Improvements in Water-tube Steam Generators.
Year: 1893

page_text: Date of Application, 23rd Jan., 1893
Complete Specification Left, 7th June, 1893-Accepted, 16th Dec., 1893
PROVISIONAL SPECIFICATION.
[Communicated from abroad by MONTAGUE HERBERT CHURCHILL SHANN, of
Preston, in the Colony of Victoria, Australia, Engineer.]
Improvements in Water-tube Steam Generators.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
45 Southampton Buildings, in the County of Middlesex, do hereby declare the
nature of this invention to be as follows:-
My invention relates to improvements in water-tube steam generators.
The principal object of my invention is to construct a cheap and efficient water-
tube boiler in which a good circulation is insured and in which improved means are
employed for heating the feed water, and for the prevention of priming.
It has hitherto been the practice to employ inclined straight tubes in water-tube
boilers, and to supply the feed-water to a receptacle connected with the lower
ends of the said tubes, the currents of steam being drawn from the upper ends of
the same.
According to my invention I provide my said improved boiler with a series of
rows of parallel inclined tubes, enclosed in a suitable casing, above a fire-grate.
Each tube is bent into U shape, or a pair of tubes are connected in any suitable
manner to form a member consisting of parallel straight portions connected by a
junction-piece or a bend; each said member is so placed in the boiler that the
straight portions are both inclined, and the bend or junction-piece connects the
parts of each which are at the lower level. The upper leg or portion of each
member is connected with a header communicating with a drum or other receptacle
into which the feed is delivered, and the lower leg or portion is in connection with
another header connected with the said drum.
The said lower legs being nearer the fire than the upper legs, the generation of
steam in the former is more rapid than in the latter, and consequently a current is
set up in the said lower leg sufficient to cause a flow of water down the upper leg to
the lower end of the lower leg, whence it ascends in the usual manner.
The arrange-
ment of the said members to secure a flow of water in the manner described is an
important feature of my invention.
I prefer to employ more than one tier of the said tubular members, and to
arrange them so that the flames and hot gases from the fire pass into contact with
more than one tier of lower legs of the said members, before they reach any of the
upper legs, so that the difference of temperature between the upper and lower legs
of each member is made as great as possible, and the rate of circulation thus
increased.
In order to heat the feed-water, I place a small tubular heater in the uptake or
flue, and I cause the whole or a part of the products of combustion to pass through
the tubes thereof, to heat the feed-water which is passed through the said
tubular heater to the steam-drum from the lower portion of which it is drawn
through the headers which communicate with the upper legs of the tubular members
as aforesaid.
Steam is withdrawn from the steam drum by a pipe, which is perforated along
one side only. A plate is secured to the interior of the steam drum and bent so as
to screen the pipe except on the side on which it is not perforated. The said bent
plate acts as a baffle to prevent the passage of priming water into the steam pipe.
Moreover the pipes leading into the steam drum from the headers in which the
steam ascends, are fitted with curved ends which deflect the ascending streams
towards the back of the aforesaid baffle as they enter the drum, and away from
the passage by which steam passes the baffle on its way to the steam pipe. A

page_text: pipe passes from the upper portion of the said small tubular heater into the steam
drum at a point behind the. aforesaid baffle, and delivers the hot feed thereinto.
Suitable deflectors are provided to direct, the products of combustion in the
proper course, and mud drums, manholes, and other fittings are provided as is
customary.
Dated this 23rd day of January 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
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COMPLETE SPECIFICATION.
Improvements in Water-tube Steam Generators.
I, HENRY HARRIS LAKE of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 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 :-
My invention relates to improvements in water tube steam generators..
The principal object of my invention is to construct a cheap and efficient water
tube boiler in which a good circulation is ensured.
It has hitherto been the practice to employ inclined straight tubes in water tube
boilers and to supply the feed water to a receptacle connected with the lower ends
of said tubes, the current of steam being drawn from the upper ends of same.
According to my invention I provide my said improved boiler with a series. or
rows of parallel inclined tubes, enclosed in a suitable casing above a fire grate.
Each tube is bent into U shape, or a pair of tubes are connected in any suitable
: manner to form a member consisting of parallel straight portions connected by a
junction piece or a bend; each said member is so placed in the boiler that the
straight portions are both inclined and the hand or junction piece connects the parts
of each which are at the lower bend.
:
The upper leg or portion of each member is connected with a header com-
municating with a drum or other receptacle into which the feed is delivered, and
the lower leg or portion is in connection with another header connected with. said
drum from which the steam is withdrawn for use. The said lower legs being nearer
the fire than the upper legs the generation of steam in the former is more rapid
than in the latter and consequently a current is set up in the lower leg sufficient to
cause a flow of water down the upper leg to the lower end of the lower leg whence
it ascends in the usual manner. The arrangement of the said members to secure.a
flow of water in the manner described is an important feature of my invention.
I prefer to employ more than one tier of the said tubular members. and to
arrange them so that the flames and hot gases from the fire passi into contact with
more than one tier of lower legs before they reach any of the upper legs, so that
the difference of temperature between the upper and lower legs of each member is
made as great as possible and the rate of circulation thus. increased.
The feed is drawn into the header or headers which communicate with the upper
legs of the tubular members aforesaid.
Mud drums, manholes, hand holes and other fittings are provided as.is.customary.
In order that my said invention may be better understood. I will now refer to
the accompanying drawings in which the same letters of reference: indicate
corresponding parts in all the figures.
Figure 1 is a diagrammatic sectional elevation of the boiler.
Fi
Figure 2 is a similar view showing a modified arrangement of. the headers.
Figure 3 is a further modified arrangement of the.headers.
Figure 4 is a front elevation of Figure 2 and
Figure 5 is a front elevation of Figure 3.

page_text: A A form the upper legs and B B the lower legs of two tubular members
respectively.
M is the junction piece at the lower ends of the said legs which may be common
to two or more tubular members.
F is the header or chamber with which the upper legs A A communicate and
G the header with which the lower legs B B communicate. In Figure 1 I have
shown a diaphragm C which is arranged to form the two chambers or headers F
and G, the said diaphragm being provided with a passage I and holes L as shown.
Jis the steam drum communicating by means of a suitable pipe with the
headers F and G, and M is the bend or junction piece for connecting the lower
ends of the tubes or legs A and B so as to allow of the circulation of the water
through the same :
In this first arrangement of the headers F and G they lie one in front of the
other.
In Figure 2 the diaphragm dividing the chamber F from the chamber G is
arranged horizontally.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is :-
1. The combination with two headers or chambers (F) and (G) arranged one in
front of the other, of the upper and lower legs (A), (A) and (B), (B) of a series
of inclined straight tubes of a water tube steam boiler, substantially as hereinbefore
described and as illustrated in the drawings.
2. The combination with two headers or chambers (F) and (G) arranged one on
top of the other, of the upper and lower legs (A), (A) and (B) (B), of a series of
inclined straight tubes of a water tube steam boiler substantially as hereinbefore
described and as illustrated in the drawings.
3. The combination with two headers or chambers arranged side by side, of the
upper and lower legs (A) (A) and (B) (B) of a series of inclined straight tubes of
a water tube steam boiler substantially as herein before described and as illustrated
in the drawings.
Dated thia 7th day of June 1802
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.