GB671597A - Furnace comprising coking and combustion grates - Google Patents

Abstract

671,597. Solid-fuel furnaces. SMITH, W. P. April 14, 1950, No. 9212/50. Class 51 (i). [Also in Group XIII] A furnace has a firepot with a grate comprising a coking section and a burning section horizontally aligned the coking section being supplied, from a shoot, with fuel through a discharge opening in an arcuate wall adjacent and above the coking section which is swing- ably mounted at one end, preferably the end adjacent the burning section, the coking section on being swung upwardly its free end travelling in conformity with the curvature of the arcuate wall depositing coked fuel on the burning section, the latter being swingably mounted so that on being swung downwardly burnt residues are dumped. The portion 22 of the firepot 13 is arcuate and extends over the coking section 15 of the grate 14 which section may be swung upwardly on an axis 17 by the operation of a lever 64 to transfer coked fuel on to the burning section 16 of the grate 14, the latter section being swung downwardly on an axis 18 by the operation of a lever 68 when it is desired to dump burnt residues into an ash can 42. The ash pit is divided by a partition 36 carrying a hit-and-miss damper 37 into two compartments 39, 40 both of which house ash cans 42. The ashpit has a door 41 provided with a controlled air inlet 43 for the compartment 39 beneath the burning section 16. Secondary air is supplied through a controlled passageway 47 and ducts 49 in a wall 31 of the firepot 13 to a passage 34 in the neck of the firepot 13 where combustion is completed. The dampers controlling the primary air inlet 43 and the secondary air inlet 47 are interconnected by a chain 44 so that when one is opened the other is closed. Combustion products are circulated in a chamber 35 above the firepot 13 before passing to the chimney, air in a casing 11 surrounding the furnace thus becoming heated. Fuel is supplied from a coal bunker 26 through a shoot 25 and a discharge opening 24 in the arcuate wall 22 of the firepot 13 on to the coking section 15. A door 27 in the shoot 25 is held closed by a counterweight 29 unless fuel is being supplied to the grate 14. Prongs 59, 60 are fitted to opposite ends of a beam 55 pivoted at the middle. On rocking the beam 55 in one direction by a handle 54, one set of prongs are inserted across the shoot 25. By appropriately rocking the beam 55 quantities of fuel may be measured off in the part 50 of the shoot 25 between the prongs 59, 60 and may be discharged into the firepot 13. The two sections of the grate may be covered by additional perforated plates for altering air supply conditions when burning some types of fuel. Combustion gases escape from the chamber 35 by way of a flue 70 to an outlet 72.