Improvements in Steam Boilers.
Year: 1894

page_text: Date of Application, 25th July, 1894-Accepted, 8th Sept., 1894
Improvements in Steam Boilers.
I, JOSEPH PRÉGARDIEN of Deutz, near Cologne, Germany, Boiler Maker
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 :-
This invention relates to such improvements in steam boilers by which I am
enabled to use the well known Tenbrink grate for boilers of any size. The special
arrangement of the Tenbrink grate limits the same to a rather small surface of the
grate, and notwithstanding its good qualities for economy of fuel the Tenbrink
grate has not been so generally introduced as it is disirous,- because the grate
surface could not be enlarged in proportion to the increase of the heating surface
required for large boilers. I have overcome this difficulty by the boiler shown in
the accompanying drawing and described hereafter.
Figure 1 is a vertical section along line 1-I of Figure 2;
Figure 2 is a horizontal section along line II-II of Figure 1 ;
Figure 3 is a vertical cross section along line III-III of Figure 1;
Figure 4 is a similar section along IV-IV of Figure 1.
The boiler consists of two or more sections 1, 1, 2 II. . . according to the power
of the boiler, placed one behind the other. These sections or elements are
composed each of a lower water drum 1, 2.... and a steam and water
drum I, II... which are connected by bundles of water circulating tubes 3, 4 ....
and by connecting tubes 5, 6.
The two drums of each section are also connected by large vertical tubes 7, 7; 8,8
at both sides of the boiler.
Each section or element forms a small tubular boiler arranged crossways to the
direction taken by the heating gases. This has for its object that the Tenbrink grates
can be arranged in front of the first element in any number side by side as may be
required by the size of the boiler.
According to the heating surface I arrange two, three or more grates 9, 99 side
by side (three are shown in the drawing).
In order to avoid that the piercing flame coming direct from the grate strikes
directly against the circulating tubes 3 and also for the sake of directing it more
upwards towards the water tube 11, arranged in front of the first element, I provide
the fire bridge 10.
Above the tube 11 is a similar tube 12 communicating with the other one by
tubes 13. The tube 12 is joined to the upper drum I by horizontal tubes 14 on both
sides and it is also provided with a head 21 to which are fitted the fittings (pressure
gauge, gauge coks, water gauge etc.) not shown on the drawing.
Below the grate I arrange the feed tube 15 communicating with the tube 11
above by means of the tubes 16 and being also connected to the lower water drum 1
of the first element by means of a tube 17, shown in dotted lines in Figure 2; 18 is
a stay joining the tube 15 and the drum 1 at the other side; 19 is a cast pipe for
attaching the feed valve and 20 is an outlet pipe.
Between the two drums 1 and 2 I arrange the flap valve 22; by means of which
I can regulate and alter the current of the heating gases.
goes
The feed water is fed into the tube 15 through the feed pipe 19; from 15 it
upwards through the tubes 11, 13 and 12 and thence it passes on through 14 into
the drum I; at the same time part of the water goes through the pipe 17 into the
lower drum 1, rising up through the tubes 7 and the circulating pipes 3, thus filling

page_text: the first element. Through the connecting spipes 5 and 6 the second element is
filled and so on, when there are-more.
The heating gases produced on the separate grates 9 go upwards, past the
tube 11, then along between the circulating tubes 3 and the drums 1, I and
between 2, II and the tube bundle 4 round the drum 2 downwards and past the
lower part of the drum 1 into the chimney; the bridge 28 thereby forcing the
stream upwards and to strike against the drum 1. The flap valve 22 is hereby
closed or put in a horizontal position. If however it is desired to slack the steam
production, the valve 22 can be set vertically and then the heating gases partly go
out between the two drums 1 and 2 as indicated by the arrow.
The grates are separated by partion walls 26 into which are built air inlet holes,
channels 25 for causing a free admission of air into the fire.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
An arrangement of steam boilers permitting the use of Tenbrink grates for any
width of the boiler and for any size of heating surface by constructing the boiler of
separate elements 1, 1, 3; 2, II, 4 and so on put crossways to the single grates 9
and communicating with each other by connecting tubes 5, 6; a fire bridge 10 and
a tube 11 above the grate leading the heating gases to pass along between the
large drums 1, I, 2 II and the circulating tubes fixed between these.
Dated this 21st day of July 1894.
JOSEPH PRÉGARDIEN,
Per Karl J. Mayer,
Agent.