IMPROVE- MENTS IN STEAM-BOILERS
Year: 1879

page_text: LETTERS PATENT to Carl Pieper, Civil Engineer and Patent Agent, resident at
74, Belle Alliance Strasse, Berlin, S. W: Prussia, for the Invention of "IMPROVE-
MENTS IN STEAM-BOILERS." A communication by Louis Schwartzkopff, of
Berlin, Prussia; Engineer and Engine Manufacturer.
PROVISIONAL SPECIFICATION left by the said Carl Pieper at the Office of
the Commissioners of Patents on the 17th October 1879.
5177
CARL PIEPER, Civil Engineer and Patent Agent, of 74, Belle Alliance Strasse,
Berlin, S.W. Prussia. IMPROVEMENTS IN STEAM-BOILERS." A communication
by Louis Schwartzkopff, of Berlin, Prussia, Engineer and Engine Manufacturer.
This Invention relates to a special construction of steam-boiler, the object of
which is to obtain with a small weight of boiler.a large heating surface, suitable for
quick and efficient evaporation with a small amount of fuel, and for the production
of dry or superheated steam.
The shell of the boiler and its fire-box have both in horizontal section a rect-
angular shape; the latter being only so much smaller than the former as to leave a
narrow water-space between them. A number of water-tubes passes through the
fire-box, and effects a communication between the water-spaces at the ends of the
boiler. Doors in the shell of the 'boiler give access to the inside of these tubes.
From the crown of the fire-box a series of vertical tubes extends to the top of the
steam-dome. These tubes conduct the combustion-gases into the chimney, and thus
constitute a superheating apparatus.
Larger boilers of this kind may be provided with two or more steam-domes;
having superheating tubes in each of them, and the grate may be divided into
sections by fire-bridges, preferably by so-called water-bridges.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Carl Pieper in the Great Seal Patent Office on the 16th April
1880.
CARL PIEPER, Civil Engineer and Patent Agent, of 74, Belle Alliance Strasse,
Berlin, S.W. Prussia. "IMPROVEMENTS IN STEAM-BOILERS." A communica-
tion by Louis Schwartzkopff, of Berlin, Prussia, Engineer and Engine Manu-
facturer.
This Invention relates to a special construction of steam-boiler, the object of
which is to obtain with a small weight of boiler a large heating surface, suitable
for quick and efficient evaporation with a small amount of fuel, and for the
duction of dry or superheated steam.
pro-
On the annexed Sheet of Drawings this boiler is represented in four different
views, Figs. 1 and 2 being vertical sections at a right angle to each other; Fig. 3,
a horizontal section through the upper part of the fire-box; and Fig. 4, a plan
with section through the steam-dome.
The shell A of the boiler and its firebox B have both in horizontal section a
rectangular shape, the latter being only so much smaller than the former as to leave
a narrow water-space between them; C are water-tubes passing through the fire-
box, and effecting a communication between the water-spaces at the ends of the
boiler. These tubes rise slightly from one end to the other, as usual with similar
tubes, and there are as many of them as can be arranged in the space which is at
disposal for their reception. D, D, are doors in the shell of the boiler, which allow
the tubes to be cleaned inside and to be taken out for renewal when required.
From the plate H rivetted over an opening in the crown of the fire-box a series
of smoke-tubes E extends to the top of the steam-dome K. This dome is of ordinary
design; its top plate I and the plate H are by preference flat on the part in which
the tubes E are fixed. The said tubes conduct the combustion-gases into a chimney
placed on the dome, or connected with the same by a flue, and thus constitute an
efficient superheating apparatus.
The flat parts of the fire-box and of the shell are stayed in the usual manner, so
that they may resist the high pressure for which the boiler is intended. The tube-
plates F, which are also by preference flat, are stayed to the doors D by one or
more stay-bolts G, provided with suitable nuts on the outside, which allow the
doors to be taken off.
The efficiency of the heating surface of this boiler has been proved by experi-
ment, nine pounds of water having been converted in the same into dry steam by
one pound of good coal. The quantity of water contained in the boiler being but
small steam may be raised in a short time.
In proportion to its heating surface it is very light; thus a boiler of this kind
having about 160 sq. ft. of heating surface, and constructed for a pressure of -10
atmospheres, weighed 34 cwt., whereas a locomotive boiler of the same heating
surface and strength would weigh at least 60 cwt. The boiler is therefore specially
adapted for portable engines and for marine purposes. It may be fired with coals,
wood, straw, &c., and also with gas or petroleum.
Larger boilers of this kind, especially when they are made comparatively long, may
be provided with two or more steam-domes K, having a system of superheating
tubes in each of them. It is in this case advantageous to divide the grate in as
many sections as there are steam-domes, and to arrange a fire-bridge (by preference
a so-called water-bridge) between the contiguous sections.
If in addition the chimney (or flue) of each dome is provided with a damper, it
is possible by throwing fresh fuel on the different grates alternately, and by regu-
lating the dampers in suitable manner, to lead the combustion gases from the grate

page_text: provided with fresh fuel over the grates on which the fuel is in a state of incan-
descence, whereby an almost complete consumption or prevention of smoke may be
attained.
The fire-doors may be all arranged on the long side of the boiler, or, if preferred,
those of the outer grates may be at the two ends.
The described fire-bridges between the grates yet afford the advantage of
improving the circulation of water in the boiler, especially if their top is made
sufficiently inclined from one end to the other.
Having thus described the nature and object of this Invention, and the manner
in which it is to be carried out in practice, as communicated to me by the inventor,
I hereby claim as new and essential features of the same,-
1. In a steam-boiler a shell A, fire-box B, water-tubes C, doors D, steam-dome K,
and smoke-tubes E, all constructed and combined substantially as herein before
described with reference to the annexed Drawing.
2. In a steam-boiler the shell A, fire-box B, water-tubes C, doors D, two or more
steam-domes K, with smoke-tubes E passing through each of them, and a grate
divided into one or more sections by fire-bridges, as and for the purpose specified.
In witness whereof, I have hereunto set my hand and seal, this Sixth day of
April, in the year of our Lord One thousand eight hundred and eighty.
CARL DIEDER