D 1/38
. .
Constructional features of water and air preheating systems [2013-01]
F22D 1/40
.
Combinations of exhaust-steam and smoke-gas preheaters [2025-01]
F22D 1/42
.
specially adapted for locomotives [2013-01]
F22D 1/44
. .
Smoke-gas preheaters [2013-01]
F22D 1/46
. .
Exhaust-steam preheaters [2013-01]
F22D 1/48
. .
Details [2013-01]
F22D 1/50
.
incorporating thermal de-aeration of feed-water (de-aeration produced in the course of direct heat transfer F22D 1/28) [2025-01]
F22D 3/00
Accumulators for preheated water [2013-01]
F22D 3/02
.
arranged within combustion chambers [2013-01]
F22D 3/04
.
combined with steam accumulators [2013-01]
F22D 3/06
.
directly connected to boilers [2013-01]
F22D 3/08
.
specially adapted for locomotives [2025-01]
F22D 3/10
. .
Control devices [2025-01]
F22D 5/00
Controlling water feed or water level; Automatic water feeding or water-level regulators [2025-01]
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 [2013-01]
F22D 5/04
.
with pivoting buckets [2013-01]
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 [2013-01]
F22D 5/08
.
with float-actuated valves [2013-01]
F22D 5/10
. .
and with pistons or membranes unitary with the feed inlet valves [2013-01]
F22D 5/12
. .
and with dipping tubes [2013-01]
F22D 5/14
.
responsive to thermal expansion and contraction, e.g. of solid elements [2013-01]
F22D 5/16
. .
of fluids [2013-01]
F22D 5/18
.
for varying the speed or delivery pressure of feed pumps [2013-01]
F22D 5/20
. .
without floats [2013-01]
F22D 5/22
. .
with floats [2013-01]
F22D 5/24
.
with electric switches [2013-01]
F22D 5/26
.
Automatic feed-control systems [2025-01]
F22D 5/28
. .
responsive to amount of steam withdrawn; responsive to steam pressure [2013-01]
F22D 5/30
. .
responsive to both water level and amount of steam withdrawn or steam pressure [2013-01]
F22D 5/32
. .
influencing the speed or delivery pressure of the feed pumps [2013-01]
F22D 5/34
. .
Applications of valves [2025-01]
F22D 5/36
. .
for feeding a number of steam boilers designed for different ranges of temperature and pressure [2013-01]
F22D 7/00
Auxiliary devices for promoting water circulation [2025-01]
F22D 7/02
.
Saddles or like directing plates fitted to furnace tubes [2013-01]
F22D 7/04
.
Injectors for water or steam [2013-01]
F22D 7/06
.
Rotary devices, e.g. propellers [2013-01]
F22D 7/08
. .
Arrangements of pumps, e.g. outside the boilers [2013-01]
F22D 7/10
. . .
within the boilers [2013-01]
F22D 7/12
.
Control devices [2013-01]
F22D 7/14
.
specially adapted for locomotive boilers [2013-01]
F22D 11/00
Feed-water supply not provided for in other main groups [2013-01]
F22D 11/003
.
{Emergency feed-water supply} [2025-01]
F22D 11/006
.
{Arrangements of feedwater cleaning with a boiler} [2013-01]
F22D 11/02
.
Arrangements of feed-water pumps [2025-01]
F22D 11/04
. .
with means to eliminate steam formation [2013-01]
F22D 11/06
. .
for returning condensate to boiler [2013-01]