Improvements relating to Grates for Furnaces.
Year: 1899

page_text: Date of Application, 1st Mar., 1899-Accepted, 17th June, 1899
COMPLETE SPECIFICATION.
Improvements relating to Grates for Furnaces.
I, PAUL CORNELIUS, Manufacturer, of 13, Friedrichsstrasse, Berlin, in the
Empire of Germany, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:-
A complete and uniform oxidisation or combustion of the combustible gases
is seldom attained and more especially in the grates of furnaces which are rela-
tively long. This defect is still greater if the air serving for combustion flows
through a restricted space where it is gradually heated. This results from the
fact that the atmospheric air used for the purpose of combustion is increased
in volume by increase in temperature, and when thus expanded, no longer
introduces sufficient oxygen through the air supply orifices. This defect is
particularly experienced in long grates where a considerable excess of air may
predominate in the front of the bars, while in the rear insufficient air is present
for complete and effective combustion. Means for more thoroughly admixing
the partially burnt gases with air has hitherto not resulted in the complete
combustion required. The object of the present invention is to secure complete
combustion in furnaces generally and especially such as described in the Specifica-
tion of Letters Patent No. 159 of 1898.
According to the invention the air is uniformly distributed throughout the
length of the grate, so that throughout the fire, the gases find sufficient amount
of oxygen for complete combustion, a greater quantity of air being admitted
towards the rear of the grate.
I make good the increase in volume to which the air is subjected towards the
rear of the fire, and for this purpose the air supply orifices or intersticial spaces
of the grate bars are made larger towards the rear.
The invention is illustrated in the various modifications in the accompanying
drawings-
Figure 1 represents in plan bars provided according to the invention of a form
tapered towards the rear extremity.
Figure 2 represents in plan tubular bars provided with openings which become
larger towards the rear.
Figure 3 represents in perspective plan a tubular grate bar having lateral
openings.
Figure 4 illustrates in perspective plan a modification in design of a tubular
grate bar similar to that represented in Figure 3, which has upper instead of
lateral air admission orifices.
In carrying the invention into effect as illustrated in Figure 1 each grate bar
has a stem a which is broader at the front end 6 than at the rear end c so that
the intersticial space becomes wider towards the rear, and therefore more air may
flow in towards the rear than in the front.
Figure 2 represents a modification in which hollow grate bars are employed
having a well known shape and formation. These bars have either air inlet

page_text: orifices e provided in their lateral faces as represented in Figure 3, or upon the
top as in Figure 4, such orifices being gradually larger towards the rear end of
the grate bar. It will be understood that in these hollow grate bars air for sup
porting combustion passes through the hollow interior space and thence through
openings into the super-incumbent layers of coal.
The air may be forced by means of a fan, or an induced draft may be applied
so as to effect more vigorous combustion. Inflammable liquid such as naptha
may be forced through to augment combustion.
Having now particularly described and ascertained the nature of my said in-
vention, and in what manner the same is to be performed, I declare that what I
claim is:-
1. In grates, the method of effecting uniform and complete oxidisation of the
combustible gases, where the air or other oxidising medium is subjected in its
passage to increase of temperature, consisting in the formation of the air supply
inlets, or intersticial spaces between the bars of the grate, gradually larger
towards the rear for the purpose described.
2.-Means for effecting a uniform and complete oxidisation or combustion
of the combustible gases in grates for the purpose and substantially as herein-
before described and illustrated.
MARKS & CLERK,
18, Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and 25, Cross Street, Manchester, Agents.