|  | F |
SECTION F — MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING

LIGHTING; HEATING

|  | F27 |
FURNACES; KILNS; OVENS; RETORTS (specially adapted for a purpose covered by a single other class and specifically mentioned in that class, see the class in question, e.g. bakery ovens Fulltext... Hierarchy... Expanded...A21B, glass melting furnaces Fulltext... Hierarchy... Expanded...C03B, coke or gas-making apparatus Fulltext... Hierarchy... Expanded...C10B, Fulltext... Hierarchy... Expanded...C10J, apparatus for cracking hydrocarbons Fulltext... Hierarchy... Expanded...C10G, blast furnaces Fulltext... Hierarchy... Expanded...C21B, converters for making steel Fulltext... Hierarchy... Expanded...C21C, furnaces for heat treatment of metal Fulltext... Hierarchy... Expanded...C21D; furnaces for electroslag or arc remelting of metals Fulltext... Hierarchy... Expanded...C22B 9/00; enamelling ovens Fulltext... Hierarchy... Expanded...C23D; combustion apparatus Fulltext... Hierarchy... Expanded...F23; electric heating Fulltext... Hierarchy... Expanded...H05B) [4]

|  | F27 |
Note(s) This class covers: furnaces, kilns, ovens, retorts, open sintering apparatus and other similar apparatus for heat treatment of materials or articles, and details or accessories therefor, in general; the arrangement of electrical heating elements in or on furnaces. This class does not cover: combustion apparatus per se, i.e. apparatus for direct combination of oxygen gas and a burnable substance; [7] electrical heating elements per se; processes carried on within the furnaces. In this class, the following term is used with the meaning indicated: "furnaces" covers kilns, ovens, or retorts.

|  | F27D |
DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE (combustion apparatus Fulltext... Hierarchy... Expanded...F23)

|  | F27D |
Note(s) Attention is drawn to the references and Notes following the title of class Fulltext... Hierarchy... Expanded...F27 and Note III following the Contents of Section of section H.

|  | F27D |
Subclass index
CONSTRUCTIONAL FEATURES | 1/00
HANDLING AND SUPPORTING CHARGE | 3/00, 5/00, 15/00
PREHEATING CHARGE; COOLING; USING WASTE HEAT OR GASES | 13/00; 9/00, 15/02; 17/00
ARRANGEMENTS OF ELECTRIC HEATING ELEMENTS | 11/00
ARRANGEMENTS OF CONTROL AND SAFETY DEVICES | 19/00, 21/00
OTHER FEATURES; OTHER DETAILS | 7/00; 23/00

|  | F27D 1/00 |
Casings; Linings; Walls; Roofs (refractory materials Fulltext... Hierarchy... Expanded...C04B; firebridges for combustion chambers Fulltext... Hierarchy... Expanded...F23M 3/00)

|  | F27D 1/02 |
· | Crowns; Roofs

|  | F27D 1/04 |
· | characterised by the form of the bricks or blocks used

|  | F27D 1/06 |
· · | Composite bricks or blocks

|  | F27D 1/08 |
· · · | Bricks or blocks with internal reinforcement or metal backing

|  | F27D 1/10 |
· | Monolithic linings; Supports therefor

|  | F27D 1/12 |
· | incorporating cooling arrangements (constructions of tube assemblies in general Fulltext... Hierarchy... Expanded...F28)

|  | F27D 1/14 |
· | Supports for linings (Fulltext... Hierarchy... Expanded...F27D 1/10 takes precedence)

|  | F27D 1/16 |
· | Making or repairing linings

|  | F27D 1/18 |
· | Door frames; Doors, lids, removable covers

|  | F27D 3/00 |
Charging; Discharging; Manipulation of charge (conveying systems characterised by their application for specified purposes not otherwise provided for Fulltext... Hierarchy... Expanded...B65G 49/00; moving charge through a furnace Fulltext... Hierarchy... Expanded...F27B 9/14)

|  | F27D 3/02 |
· | Skids or tracks for heavy objects

|  | F27D 3/04 |
· | Ram or pusher apparatus

|  | F27D 3/06 |
· | Charging or discharging machines on travelling carriages

|  | F27D 3/08 |
· | Screw feeders; Screw dischargers

|  | F27D 3/10 |
· | Charging directly from hoppers or shoots

|  | F27D 3/12 |
· | Travelling or movable supports or containers for the charge

|  | F27D 3/14 |
· | Charging or discharging liquid or molten material

|  | F27D 3/15 |
· | Tapping equipment; Equipment for removing slag

|  | F27D 3/16 |
· | Introducing a fluid jet or current into the charge (Fulltext... Hierarchy... Expanded...F27D 3/18 takes precedence) [3]

|  | F27D 3/18 |
· | Charging particulate material using a fluid carrier [3]

|  | F27D 5/00 |
Supports, screens, or the like for the charge within the furnace (travelling or movable supports Fulltext... Hierarchy... Expanded...F27D 3/12)

|  | F27D 7/00 |
Forming, maintaining, or circulating atmospheres in heating chambers

|  | F27D 7/02 |
· | Supplying steam, vapour, gases, or liquids

|  | F27D 7/04 |
· | Circulating atmospheres by mechanical means

|  | F27D 7/06 |
· | Forming or maintaining special atmospheres or vacuum within heating chambers (Fulltext... Hierarchy... Expanded...F27D 7/02 takes precedence)

|  | F27D 9/00 |
Cooling of furnaces or of charges therein (Fulltext... Hierarchy... Expanded...F27D 1/00, Fulltext... Hierarchy... Expanded...F27D 3/00 take precedence)

|  | F27D 11/00 |
Arrangement of elements for electric heating in or on furnaces (electric heating per se Fulltext... Hierarchy... Expanded...H05B)

|  | F27D 11/02 |
· | Ohmic resistance heating

|  | F27D 11/04 |
· · | with direct passage of current through the material being heated

|  | F27D 11/06 |
· | Induction heating, i.e. in which the material being heated, or its container or elements embodied therein, form the secondary of a transformer

|  | F27D 11/08 |
· | Heating by electric discharge, e.g. arc discharge

|  | F27D 11/10 |
· · | Disposition of electrodes (automatic control of temperature Fulltext... Hierarchy... Expanded...G05D 23/00; electric discharge apparatus Fulltext... Hierarchy... Expanded...H01T; arrangements for feeding or guiding electrodes Fulltext... Hierarchy... Expanded...H05B 7/10; automatic control of power by positioning of electrodes Fulltext... Hierarchy... Expanded...H05B 7/144) [3]

|  | F27D 11/12 |
· | with electromagnetic fields acting directly on the material being heated

|  | F27D 13/00 |
Apparatus for preheating charges; Arrangements for preheating charges

|  | F27D 15/00 |
Handling or treating discharged material; Supports or receiving chambers therefor

|  | F27D 15/02 |
· | Cooling

|  | F27D 17/00 |
Arrangement for using waste heat (heat-exchangers per se Fulltext... Hierarchy... Expanded...F28); Arrangement for using, or disposing of, waste gases (removing fumes in general Fulltext... Hierarchy... Expanded...B08B 15/00)

|  | F27D 19/00 |
Arrangement of controlling devices

|  | F27D 21/00 |
Arrangement of monitoring devices; Arrangements of safety devices

|  | F27D 21/02 |
· | Observation or illuminating devices

|  | F27D 21/04 |
· | Arrangements of indicators or alarms

|  | F27D 23/00 |
Details or accessories not covered by any preceding group

|  | F27D 23/02 |
· | Devices for removing incrustations

|  | F27D 23/04 |
· | Stirring devices for molten material (mixing in general Fulltext... Hierarchy... Expanded...B01F) [3]