Improvements in Steam Boilers, and Furnaces therefor.
Year: 1897

page_text: Date of Application, 18th May, 1897-Accepted, 19th June, 1897
COMPLETE SPECIFICATION.
Improvements in Steam Boilers, and Furnaces therefor.
I JOSÉ FRANCISCO DE NAVARRO of No. 143 Liberty Street in the City of
New York in the State of New York, United States of America, Merchant do
hereby declare the nature of this invention and in what manuer the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to the application to the under part of a boiler, which is
exposed to the heat of the fire, or of the ignited products of combustion, of a shield
of refractory material, as fire-brick, for the purpose of protecting the surface of
the plates of the boiler from injury by the too intense action of the heat; and the
improvement consists in the construction of and means for supporting such a shield
as hereinafter described and claimed.
Fig. 1 in the drawing represents a central longitudinal section of part of a boiler
and its furnace having my improvement applied.
Fig. 2 represents a transverse section on the line 2-2 of Fig. 1.
Fig. 3 a side elevation, with part of the side well removed, and with certain parts
in section, on the line 3-3, of Fig. 2;
Fig. 4 a transverse section in the line 4-4 of Fig. 1.
Figs. 5, 6, and 7 represent, on a larger scale than Figs. 1 to 4, certain details
which will be hereinafter explained.
A is the boiler, which may be supported in the usual manner, and is represented
as so supported, at its sides by saddle plates B, B on the side walls C of the furnace,
and by a frout wall B' and front plate B³.
D designates the shield composed of bricks of any suitable length, width, and
thickness, abutting together at their sides and ends, and forming together an
inverted arch conforming to the under part of the boiler, and fitting closely, or
approximately so, to the boiler. The bricks are represented in Fig. 2 as tongued
together, but this is not material.
E, E are arches of masonry arranged crosswise of the boiler, between the side
walls C of the furnace or front portion of the boiler setting, at suitable intervals
apart, for the support of the shield D, the distance between the said arches, and
the length of the bricks, being so proportioned, that the abutting ends of the bricks
in the lower part of the shield are supported directly upon the crowns of said
arches, as may be understood by reference to Figs. 1 and 2.
On each of the said arches between it, the shield, and the side walls C of the
boiler, are two upright plates F of refractory material, as fire clay, of approximately
triangular form, as may be understood by reference to Fig. 2, for supporting the
shield towards the sides thereof, one edge of said plates conforming to the shield,
another conforming to the arch E, and the third edge abutting against the adjacent
side wall. These plates may be perforated with any number of holes, but are
represented as each having a large hole a and two openings formed between it and
the adjacent side wall-by recesses bin its sides. One of the said plates is shown in
Fig. 3 as in section taken on the line 3-3 of Fig. 2, and an edge view of the other
is shown as exposed by the breaking away of the side wall.
Though I prefer to use the supporting arches E, E of masonry for the support
of the shield D in the front portion of the furnace or boiler setting, where the
heat is most intense, I propose in the rear portion to suspend the shield D, D

page_text: directly from the boiler itself, as shown in Figs. 1, 2, 4, by bands H, H of
steel or iron, which encircle the body of the boiler and the shield, the said
bands being represented as passing through mortises h formed transversely in
the bricks.
In the example shown in Figs. 1, 3, 4, 5, and 6, the mortises are at a distance
from the ends of the bricks, and only open at the sides thereof. In the example
shown in Fig. 7, the mortises are in the ends of the bricks, and are opeh at the ends,
permitting the bands to be inserted laterally from the ends of the bricks, while
in the example shown in Figs. 1, 3, 4, 5, 6, the bands must be run endwise through
the mortises. The bands are each open in that part which comes upon the crown
of the boiler, and provided with lugs i, through which are passed a screw bolt c,
threaded, and furnished with nuts dat each end, for the purpose of drawing up
the band as tight as may be desired, through the bricks of the shield, and around
the boiler. Between the nuts d. and the lugs i, coil springs e are applied, which
compensate for the contraction and expansion of the bands by variations of
temperature, and keep them tight without danger of their bursting, or of the
bricks being injured by them.
In order to provide for the passage of the bands through the mortises constructed
as illustrated by Figs. 1, 2, 3, 4, one or both of the lugs i must be removably
attached to the band. In Figs. 1 and 2, both are shown as so removably attached
by a screw f.
This invention is more especially intended for furnaces in which pulverized fuel
is introduced with a blast of air, and the example represented, so far as it is
illustrated in Figs. 1 and 2 in bold outline, and in Fig. 3, is designed for such fuel
only, the said fuel with the blast of air being introduced under the front part of
the boiler through a pipe G. The incandescent particles of fuel, and the inflamed
gases resulting therefrom, have a free passage through the arches E and through
the openings ab of the plates F, and free circulation between the arches, so that
they pass under the boiler with no more obstruction than is desirable to keep
them long enough in contact with the shield D, for the transmission through it
to the boiler, of all their available heat, while the metal of the boiler is protected
by the shield from the injurious effects of the intense heat generated from such
fuel.
In Figs. 1 and 2, there are represented in dotted outline,-under the front part of
the boiler as far as the second arch E,-a fire grate I, having an ashpit J below it,
illustrating the adaptation of the invention to a boiler furnace for solid fuel. For
the use of solid fuel, the slabs K of fire clay, represented in Figs. 1 and 2 as forming
the bottom of the arches, will be omitted. By providing the grate and ashpit as so
represented, and making the said slabs removable, convenience will be afforded for
the use of either solid or pulverized fuel, as may be desirable, and, in a furnace
intended to be used generally for pulverized fuel, the grate and ash-pit will permit
solid fuel to be used in case of any disorganization of the apparatus for supplying
pulverized fuel.
The shield D may extend under any portion of the length of the boiler. While
the supporting arches E and plates F may be used under the front portion of the
boiler, and the suspending bands H under the portion farther back, as in the
example represented, in some cases the said supporting arches and plates might be
used at suitable intervals throughout the whole length of the shield, and in some
cases the suspending bands might be used at intervals throughout the whole length
of the shield.
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 :-
:-
1. In a boiler furnace, a shield for the under part of the boiler, consisting of an
inverted arch formed of bricks of refractory material conforming to the boiler,
open arches arranged crosswise of the boiler, and supporting the bottom of said

page_text: shield at intervals, and upright supporting plates arranged crosswise of the boiler,
between the said open arches and the said shield, for supporting the latter between
the said open arches and the side walls of the furnace, substantially as herein
described.
2. In a boiler furnace, a shield for the under part of the boiler, consisting of an
inverted arch of refractory material conforming to the boiler, open arches arranged
crosswise of the boiler, and supporting the bottom of said shield at intervals, and
upright perforated supporting plates arranged crosswise of the boiler between the
said shield and open arches and the side walls of the furnace, substantially as herein
described.
3. In a boiler furnace, a shield for the under part of the boiler, consisting of au
inverted arch formed of bricks of refractory material abutting together, open
supporting arches arranged crosswise of the boiler directly under the abutting end
portions of adjacent bricks, and upright supporting plates arranged crosswise of the
boiler, between said open arches and shield and the side walls of the furnace, and
opposite the abutting end portions of adjacent fire bricks, substantially as herein
described.
4. The combination with a boiler, of a shield for its under part, consisting of an
inverted arch of refractory material, and metal bands encircling both the said shield
and the boiler, for the suspension of said shield from the upper part of the boiler,
substantially as herein described.
5. The combination with a boiler, of a shield for its under part, consisting of an
inverted arch formed of mortised bricks of refractory material conforming to said
part, and metal bands passing through the mortises of said bricks and encircling the
boiler, substantially as herein described.
6. The combination with a boiler, of a shield for its under part, consisting of an
inverted arch of refractory material, open metal bands encircling both the said
shield and the boiler, for the suspension of said shield from the upper part of the
boiler, means for drawing together the open ends of said bands, and springs applied
at said ends, to compensate for expansion and contraction, substantially as herein
described.
1
SM 1007
NEWTON & SON,
Agents for the Applicant.