Improvements in Feed Heaters for Steam Boilers.
Year: 1889

page_text: Date of Application, 18th Feb., 1889
Complete Specification Left, 16th Nov., 1889-Accepted, 4th Jan., 1890
PROVISIONAL SPECIFICATION.
Improvements in Feed Heaters for Steam Boilers.
I, HECTOR MAC COLL, of Abercorn House, Sydenham, in the County of Down,
Ireland, Engineer, do hereby declare the nature of this Invention to be as follows, that
is to say:
My said Invention has for its object to apply improved feed-heating apparatus in a
manner to prevent, especially in steam boilers working with the high pressures
recently become common, the injurious action due to differences and changes of
temperature occurring when water is fed into such boilers in a cold or comparatively
cold condition.
In carrying out my Invention I combine a number of cylindrical shells of graduated
sizes with end plates or castings in a manner to form a series of annular cylindrical
spaces. The number of spaces and shells may be varied but I prefer to employ five
or other odd number. By a connection with the feed pipe at the outer end of the
heater the water first enters the central or first space; and on reaching the inner
end proceeds through passages in the inner end casting into the third space. The
water returns towards the outer end through the third space, and then proceeds by
passages in the outer end casting into the fifth or outermost space going through it to
the inner end casting by a passage in which it reaches a delivery pipe. The second
and fourth annular cylindrical spaces are open at their ends; and as the apparatus
is designed to be placed in the steam space of the boiler the steam has free access to
the said second and fourth spaces and also to the outside of the fifth space. The
delivery pipe dips a short distance below the surface of the water in the boiler.
With the apparatus hereinbefore described, if made of suitable size in each case,
the feed water will become heated almost to the temperature of the water in the
boiler before mixing therewith.
Dated this Sixtoonth day of Fahmin 1889
.
EDMUND HUNT,
Applicant's Agent.
+
COMPLETE SPECIFICATION.
Improvements in Feed Heaters for Steam Boilers.
1, HECTOR MAC COLL, of Abercorn House, Sydenham, in the County of Down,
Ireland, 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 said Invention has for its object to apply improved feed-heating apparatus in a
manner to prevent especially in steam boilers working with the high pressures recently
become common,
the injurious action due to differences and changes of temperature
occurring when water is fed into such boilers in a cold or comparatively. cold
condition.
In carrying out my Invention I combine a number of cylindrical shells of graduated
sizes with end plates or castings in a manner to form a series of annular cylindrical
spaces, the number of spaces and shells being varied in different cases according to
conditions and requirements. By a connection with the feed pipe the water enters
one end casting and after passing successively through some of the annular cylindrical
spaces proceeds by a delivery pipe from the other end casting. A. boiler may be
provided with two or more of the feed heaters, as it is sometimes convenient to make
them of comparatively small size to facilitate their introduction into, and arrangement
in a steam boiler; and when there are two or more feed heaters the water is by
-

page_text: preference passed through them successively, the delivery pipe from the last dipping
a short distance below the surface of the water in the boiler.
With my 'improved apparatus, if made of suitable dimensions in each case, the feed
water will become heated almost to the temperature of the water in the boiler before
mixing therewith.
Figures, 1, and 2, on sheet, 1, of the accompanying explanatory drawings are
vertical sections, as at right angles to each other of a steam boiler and show a con-
venient mode of arranging my improved feed-heating apparatus in the steam space
of the boiler. On sheet, 2, of the drawings figures, 3, 4, 5, are enlarged views of
one modification of feed heater, being respectivly an end elevation, a transverse
vertical section and a longitudinal section. Figures, 6, 7, 8, are similar views of a
second modification. In figure, 5, the upper half is a section as at the line A-B,
and the lower half is a section as at the line B-C, in figures, 3, and 4. In these
drawings the same reference numerals are used to mark the same or like parts
wherever they are repeated.
In the feed beater shown in figures 3, 4, and 5, there are five cylindrical shells or
tubes, 11, 12, 13, 14, 15, which may be of any convenient length. These tubes are
of graduated sizes and are placed concentrically one within the other so as to form
four annular cylindrical spaces in addition to the internal space of the innermost
tube, 11. The tubes are held between two end castings, 16, 17, their ends being
fitted into annular grooves in the inner faces of the end castings, and long tie bolts, 18,
being used to fix the end castings and tubes together. The feed pipe is connected
so as to lead the water first through one end casting, 16, into the central space, 19;
and on reaching the other end casting, 17, the water proceeds by passages, 20, formed
therein into the third space, 21. The water returns through this space, 21, to the
end casting, 16, and proceeds by passages, 22, therein into the fifth or outermost
space, 23, from the other end of which it proceeds by a passage, 24, in the end
casting, 17, to a delivery pipe, or to a pipe leading to a second feed heater. The
second and fourth annular cylindrical spaces, 25, 26, communicate by openings, 27,
in the end castings, 16, 17, with the boiler steam space, so that the steam has free
access to the said spaces, 25, 26, as well as to the outside of the outermost shell, 15.
In the modification shown in figures, 6, 7, 8, there are fewer tubes or shells,
namely four, 11, 12, 13, 14, and the passages in the end castings, 16, 17, are made
so that the course of the water is from the centre of one end casting, 17, through
the innermost tube, 11, back. through the annular cylindrical space between the inner-
most and next tubes, 11, 12, to the end casting, 17, next through the annular
cylindrical space between the outermost and next tubes, 14, 13, and finally through
passages in the end casting, 16, to its centre opening. There is only one inner steam
space, namely the annular cylindrical space, 26, between the second and third
tubes, 12, 13.
In figures, 1, and 2, the feed heaters are shown as supported on stay rods, 28,
by means of clips, 29; but they may be carried in any other convenient way.
In any of the modifications the tubes or some of them may be corrugated longi-
tudinally or otherwise to increase the surface.
.
Having now particularly described and ascertained the nature of my said Inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
The improved construction of feed heater for steam boilers in which a number
of cylindrical shells or tubes of graduated sizes are arranged concentrically and
combined with end castings formed with passages to lead the water through some
of the spaces and to give the steam access to other spaces substantially as and for
the purposes herein before described.
Dated this Fifteenth day of November 1889.
EDMUND HUNT,
Applicant's Agent.