Improvements applicable to Water-tube Steam Boilers for Preventing and for Removing Deposits on the Tubes.
Year: 1898

page_text: Date of Application, 1st June, 1898
Complete Specification Left, 28th Feb., 1899-Accepted, 1st Apr., 1899
PROVISIONAL SPECIFICATION.
Improvements applicable to Water-tube Steam Boilers for Preventing
and for Removing Deposits on the Tubes.
I, JAMES WEIR, of Holm Foundry, Cathcart, in the County of Renfrew, North
Britain, Engineer, do hereby declare the nature of this invention to be as follows,
that is to say:-
My invention has for its purpose to facilitate the complete burning of the
hydrocarbon gases from the fuel in water-tube boilers furnished with a mixing
or combustion chamber, such as is shewn and described in my Patent Specifica-
tion No. 28961 of 1896 so as to prevent the emission of smoke and the formation
of scale on the exterior of the tubes, and further, to provide a means whereby the
loose deposit of soot, which may gather while the fires are damped or lighting up,
may be instantly removed.
In water-tube boilers generally a large proportion of the hydrocarbon gases
passes away in the form of thick smoke, even although these boilers be supplied
with a combustion chamber, as it is difficult to ascertain when the requisite amount
of air for proper combustion is being admitted. The smoke passing amongst the
tubes covers them with a tarry scale, particularly when bituminous coal is used,
and this affects, detrimentally, their efficiency as heat conductors. By my inven
tion, the stoker is enabled to see if the fire gases are igniting properly in the com-
bustion chamber, and if not, means are provided by which the requisite amount of
air to produce proper combustion can be admitted for any rate of steaming or
class of coal. According to the color of the flame in the combustion chamber
more or less air is admitted until complete combustion is seen to be attained, and
thus, as the inflammable gases are properly mixed and ignited in the combustion
chamber, any smoke is entirely consumed and the gases pass over the tubes with-
out leaving any 'deposit.
According to one modification, my invention is effected by providing a clear
opening between the heating tubes, through which the gases in the combustion
chamber may be viewed through an aperture in the casing, and in conjunction
therewith, air admission doors capable of adjustment by the stoker. An aperture
is arranged over each furnace door opposite the space between the tubes in a
direct line with the combustion chamber, and is furnished with a transparent eye-
piece to prevent the admission of air. The air admission doors are arranged with
handles by means of which the opening can be adjusted to admit the requisite
amount of air to produce proper combustion, and this amount is ascertained by
observing the color of the flame in the combustion chamber through the aperture
described.
When the fires of the boiler are first lighted up, before the fuel has properly
taken fire it is scarcely possible to avoid producing smoke, and this is also the case
where the fires are damped down for any purpose. Soot naturally collects on the
tubes under these circumstances, but it is not of a scaly nature but simply in the
form of a loose powder, and as such, may be blown off the tubes. For the purpose

page_text: of effecting this I provide a steam connection to a pipe leading across the front
of the heating tubes, having small holes at intervals opposite each space between
the tubes, and a valve or cock which can be closed rapidly, for admitting steam
to the arrangement. I am aware that for experimental purposes sight holes for
the observation of fire gases have already been used with various objects, but
for the purpose of my invention these sight holes are to be used in conjunction
with the air admission apparatus, as a practical factor in the efficient working of
the boiler. I am also aware that steam jets have been previously used in various
ways for clearing the deposit from heating tubes, but none of these are
arranged to effect the blowing off of the soot in the same efficient and simple
manner as that here described.
Dated this Thirty first dose of Mo 1808
EDMUND HUNT,
Applicant's Agent.
Improvements applicable to Water-tube Steam Boilers for Preventing
and for Removing Deposits on the Tubes.
I, JAMES WEIR, of Holm Foundry, Cathcart, in the County of Renfrew, North
Britain, Engineer, 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, that is to say:-
My invention has for its object to facilitate the complete burning of the
hydrocarbon gases from the fuel in water-tube boilers furnished with a mixing
or combustion chamber, such as is shown and described in my Patent Specifica-
tion No. 28961 of 1896 so as to prevent the emission of smoke and the formation
of scale on the exterior of the tubes, and further, to provide a means whereby the
loose deposit of soot, which may gather while the fires are damped or lighting up,
may be instantly removed.
In water-tube boilers generally a large proportion of the hydrocarbon gases
passes away in the form of thick smoke, even although these boilers are supplied
with a combustion chamber, as it is difficult to ascertain when the requisite amount
of air for proper combustion is being admitted. The smoke passing amongst the
tubes covers them with a tarry scale, particularly when bituminous coal is used,
and this affects, detrimentally their efficiency as heat conductors. By my inven-
tion the stoker is enabled to see if the fire gases are igniting properly in the com-
bustion chamber, and if not, means are provided by which the requisite amount of
air to produce proper combustion can be admitted for any rate of steaming or
class of coal. According to the color of the flame in the combustion chamber
more or less air is admitted until complete combustion is seen to be attained, and
thus, as the inflammable gases are properly mixed and ignited in the combustion
chamber, any smoke is entirely consumed and the gases pass over the tubes with-
out leaving any deposit.
And in order that my said invention and the manner of performing the same
may be properly understood I hereunto append a sheet of explanatory drawings
to be hereinafter referred to in describing my improvements.
Figure 1, of the accompanying drawings is a sectional side elevation of a water-
tube boiler, similar to that described in my Patent Specification No. 28961 of 1896,
provided with my improvements. Figure 2, is an enlarged section of a detail
in connection therewith, and also showing the arrangement of the heating tubes.

page_text: In these drawings the same reference letters are used to mark the same or like
parts wherever they are repeated.
In carrying out my invention according to one modification the transverse
arrangement of the tubes, A, is as shown in Figure, 2, clear openings being pro-
vided between them thus enabling the gases in the combustion chamber, B, to be
clearly viewed by the stoker through an aperture, C, formed in the smoke-box or
casing door, D. An aperture is arranged over each furnace door, E, directly
opposite a clear space between the tubes, A, in a direct line with the combustion
chamber, B, each aperture, C, being furnished with a transparent eye-piece, F,
to prevent the admission of air. Admission doors, G, are provided for admitting
air to the gases before they enter the combustion chambers, B, and by means of
handled rods, H, and levers, J, they can be conveniently adjusted by the stoker.
With this arrangement the opening can be readily adjusted so as to admit the
requisite amount of air to produce proper combustion, this amount being ascer-
tained by observing the color of the flame in the combustion chamber, B, through
the eye pieces, F.
When the fires of the boiler are first lighted up, before the fuel has properly
taken fire, it is scarcely possible to avoid producing smoke, and this is also the
case when the fires are damped down for any purpose. Soot naturally collects on
the tubes under these circumstances, but it is not of a scaly nature, but simply
in the form of a loose powder, and as such, may be blown off the tubes. For the
purpose of effecting this a pipe, K, is led across the front of the heating tubes, A,
having small holes, L, formed at intervals opposite each space between the tubes, A,
as shown in Figure 2. The perforated pipe, K, is connected to a steam supply
pipe, M, a valve or cock, N, which can be opened and closed rapidly serving to
clear the tubes instantaneously. The steam issuing from the perforations, L,
in the pipe, K, thus forms a series of powerful steam jets, which clear the tubes, A,
effectively from all sooty matter. I am aware that for experimental purposes sight
holes for the observation of fire gases have already been used with various objects,
but for the purposes of my invention these sight holes are to be used in conjunction
with the air admission apparatus, herein before described, as a practical factor in
the efficient working of the boiler I am also aware that steam jets have been pre-
viously used in various ways for cleaning the deposit from heating tubes, but
none of these are arranged to effect the instantaneous blowing off of the soot in
the same efficient and simple manner as that now here described.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed declare that what
I claim is:-
1. In water-tube steam boilers improved means for preventing scaly deposits
on the tubes, consisting in providing sight holes placed over the furnace doors
for inspecting the process of combustion in the combustion chamber, and used
in conjunction with adjustable air admission doors, arranged and operated sub-
stantially as hereinbefore described with reference to the accompanying drawings.
2. In water-tube steam boilers improved means for instantaneously removing
loose deposit on the tubes by means of a fixed perforated steam pipe placed below
the tubes and arranged with a steam connection and valve capable of being
operated rapidly, to direct steam jets up, along, and between the rows of tubes,
substantially as hereinbefore described with reference to the accompanying
drawings.
Dated this Twenty-seventh day of February 1800.