Improvements in. Boller Tube Attachments.
Year: 1894

page_text: Date of Application, 11th Sept., 1894
Complete Specification Left, 4th June, 1895-Accepted, 13th July, 1895
Improvements in. Boller Tube Attachments.
A communication from CHARLES WILLIAM WHITNEY, of 64, 66 and 68 Broadway,
New York City, United States of America, Commission Merchant.
I, ALFRED JULIUS BOULT, of 323 High Holborn, London, in the County.of
Middlesex, Chartered Patent Agent, do hereby declare the nature of the said
invention, and in what manner the same are to be performed, to be particularly
described and ascertained in the following statement :-
The object of my invention is to provide a device for distributing or circulating
the heated gases in tubular boilers, so that instead of their passing through the
tubes in solid bodies, into which they are usually drawn by the action of the draft,
they will be broken up and forced into contact with the walls of the tubes, thereby
more certainly utilizing the heat they contain before it passes out of the tube and
into the smoke-stack, the vast majority of the heat being lost with ordinary tubes
in this way. My improvement is more especially designed for use in plain tubes
and with or without the ribbed tube-end protectors shown in my Patent No. 21,717
of 1893, but it may be used with ribbed tubes and without the especial formn of
tube-end protectors before referred to.
In carrying out my invention, I take strips or thin bars of any suitable metal,
preferably iron, and twist them so as to cause them to assume a spiral form, and
secure them to holders which are preferably made in the form of the tube protectors
shown in my aforesaid Patent, but they may be made of any other form such as a
simple thimble. I prefer to attach the distributors to the holders by splitting
their ends into three parts, and attaching said ends to the holders, either to the
ends of the ribs if there are any in the holders, or to the inner walls of the holders
or thimbles if there are no ribs on them.
I intend to use my distributors in all styles of boilers or water heaters in which
they may be found applicable, either horizontal or vertical, and in plain or ribbed
tubes; and to assist in keeping them from contact with the walls of the tube, I may
attach cross pieces by rivetting or otherwise.
The holders may be complete cylinders, fitting the tube tightly, or they may be
slightly tapering, or they may be provided with a slit along one side so that they
may be closed in slightly to enable them to enter the tube and then expand by
their own resiliency to tightly fit the tube, and thus hold the same, central."
When the distributors are used in vertical boilers, I prefer to drop them in from
the top, but they may be inserted from the lower end.
Dated this 11th day of September 1894.
W. P. THOMPSON & BOULT,
Agents for the Applicant.
J

page_text: A communication from CHARLES WILLIAM WHITNEY, of 64, 66, and 68 Broadway,
New York City, United States of America, Commission Merchant.
I, ALFRED JULIUS BOULT, of 323 High Holboru, London, in the County of
Middlesex, Patent Agent, 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 :-
The object of this invention is to provide a device for distributing or circulating
the heated gases in tubular boilers, so that instead of their passing through the
tubes in solid bodies, into which they are usually drawn by the action of the draft,
they will be broken up and forced into contact with the walls of the tubes, thereby
more certainly utilizing the heat they contain before it passes out of the tube and
into the smoke-stack, the vast majority of the heat being lost with ordinary tubes
in this way. This improvement is more especially designed for use in plain tubes
and with or without the ribbed tube-end protectors shown in Patent No. 21,717
of 1893, but it may be used with ribbed tubes and without the especial form of
tube-end protectors before referred to.
The accompanying drawing shows various ways of carrying out the invention;
in said drawing-
Figure 1 is a perspective view of a distributor and ribbed protector constructed
according to this improvement and set in an ordinary plain boiler tube which is
represented broken away the better to show the invention.
Figure 2 is a similar view of the same in a ribbed tube, but with a protector
without ribs.
Figures 3, 4, 5, 6 and 7 show different modifications which will be more fully
referred to hereafter.
Referring now to the details of the drawing by letter, and more particularly to
Figures 1 and 2-A represents the boiler tube in both figures, B a holder in the
form of a tube-protector, preferably substantially like that shown in my Patent
No. 21,717 of 1893 before referred to, and as shown in Figure 1, although my
correspondent does not limit himself to this form, as others may be used, such for
instance as those shown in the other figures of the drawing. Attached to this
holder is a spiral distributor C, made of a strip of any suitable metal, which may
be secured to it in any desirable manner, but it is preferred to secure it to the
ribs D as shown. This it is believed is best done by dividing the end of the
distributor into narrow strips E, each strip being rivetted or otherwise secured to
one of the ribs, three of which extend beyond the end of the holder for this purpose,
but some other plan may be adopted.
As shown in Figure 1 of the drawing, the tube is of the plain form, but the
distributor may be used with ribbed tubes as shown in Figure 2, in which case it
may be found convenient to have the ribs of the tube begin at a greater distance
from the end than is usual and the distributor should be narrower. The holder is
shown plain inside, but it may be ribbed as in Figure 1.
It is preferred to make a slit or opening down one side of the holder as shown
at. F, so that there may be sufficient elasticity to allow of its being reduced slightly
in diameter in order to readily enter a tube and then expand again to fit tightly
therein, by which means the tubes will be less likely to leak, as the joint of the
tube with the tube-sheet will be braced and protected from the direct action of
the gases. To prevent the heat distributor from sagging in horizontal boilers and
from swaying in vertical boilers, there may be rivetted on cross pieces G the length
of the internal diameter of the tube, at such spaces as may prove necessary, which

page_text: will keep the heat distributor positively in the centre of the tube, but this is not
always necessary especially in vertical boilers, because the protector will hold the
distributor central in the tube if the tube protector and distributor be properly
made and secured together, and particularly is this so where the distributors are
short.
In Figure 3, a plain tube is shown attached to a plain slit thimble.
Figure 4 shows a protector similar to that in Figure 2, in a plain tube.
In Figure 5 is shown a slit thimble with a slight projecting rim covering the end
of the tube.
In Figures 2, 3, 4 and 5 the ends of the strips E are passed inside the thimbles
or protectors and rivetted thereto, but these thimbles may if preferred be provided
with projections to which said strips may be attached.
The distributors may be very advantageously used in vertical boilers and will
overcome one of the main objections to them, which will cause such boilers to be
used in many places where they are not now used, notwithstanding the favor in
which they are held for many purposes, from the small floor space they occupy, the
fact that the heat is all used on the inside (instead of outside, where part of it is
lost as in the ordinary brick-set horizontal boiler), their lower cost, and their
freedom from clogging of the tubes. The objection to vertical boilers which
prevents their use in many cases, notwithstanding the great demand for them other-
wise, is the enormous loss of heat, owing to the short tubes necessarily used in them
(as otherwise they would be inconveniently high) and the short time the products
of combustion remain in them. This objection will be readily overcome by this
improvement, as the distributors will cause the heated gases to pursue a serpentine
course through the tubes, thus in effect lengthening them, or actually increasing
the time which the gases take to pass through them, and thereby obviating the
disadvantage above alluded to. By securing to the end of the spiral distributor a
means for holding it in the tube, the distributor may be readily dropped into the
top of a vertical tube and held suspended there by the collar of the tube-end
protector, which collar will rest on the top tube sheet and hold the distributor in
the centre of the tube; or it may be inserted from the fire end and held fast by the
expansion of the tube of the holder as before described.
Convenient forms of holders for vertical boilers are shown in Figures 6 and 7,
in which the holders are short tubes having projecting arms united at top and
forming a standard in which is securely suspended a hanger to carry the distributor.
The hanger in Figure 6 is simply a rod having a hook at its lower end which passes
through a hole in the top of the distributor, while the hanger in Figure 7 is
broadened at the bottom, so that the distributor may be rivetted to it.
Where the cross pieces are used in horizontal tubes they should be set
horizontally.
My correspondent is aware that spiral distributors, or more properly speaking,
"retarders," have before been employed, but where they are used with plain tubes
they rest on the bottom and the heat cannot therefore circulate around them; and
thus resting they increase the tendency to fill up this portion of the tubes, which,
even without this, are almost rendered useless as a means of generating steam by
the accumulation of soot and particles of ashes which are carried into the tubes by
the draft and naturally fall to the bottom. This distributor on the contrary does
not touch the inner wall of the tube at any point, but is held firmly in the center
of the tube, so that it admits of the circulation of the gases all around it, opens up
the gaseous currents and forces them against the walls of the tube where they do
some good, instead of allowing them to pass through the tube in a solid stream to
be largely wasted by passing undisturbed into the smoke-stack.
My correspondent does not intend to limit himself to the use of my tube-end
protector in connection with the heat distributor, as any form of protector or
thimble may be used, or any other form of attachment which will hold the
distributor clear of the bottom or walls of the tube. Nor does he limit himself to
any particular length or width of distributor, as it may be found desirable to vary

page_text: these with different lengths and diameters and descriptions of tubes or styles of
boilers.
Having now particularly described and ascertained the nature of the said inven-
tion, as communicated to me by my foreign correspondent and in what manner
the same is to be performed, I declare that what I claim is :
1. A heat distributor for boiler tubes provided with a holder secured thereto at
one end, and constructed to hold it free from the walls of the tube, substantially as
described.
2. In combination with a tabe protector, a heat distributor having one end
divided and attached to said tube protector, substantially as described.
3. As a new article of manufacture; a combined tube protector and heat
distributor constructed 'and arranged substantially as shown and described.
Dated this 4th day of June 1895.
BOULT & WADE,
Agents for the Applicant.