Improvements in Steam Boilers and Furnaces therefor.
Year: 1888

page_text: Date of Application, 12th Nov., 1889
Complete Specification Left. 12th Aug. 1884-4ccented. 21st Sant 1889
PROVISIONAL SPECIFICATION.
[Communicated from abroad by WILLIAM SPRAGUE POST, of Boston, Machinist,
and HOWARD DE WOLFE SAWYER, of Revere, Engineer, both in Massachusetts,
United States of America.]
Improvements in Steam Boilers and Furnaces therefor.
I, HENRY HARRIS LAKE, of the firm of Haseltine Lake & Co., Patent Agents
Southampton Buildings, in the County of Middlesex do hereby declare the nature of
this invention to be as follows :—
This invention relates to steam boilers and furnaces of the kind described in the
specification of former Letters Patent No. 13,723, dated October 26th 1886.
In the apparatus therein described a downward draught is maintained through
an oblique water-grate, the caloric current being deflected and caused to pass
downwardly below and behind a depending water-leg having an oblique portion
about parallel with the grate, upon which the descending current impinges.
With the present improvements I employ the oblique water-grate and downward
draft, substituting for the dopending leg with its oblique member, a plain, vertical
water-leg with horizontal flues extending rearwardly beyond it, or a vertical water-
back along which the caloric current is deflected to a point considerably below the
grate, passing in either case between water circulating tubes, the said water-back
having, lengthwise through it, a series of vertical tubular flues through which the
caloric current passes upwardly to the funnel. The water-back of the present
upright boiler forms a part of or is connected directly with the water-wall at the
back and each side of the fire box. The pipes of the water-grate run obliquely
downward, and water-circulating pipes below the grate run obliquely upward from the
vertical water-leg or water-back to an independent water-box placed across the front of
the boiler and disconnected from the water-wall theroof. This box may therefore
yield with the expansion and contraction of said pipes, and all may be introduced
together into place through the bottom of the boiler.
In the best form of upright boilers the outer shell is D shaped in horizontal section,
the water-back about semi-cylindrical with the water-grate projecting from its plain
front face and connecting with the water-box located across the flat front of the fire
box just below the feed door. Water walls surround the fire box, and its bottom
may be a water-space, but is preferably left open for insertion of or repairs to
the grate, the boiler in such cases being set upon a fire brick foundation.
The water-back is raised above the bottom of the fire box to give the caloric current
admission to the flues. The water-box may be made in sections each having one or
more grate-tubes and supply pipes connected to it. In some cases said tubes and
pipes are made integral or directly connected by a coupling.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Steam Boilers and Furnaces therefor.
L, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
) Southampton Buildings, in the County of Middlesex, 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:
1-
This invention is in the nature of an improvement upon the apparatus shɔwn in the
British Patent No. 13,723 dated October 26th, 1886.

page_text: In such prior form of apparatus a downward draught is maintained through an
oblique water-grate, the caloric current being deflected and caused to pass downward
below and behind a depending water-leg having an oblique portion approximately
parallel with the grate, upon which the descending current inpinges.
With the present improvements I employ the oblique water-grate and downward
draught, substituting for the depending leg with its oblique member, a plain, vertical
water-leg with horizontal flues extending rearwardly beyond it, or a vertical water-
back along which the caloric current is deflected to a point considerably below the
grate, passing in either case between water circulating tubes, said water-back having,
lengthwise through it, a series of vertical tubular flues through which the caloric
current passes upward to the funnel. The water-back of my present upright boiler
forms a part of or is connected directly with the water-wall at the back and each side
of the fire box. The pipos of the water-grate run obliquely downward, and water-
circulating pipes below the grate run obliquely upward from the vertical water-leg or
water back to an independent water-box placed across the front of the boiler and
disconnected from the water-wall thereof. This box may therefore yield with the
expansion and contraction of said pipes, and all may be introduced together into
place through the bottom of the boiler.
In the best form of my upright boilers the outer shell is D-shaped in horizontal
section, the water-back about semi-cylindrical with the water-grate projecting from
its plain front face and connecting with the water box located across the flat front of
the fire box just below the feed door. Water walls surround the fire box, and its
bottom may be a water-space, but is preferably left open for insertion of or repairs
to the grate, the boiler in such cases being set upon a fire brick foundation. The
water-back is raised above the bottom of the fire box to give the caloric current
admission to the flues. The water-box may be made in sections each having one or
more grate-tubes and supply pipes connected to it. In some cases said tubes and
pipes are made integral or directly connected by a coupling.
In the drawings.
Figure 1 is a vertical section from front to rear of an upright boiler embodying
my improvements.
Figure 2 is a horizontal section on line a, a of Figure 1.
Figure 3 is a perspective view of a horizontal boiler, the present improvement
being shown where the shell is broken away.
Figure 4 represents the water box, grate tubes and circulating pipos, and
Figure 5 is a detail of the same when made in sections.
Describing first the upright boiler represented in figures 1 and 2, and the improve-
ments applied thereto.
A is the outer shell of the boiler, preferably of the D-form in cross-section shown
in the drawings. The fire-box B is placed wholly within this shell, and is divided
by the grate into two chambers C and D, the upper one C, being the fuel chamber
and the lower one the combustion-chamber, in which the gases are consumed.
The fire-box is entirely surrounded by water when in use, except at the bottom,
the space between it and the outer shell forming water-walls E at each side and
in front and rear of the fire box, while the water line is maintained constantly at
a suitable height above the crown-sheet, as shown. The bottom of the boiler may
also be a water space, as shown in Figure 1. A door F above the grate, admits
fuel, and a damper therein constitutes a draught-opening for the downward air-
current, while below it is another door G for removal of ashes. The bottom of
the boiler may be left open for convenience in setting the tubes or for repairs
when the structure rests on a fire-brick foundation.
In rear of the fire-box is the water-back E, constituting a material enlargement
of the water-wall, with which it is directly connected. Through the water-back
vertically there is a series of flues J, for the upward passage of the caloric current,
which is first deflected downwardly by the front wall of the water-back and enters
said flues through the bottom thereof, which is raised a foot or more above the
bottom of the combustion-chamber for this purpose,

page_text: The grate K, upon which the fuel rests, consists of a series of metallic tubes
preferably about one inch in diameter and from one-half to three-fourths of an inch
apart, set parallel to each other and at an inclination of about one inch per linear
foot. Below the grate is another series of water-pipes L shown as larger in diameter
and less in number, inclined in the opposite direction, for the purpose of supplying
water to and maintaining its circulation through the grate. All the tubes K and L
extend from the water-back H forward to and into an independent pipe or water-
hox M, placed horizontally across the front part of the fire-box but detached there-
from, so that it may yield with the tubes under the varying temperatures.
The supply-pipes L thus serve, also, as braces to support the free end of the grate
and the fuel upon it. . The water-box M may be made in sections, as in Figure 5, a
single pipe L supplying water for two or more grate-tubes K.
There are other advantages of our combinations of the grate and supply-pipos with
the water-box M. Said pipes are at first screwed sufficiently far into the box so that
all may be introduced together through the open bottom of the boiler, and when in
position the tubes may be successively unscrewed from the box far enough to enter at
the other end through the front of the waterback and each be thus made fast.
Countersunk set-nuts N, with fire-proof packing, are then employed to secure tight
joints.
By making the box M in sections the tubes connected with any one section may be
readily removed together for repairs, if required, without disturbing the remainder of
the grate.
The downward draught causes the gases evolved to pass through the fire, carries
the caloric current between the tubes of the grate K, impinging upon and passing
between the inclined water-circulating pipes L, and produces in the combustion-
chamber Da most intense heat, to which the water is continually exposed, thus
utilizing the heat to the utmost and generating steam with great rapidity. For more
complete combustion of the gases I arrange to deliver a limited and regulated amount
of air in jets below the grate. An air-pipe P, runs through the foot of the water-
hack and has short hollow nipples Q, connecting its interior withthat of the combustion
chamber, as indicated in Figures 1 and 5, and about as shown in said former Putent
No. 13,723.
Above the flues J is a removable cap or hood, R, so that ready access to said
flues may be had for the purpose of cleaning them when required. A steam pipe S,
and water-inlet W will be furnished with suitable gages, valves &c. The boiler
will be suitably supported by ordinary crown-bars and stay-bolts, so as to have
abundant strength.
In the horizontal boiler Figure 3, the tubes K and L project from the face of the
water-leg and enter the water-box M, which is supported by them and is free
from rigid connection with the side or front walls of the boiler, thus giving
circulation with capability of expansion and contraction as in the upright boilor.
The caloric current after passing between the tubes of both series K and L, and
beneath the water-leg O, traverses the horizontal flues, in the usual way.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondents, I declare that what I claim is :-
First. In a downdraft steam-generator, the fuel chamber C closed tightly at top and
provided with a feed-door and draft-inlet above the grate, and the combustion-
chamber D below the grate, extending beneath the water-back, with the outlet for
O the caloric current through the flues J, in combination with the water-back H,
traversed by said flues, and with the water-grate K, having a front water-connection
and connected with said water-back, substantially as set forth.
Second. In a steam-generator, the shell A, fire-pot B, and deflecting water back H,
having vertical flues J traversing it, in combination with an inclined water-grate K,
5 and a series of water-circulating pipes L, below said grate, adapted to supply water
thereto, for the purpose set forth.

page_text: Third. In a steam-generator, the fire-pot B, having the oblique water-grate K,
saparating the fuel-chamber froin the combustion-chamber, in combination with the
independent water-box M and the water-circulating pipes L, through which water is
supplied to said grate, substantially as set forth.
Fourth. In a steam-generator, the combination of the water-back or water-leg and
independent water-box M, with the water-grate K and oblique circulating-pipes L,
arranged to act as inclined supports for the water-box, suid tubular grate and pipes
both connecting with the water-back or leg and water-box to complete a direct
circulation, substantially as set forth.
234
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.