IMPROVEMENTS IN STEAM BOILER AND OTHER FURNACES OR
Year: 1882

page_text: LETTERS PATENT to Orel Dighton Orvis, a resident of the City, County and
State of New York in the United States of America, Gentleman for an
Invention of IMPROVEMENTS IN STEAM BOILER AND OTHER FURNACES OR
PROVISIONAL SPECIFICATION left by the said Orel Dighton Orvis at the
Office of the Commissioners of Patents on the 6th December 1882.
OREL DIGHTON ORVIS a resident of the city, county and state of New York,
in the United States of America, Gentleman "IMPROVEMENTS IN STEAM BOILER
AND OTHER FURNACES, OR IN ACCESSORIES THEREOF, FOR PROMOTING PERFECT
COMBUSTION
"
My Invention relates to furnaces in which are arranged one or more pipes or
nozzles opening into the fuel chamber above the burning fuel, through which
nozzles combined jets of steam and air are introduced into the chamber with
considerable force, in order that they may commingle with the heated gases rising
from the bed of fuel, and supply the necessary oxygen and bydrogen for consuming
the said gases and promoting perfect combustion.
In efforts to improve the combustion of fuel by means of such combined jets of
air and steam, it has been found that the best effects are produced by injecting the
jets in close proximity to the bed of fuel, and in a horizontal direction but the air
current supplied to the injector is usually only at a nominal temperature, so that the
temperature of the steam is somewhat reduced, and hence the combined jet when
entering the furnace is not at as high a temperature as is requisite to produce the
most successful results, as the reduced temperature of the jet correspondingly
reduces the temperature of the burning gases, and so retards their combustion, and
impedes the union with them of the constituents of the jet.
The objects of my Invention are, to provide means for heating the air before its
contact with the blast of steam; to control or regulate the proportions of air and
steam injected, and the force of the blasts; and consequently to attain as effectual
a combination of the constituents of the jets with the gases rising from the fuel, as
011...מ

page_text: complete a suppression of smoke, and as perfect a utilization of all the heat pro-
ducing power of the fuel as possible, and finally to obviate the noise usually attending
the operation of the injectors.
The furnace to which my Invention is applied may be of any usual or known
construction, and employed for any purpose desired. I arrange the inlet tubes or
nozzles in pairs, usually one pair being arranged at each side of the furnace,
extending through its front wall and opening into the fuel chamber adjacent to the
side walls thereof.
The nozzle of cach pair nearest the side wall projects into the fuel chamber
parallel to that wall, while the other one is bent toward the centre of the chamber,
so that the jets from these two bent nozzles on opposite sides of the chamber con-
verge and meet each other at à point about midway of the two side walls, and
about two thirds of the distance from the front to the back of the grate surface.
The straight pipes next the walls serve to supply the necessary oxygen and
hydrogen to the gases rising along each side of the chamber and cause them to
ignite, instead of rising as they otherwise would to the space between the sides of
the boiler and the furnace walls where, becoming chilled, they would pass out from
the furnace partially unconsumed. The converging nozzles serve to supply a
double amount of oxygen and hydrogen over the central and hottest part of the
fuel chamber, and especially at the point of their inter-section, where the combustion
is more rapid and the products at a higher temperature than elsewhere.
A third pair of nozzles may be arranged in the centre of the front wall midway
of the two at the sides, in which case it is preferable to bend them from each other
'so that their jets shall diverge toward the sides of the chamber.
All the nozzles are preferably arranged horizontally, and in a plane about level
with the top of the bridge wall, rising at the rear of the grate, as the most perfect
combustion is thus attained, and the greatest acceleration of the draft is
produced.
The
I will now describe the form of injector which I have devised. All the nozzles
on the inlet-pipes project through the front wall, and on their projecting ends
vacuum chambers are fitted. There is one vacuum chamber to each pair of nozzles,
and each vacuum chamber is formed of a retangular metallic box, into holes in the
rear side of which. nozzles fit, the box being fixed to them by set screws.
front portion of the box is formed with two inverted T shaped chambers or
cavities, the horizontal portions or passages of which are in line with the axes of
the parallel portions of the nozzles, and extend from the front of the box to the
vacuum cavity in its interior. From the intermediate portion of each of these
.horizontal passages, the vertical portion extends, and opens at the top of the box,
where a small steam pipe is screwed into it. These several small steam pipes are
all branches of a pipe leading from a boiler over the furnace (or from any other
convenient source of steam) which it should tap at the upper part or steam dome,
where the steam is dry. This pipe is fitted with a cock or valve to regulate the
passage of steam through it. Each of the horizontal passages in cach box is fitted,
where it opens into the vacuum cavity with a steam nipple or jet-tube which is
screwed into the passage and projects rearwardly through the said cavity toward
the inlet nozzle to the furnace. The front end of the horizontal passage is closed
by a screw plug, upon removing which the interior of the nipple is accessible for
cleaning. Thus the steam from the boiler passes, through the pipes to the two
Tshaped passages down to the vertical limbs thereof and thence to the rear through
their horizontal limbs and through the jet nipples across the vacuum cavity and
into the inlet nozzles. The top of the box is provided with a hinged lid by raising
which the vacuum chamber is opened and rendered accessible
"
At the bottom of the vacuum cavity and directly beneath; the nipples are two
holes through the box into which are fitted the upper ends of two air pipes, which
extend thence vertically down along the front wall of the furnace and pass through
the said wall into the ash pit through which they extend rearwardly close beneath
the grate to near the rear end of the same, their rear ends being left open. Around

page_text: these pipes is placed a larger tube, which I call a casing, and which extends from the
front of the furnace where its end is open, back through the ash pit close beneath
the grate to just beyond the rear ends of the two air pipes, where its rear end is
closed. Air is drawn by the suction in the vacuum chamber through this casing
from front to rear, into the air pipes and through them to the vacuum chamber,
whence it is drawn into the nozzles and is injected with the steam into the fuel
chamber. The casing and its, enclosed pipes because of their close proximity to the
grate, are kept, highly heated and the air in passing through them is raised to a
high temperature the result being that the steam is not materially cooled by
mingling with it, and the combined jet as it enters the furnace has so high a
temperature that its union with the gases of combustion is rendered rapid, complete
and effectual.
The air heating casings may project into or through the bridge wall if desired,
and instead of being suspended in the ash pit may be imbedded in the walls of the
furnace adjacent to the bed of burning fuel, or wherever it will become sufficiently
heated to impart to the air the requisite degree of heat. Or the casing may be
entirely omitted, and the air pipes be bent upon themselves at their back ends, and
extended to the front of the furnace, to the same effect so far as the heating of the
air is concerned, but the use of the casings is preferable as it protects the air pipes
from injury and deadens the noise caused by the air rushing into the inlet pipes.
There may be but one air inlet pipe to each vacuum chamber, instead of two, if
freferred.
My Invention is well adapted for application to Lancashire boilers and other
types of boiler, furnaces and also to the furnaces of locomotive engines. Although
primarily designed to promote the perfect combustion of bituminous fuels, its use is
particularly advantageous with furnaces where anthracite coal is burned, as the
fuel is thereby much more, economically utilized.
0

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Orel Dighton Orvis in the Great Seal Patent Office on the 24th May
1883.
OREL DIGHTON ORVIS a resident of the city county and State of New York, in
the United States of America, Gentleman "IMPROVEMENTS IN STEAM BOILER
AND OTHER FURNACES, OR IN ACCESSORIES THEREOF, FOR PROMOTING PERFECT
COMBUSTION
"
My invention relates to furnaces in which are arranged a series of pipes opening
into the fire-chamber above the burning fuel, through which pipes are introduced
with considérable force combined jets of steam and air designed to commingle with
the heated gases arising from the fire-bed and supply the requisite oxygen and
hydrogen for consuming said gases and promoting perfect combustion.
In efforts to improve the combustion of fuel practical experiment has demonstrated
that the injection of jets of combined steam and air in close proximity to and in a
horizontal plane over the burning fuel in a furnace produces the best effects but
usually the air current supplied is at a normal temperature as it comes in contact
with the steam before the two are combined and injected into the furnace, so that
the temperature of the steam is somewhat reduced and hence the combined jet of
steam and air when entering the furnace is not at as high a temperature as it
should be to effectually commingle with and ignite the gases.
This reduced temperature of the jet correspondingly reduces the temperature of
the gases, or rising products of combustion as they are more properly termed, which
should not be the case, at least to any marked degree, for such gases will only
ignite when at a very high temperature, in fact so high that they are chilled below
it before coming in contact with the crown sheets of a boiler, where they form a
stratum seriously obstructing the effectiveness of the burning fuel.
Experiment has also demonstrated that it is not only necessary to have the
proper proportion of steam and air composing the jets, but that the volume of the
jets should be increased or diminished proportionately to the area and intensity of
heat of the fire-bed, as for instance when firing up and fresh fuel is added to an
incandescent bed of coals, the combustion of the fresh fuel is much more rapid than
that of the incandescent bed, hence the volume of the jet should be increased
correspondingly to efficiently consume the rapidly rising products of combustion,
while on the other hand an excessive volume from the jets on the incandescent bed
would be unnecessary and a waste of steam.
It is not only desirable in steam boiler furnaces to prevent smoke and the
escape of noxious gases by consuming the waste products of combustion but to
generate the greatest amount of steam with the least amount of fuel, and hence it
is desirable to economize the steam injected to promote combustion.
The objects of my invention are therefore to provide means for regulating and
more nearly supplying the requisite proportions and volume of steam and air to a
furnace, to heat the air before its contact with the steam; to effectually and
thoroughly commingle the air and steam of the jet with and ignite the rising and
otherwise waste products of combustion from the fire-bed, and thereby attain a
combustion so nearly perfect as to prevent the formation of smoke and the escape
from the furnace of gases deleterious to the health and comfort of the persons in
the vicinity of the furnace; to produce a maximum amount of steam with a
minimum amount of fuel; and finally to not only economically heat the air before
contact with the steam jet, but at the same time to obviate the noise usually
attending the rushing of the air to the furnace.

page_text: 1 attain these objects by devices illustrated in the accompanying drawings
wherein :-
Figure 1 is a vertical longitudinal section cut in the plane of the line 1-1 in
Figure 2, of the front portion of a stationary boiler and furnace of ordinary
construction fitted with my invention; Figure 2 is a horizontal section of the saine
cut in the plane of the line 2-2 in Figure 1; Figure 3 is a vertical section of a
vacuum chamber forming part of my invention, cut in the plane of the line 3-3 in
Figure 4; Figure 4 is a horizontal section of the same, cut in the plane of the
line 4-4 in Figure 3; Figure 5 is a front elevation of a Lancashire boiler and
furnace provided with my invention; and Figure 6 is a side view of a locomotive
boiler and furnace provided with my invention, shown partly in vertical longitudinal
mid-section.
Referring to Figures 1 and 2, F is the boiler and G is the fuel or combustion-
chamber of the furnace, of which H is the front-wall, ff is the grate or fuel-bed,
I is the ash-pit and g is the bridge-wall at the rear of the grate. In Figure 2 the
grate is shown as broken away at each side in order to expose to view two air-
tubes J J which I shall refer to as casings, and these casings are shown partly in
section, in order to render inner pipes E E visible. The tubular casings J J are
placed close beneath the grate, and are closed at their rear ends and open at their.
front ends. Two of the smaller pipes E E extend into each of the casings J J to
near the rear ends thereof and their inner ends are open. Their outer ends project
beyond the front of the furnace, and extend thence upward to and connect with a
vacuum chamber A. There are as many of these chambers as there are casings J,
three being shown in Figure 2. A steam-pipe C leads from the boiler or one of the
boilers, is fitted with a regulating-cock h, and connects with branch-pipes C' C' each
of which leads to one of the vacuum chambers A. The pipe C should tap the
boiler at its upper part or dome so as to take off as dry steam as possible, as that is
best adapted for the purpose to which I apply it.
The vacuum chamber A is shown in detail in Figures 3 and 4 and consists of a
rectangular box provided with a hinged lid or cover a for convenience of access to
its interior, and formed with two inverted T-shaped chambers d, the vertical
portion of each of which opens at the top of the box, while the horizontal portion
opens at the outer front side and the inner front side. The inner openings have
bosses projecting into the cavity of the box, into which bosses are screwed steam jet
nipples B B, which project in a horizontal direction beyond the center of the box
and in a line with the axes of the discharge nozzles, or inlet pipes D D
The outerside openings of the chambers d d are closed by screw-threaded plugs c
and into the vertical openings are screwed the steam-pipes C¹ C₁ which thereby
connect through the chambers d d with the two jet nipples B B.
The particular form of the chambers d admits of conveniently casting them with
the vacuum chamber and permits the steam pipes, jets and plugs to be so connected
as to be removed at any time for repairs or for extracting any foreign substances
which may accumulate in the chambers & or the jets.
The inlet-pipes 1) D are imbedded in a horizontal plane in the front wall H of
the furnace, in a plane slightly above the bed of fuel, and project on the front side
of the wall to provide for the attachment of the vacuum chamber A into which
they enter and are held by set screws e e (see Fig. 4). These pipes D D project
on the inner side of the wall in the manner shown in Fig. 2, those nearest the side-
walls of the furnace (lettered D' 1') extending in a line parallel with said walls and
those adjoining them (lettered D2 D³) being bent toward each other at an angle so
that their jets will intersect at the point x at the center of width of the grate f, but
slightly back of or beyond its center of length, as shown.
In addition to the two side-chambers A A and their inlet-pipes D' D* I have in
Figure 4 shown a third chamber arranged between the furnace doors and having
diverging pipes D³ D³ to throw jets as indicated in dotted lines, but this may be
omitted at pleasure. I do not limit myself to any particular number of vacuum-

page_text: chambers or inlet pipes although it is essential for practical purposes that at least
two should be employed near the respective sides of the furnace.
:
By having the straight inlet-pipes D₁ next tlie side of the furnace I am enabled
to supply the products of combustion which rise along the sides of the furnace with
the necessary oxygen and hydrogen to cause them to ignite whereas otherwise
these gases would ascend to the space existing between the sides of the boiler and
the furnace, where, becoming chilled, they would escape from the furnace in the form
of smoke and unconsumed gases. The converging pipes D2 D2 serve to supply a
double amount of oxygen and hydrogen over the central and hottest portion of the
furnace and especially at the point where combustion is more rapid, and the
products are at a higher temperature than at any other point.
•
It will be observed by referring to Fig. 1, that the inlet pipes are arranged in
a plane on about the top of the bridge-wall 9 and while this arrangement is
preferable for the reason that the rising products escaping over the top of the
bridge-wall are the hottest of the escaping products, and hence more readily ignited
by the jets of steam and 'air. I do not limit my invention to this exact arrange-
ment of the inlet-pipes, for they may be arranged below the top of the bridge-wall,
though preferably above, for the reason stated, and for the further reason that the
draft is thereby augmented.
As before intimated the best effects are attained by the arrangement of the inlet
pipes in a plane above and in close proximity to the burning fuel upon the grate
bars, but this with the other effects just mentioned may be produced by having
the bridge-wall extending above the grate bars a height corresponding with the
contemplated depth of fuel to be employed.
By having a common vacuum chamber for the two inlet-pipes D1 D2 a corre-
sponding saving in material and number of vacuum chambers is attained and
furthermore less space on the front of the furnace for a given number of inlet-pipes
is required for the vacuum chambers.
The pipes E E are tapped into the bottom of the vacuum chamber A directly
under the jets B B and serve as air inlet pipes. The air passes from the front of
the furnace back through the casing J, being heated in consequence of the position
of the latter close under the grate, and it then enters the pipes E E through which
it flows to the front, being therein further heated and thereby raised to a very
high temperature before ascending to the vacuum chamber and coming in contact
with the steam jets to which it is drawn by the vacuum created in the vacuum
chamber by the steam rushing from the jets to the inlet-pipes.
In this connection it may be noted that by having the jets extending over the
air supply pipes towards the rear of the vacuum chamber that portion of the
chamber toward the butts of the jets is made to contain a vacuum in excess of
what there would be if shorter nipples were employed, and as a result a greater
volume of air under a stronger pressure is forced into the furnace with a given
amount of steam.
So far as heating the air in the air-supply pipe is concerned, the same result may
be obtained by bending the pipe E upon itself and returning the end towards the
front of the furnace, but by employing the casing J several highly important
results are obtained, namely, that of protecting the inlet pipe from the destructive
influences of the heat, of rendering it less liable to become clogged with foreign
substances, and pricipally that of deadening the noise caused by the air rushing
into the inlet-pipes for as will be seen the air must first reach the rear portion of
the ash-pit or closed end of the casing before becoming subject to this objection,
hence the noise created is deadened inside of the furnace and thereby affords little
or no annoyance to the attendant.
The casing J may project into or through the bridge-wall if desired, and instead.
of being suspended in the ash-pit may be imbedded in the walls of the furnace, or
in division walls dividing the ash-pit and supporting two or more sets of grate-
bars arranged-side-by-side as frequently happens in the larger class of furnaces or

page_text: in any other convenient manner to effectually heat the air before entering the air-
supply pipe, but ordinarily the degree of heat in the ash-pit is sufficient for this
purpose, if the casing is suspended sufficiently close to the grate bars.
By heating the air before contact with the steam the jet in the furnace is at a
higher degree of heat than if the air were taken at its normal temperature, hence
the jet more readily commingles with and ignites the rising products than if at a
lower temperature, and consequently there is no perceptible escape of gases or smoke
from the furnace
My invention is particularly adapted to furnaces in which anthracite or hard
coal is employed, for while there is little or no smoke the volume of gases is very
great and I am not only enabled to consume these gases but to effectually provide
an adequate draft, which would not be the case if the air injected were at the
normal temperature or even though partially heated by the jet of steam.
In Figure 5 is illustrated the adaptation of my invention to a Lancashire boiler,
showing double jets upon each side of the two furnace doors.
I have also shown in Figure 6 the adaptation of my invention to the furnace of
a locomotive engine, but desire to have it understood that it is equally applicable
to any furnace, whether or not a boiler is used, though in the latter case a steam
generator should be employed and connected with the jet in the furnace.
Having thus fully described and ascertained the nature of my said invention, I
hereby declare that what I claim and desire to secure by letters patent is :-
First The described arrangement of the air and steam inlet nozzles in pairs,
each pair connected with one vacuum chamber, as and for the purposes set forth.
Second-The described arrangement of the air-heating pipes E E or of a
single pipe, in the casing J, and their connection with the vacuum chamber A, and
pair of nozzles D D
Third A furnace provided at each side with a pair of air and steam injecting
nozzles D D, the nozzle D¹ at each side directed parallel with the side walls, and
the nozzles D2 D2 directed toward cach other, so that their jets converge and
intersect at or near the point x, substantially as described.
Fourth-The described construction of the vacuum chamber A, with passages or.
cavities & d, jet nipples B B, inlet nozzles D D, and air-pipes E, in substantially the
manner set forth.
Fifth-The box A formed with passages dd, nipples B B screwed thereinto,
the screw-plugs e e, and the hinged lid a, substantially as set forth.
In Witness Whereof I the said Orel Dighton Orvis, have hereunto set my
hand and seal this fifth day of May in the year of our Lord 1883, in the
city of New York. U.S.A.
OREL DIGHTON ORVIS (L.S.)
In the presence of
ARTHUR C. FRASER
Solicitor of Patents, at No. 10 Spuce Street, New York.