An Improvement in Galloway Boilers.
Year: 1892

page_text: Date of Application, 24th Dec., 1892
Complete Specification Left, 21st Sept., 1893-Accepted, 21st Oct., 1893
PROVISIONAL SPECIFICATION.
An Improvement in Galloway Boilers.
I, CHARLES JOHN GALLOWAY, of Knott Mill Iron Works, Manchester in the
County of Lancaster, Engineer, do hereby declare the nature of this invention to
be as follows:-
The tube of a Galloway boiler, as is well known, is tapered from its lower end to
a larger diameter at its upper end, and both its ends are flanged to be secured to
the plates of the flue which the tube crosses. Owing to the taper form of the tubes
there are larger spaces of the flue plates unsupported between their lower ends
than between their upper ends, and consequently the flanges at the lower ends have
to sustain greater pressure than the flanges at the upper ends. Moreover, the
lower flange has to be worked out of the smaller end of the tube where there is
less metal disposable for its formation and consequently the flange is thinner.
My invention relates to means of providing increased strength at the small end
of the tube and its flange, which I effect by rolling the plate out of which the
taper tube is to be formed, with greater thickness at that side of the plate which is
to form the small end of the tube than at the other edge which is to form the larger
end of the tube, so that, when the flange is worked out of it, there is sufficient
metal available to give the required strength.
Dated this 24th day of December 1892,
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improvement in Galloway Boilers.
I, CHARLES JOHN GALLOWAY, of Knott Mill Iron Works, Manchester, in the
County of Lancaster, 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 :-
The tube of a Galloway boiler, as is well known, is tapered from its lower end
to a larger diameter at its upper end, and both its ends are flanged to be secured
to the plates of the flue which the tube crosses. Owing to the taper form of the
tubes there are larger spaces of the flue plates unsupported between their lower
ends than between their upper ends, and consequently the flanges at the lower ends
have to sustain greater pressure than the flanges at the upper ends.
Moreover, the lower Hange has to be worked out of the smaller end of the tube
where there is less metal disposable for its formation, and consequently the flange is
thinner.
My invention relates to means of providing increased strength at the small end
of the tube and its flange, which I effect by rolling the plate out of which the
taper tube is to be formed, with greater thickness at that side of the plate which is
to form the small end of the tube than at the other edge which is to form the larger
end of the tube, so that when the flange is worked out of it, there is sufficient
metal available to give the required strength.
Fig. 1 of the accompanying drawings is an elevation, and Fig. 2 is a section of
a plate adapted to form a Galloway tube of section shewn by Fig. 3.
The plate
is rolled so as to have greatest thickness at its lower or narrow end L and its least
thickness at its upper or broad end U, the thickness decreasing gradually
from L to U. Thus the tube formed by bending the plate round, welding its
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page_text: edges, and forming flanges at its ends, is of thicker metal, and consequently of
greater strength in its lower part than in its upper part, and is therefore more
capable of sustaining the pressure on the larger unsupported area of boiler plate
where its lower end is attached.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
A Galloway boiler tube having its lower small end and flange of thicker metal
than its upper large end, substantially as and for the purpose set forth.
Dated this 21st day of September 1893,
ABEL & IMRAY,
Agents for the Applicant.