IMPROVEMENTS IN STEAM BOILERS
Year: 1876

page_text: LETTERS PATENT to Charles John Galloway, of the Knott Mill Iron Works,
Manchester, in the County of Lancaster, Engineer, for the Invention of
"IMPROVEMENTS IN STEAM BOILERS."
PROVISIONAL SPECIFICATION left by the said Charles John Galloway
at the Office of the Commissioners of Patents on the 14th January 1876.
CHARLES JOHN GALLOWAY, of the Knott Mill Iron Works, Manchester, in the
County of Lancaster, Engineer. "IMPROVEMENTS IN STEAM BOILERS."
My improvements relate more particularly to the construction of steam boilers
now generally known as Calloway" boilers, in which one or more internal flues
either of a circular, elliptical, or other curved form, are provided having tapering
transverse water tubes fixed therein; the said improvements are however equally
applicable to all single or double internal flued or cornish boilers. In such boilers,
when the internal flue or flues are continued of their full diameter to the back plate
of the boiler, the rivets that secure them to the back plate approach at one point
or at two points of the circumference so near to the rivets that secure the back
plate to the cylindrical shell, that no sufficient surface of back plate intervenes
between the two lines of rivetting to allow freedom for expansion and contraction
of the flue without straining the rivets, and in consequence hereof a leakage
frequently occurs at the rivet holes at those points. Now, according to my present
Invention, I obviate this defect by stopping short the cylindrical flue at the point
or points where it approaches nearest the cylindrical shell of the boiler, and con-
necting it to the back plate at such point or points by means of a bent plate of
such a form that it fits the cylindrical or other curved surface of the flue and then
curves inwards away from the cylindrical shell, and is rivetted with a straight or
slightly curved flauge to the back plate at some distance from the shell. The holo
in the back plate for the flue is thus made to present the form of a circle, ellipse,.
or other curve, with a segment or segments cut off at the point or points where it
approaches nearest the cylindrical shell. By this arrangement sufficient surface is
provided in the back plate to allow freedom of expansion and contraction for the
lue without straining the rivets, in addition to which the curved form of the
Price d
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page_text: connecting plate or plates also allows it or them to yield somewhat as the flue
expands or contracts, so that the whole strain is not put upon the back plate.
According to another arrangement, stop the entire circular or other shaped
flue short of the back plate, and I connect the two parts by means of a solid welded
iron ring that fits the flue at one end and then curves inwards all round, so
as to fit with a flange against a hole of sufficiently reduced size in the back
plate.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed by
the said Charles John Galloway in the Great Seal Patent Office on the 7th
July 1876.
CHARLES JOHN GALLOWAY, of Knott Mill Iron Works, Manchester, in the County
of Lancaster, Engineer. "IMPROVEMENTS IN STEAM BOILERS."
"
My improvements relate more particularly to the construction of steam boilers
now generally known as Galloway" boilers, in which one or more internal flues
either of a circular, elliptical, or other curved form are provided, having tapering
transverse water tubes fixed therein; the said improvements are however equally
applicable to all single or double internal flued or cornish boilers. In such boilers
when the internal flue or flues are continued of their full diameter to the back plate
of the boiler, the rivets that secure them to the back plate approach at one point
or at two points of the circumference so near to the rivets that secure the back
plate to the cylindrical shell, that no sufficient surface of back plate intervenes
between the two lines of rivetting to allow freedom for expansion and contraction
of the flue without straining the rivets, and in consequence thereof a leakage
frequently occurs at the rivet holes at those joints. Now, according to my present
Invention, I obviate this defect by stopping short the flue at the point or points
where it approaches nearest the cylindrical shell of the boiler, and connecting it
to the back plate at such point or points by means of a bent plate of such a form
that it fits the cylindrical or other curved surface of the flue, and then curves
inwards away from the cylindrical shell, and is rivetted with a straight or slightly
curved flange to the back plate at some distance from the shell.. The hole in the
back plate for the flue is thus made to present the form of a circle, ellipse, or other
curve, with a segment or segments cut off at the point or points where it approaches
nearest the cylindrical shell. By this arrangement sufficient surface is provided in
the back plate to allow freedom of expansion and contraction for the flue without
straining the rivets, in addition to which the curved form of the connecting plate
or plates also allows it or them to yield somewhat as the flue expands or contracts,
so that the whole strain is not put upon the back plate.
According to another arrangement I stop the entire circular or other shaped fluo
short of the back plate, and I. connect the two parts by means of a solid welded
iron ring that fits the flue at one end and then curves inwards all round, so as to
fit with a flange against a hole of sufficiently reduced size in the back plate.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 represents a transverse section; and Fig. 2, a sectional plan of a boiler,
having two cylindrical flues to which my Invention is applied; and Fig. 3 represents
a transverse section; and Fig. 4, a sectional plan shewing its application to a boiler,
having a flue of the kind described in the Specification to Letters Patent granted
to me, the said C. J. Galloway and C. H. Holt, on the 13th July 1875, No. 2514.
Referring to Figs. 1 and 2 it will be scen that the ends of the flues at the sides
next the outer casing are connected to the end plate of the boiler by curved portions
bent inwards, which may either be made in one piece with the body of the fluc as
shewn at A, or may be a separate piece as shown at B. In Figs. 3 and 4 a like

page_text: construction is shown, the bent-in portion of the flue being either in one piece with
it, as at C, or being a separate piece, as at D. It is obvious that a bent piece,
such as B or D, instead of extending partially round the flue might be carried
entirely round it.
Having thus described the nature of my Invention and in what manner the
same is to be performed, I claim connecting the ends of internal flues of boilers to
the end plates thereof by curved portions bent inwards to allow for expansion or
contraction, substantially as herein described.
In witness whereof, I, the said Charles John Galloway, have hereunto set my
hand and seal, this Sixth day of July, in the year of our Lord One thousand
eight hundred and seventy-six.
CHARLES J. GALLOWAY. (L.S.)