Strengthening Metallic Rings and Tubes, Specially Applicable to Boiler Flues or Fire-boxes.
Year: 1885

page_text: Strengthening Metallic Rings and Tubes, Specially Applicable
to Boiler Flues or Fire-boxes.
E
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HOMAN PRICE FENBY of 13 Westfield Place, Leeds in the County of York,
Engineer do hereby declare the nature of my invention for STRENGTHENING
METALLIC RINGS AND TUBES, SPECIALLY APPLICABLE TO -BOILER FLUES OR FIRE
BOXES, to be as follows:-
'
נה ני
1
06 ...
My Invention relates chiefly to Improvements in the construction of boiler flues
or fire-boxes.
+1
Instead of forming a number of undulations, or corrugations round the tube or
fire-box in an annular direction and at right-angles with the tube or flue axis, as
is now the practice, I form a number of flutes or alternate, ridges and hollows
running round the the tube or fire-box askew, preferably at an angle of about
forty-five degrees, thus giving the tube great longitudinal strength as well as
rigidity to resist collapse, and so providing a valuable stay, for the boiler ends.
Davon uns 2180 day of October FOOD,
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HOMAN PRICE FENBY..
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page_text: t
Strengthening Metallic Rings and Tubes, Specially Applicable
to Boiler Flues or Fire-boxes.
I, HOMAN PRICE FENBY, of 13 Westfield Place, Leeds in the County of York,
Engineer, do hereby declare the nature of my invention for STRENGTHENING
METALLIC RINGS AND TUBES, SPECIALLY APPLICABLE TO BOILER FLUES OR FIRE-
BOXES 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 tubular flues and fire-boxes for boilers and has for its
object to obtain the maximum of strength both transversely and longitudinally
in the said flues and fire-boxes.
According to my Invention I form a number of flutes or alternate ridges and
hollows constituting corrugations running round or partly round the tubular flue
or' fire-box at a quick pitch' such as will 'combine the advantages of the greatest
attainable transverse and longitudinal strengths giving the great rigidity to resist
transverse collapse and great strength against longitudinal collapse and will con-
stitute a valuable stay for the ends of the boiler.
I am aware that tubular flues and fire-boxes have been made with corrugations
which run there around in planes at right angles to the axis of the flue or box,
but although this gives strength against transverse collapse it greatly weakens
the flue or box as far as longitudinal strains and thrusts are concerned.
I am
further aware that it has been proposed to make the tubes and boxes with a
corrugation running there around after the manner of a single screw thread or
helix but this does not obviate the weakening of the flue or box longitudinally.
By my Invention I attain the hereinbefore mentioned object of transverse and
Hongitudinal strength combined by disposing the corrugations so as to form a rapid
or multiple thread or a number of helices so as to gain great strength against
longitudinal strains and thrusts combined with the necessary strength to resist
transverse collapse. I find that a twist of the corrugations presenting an angle
of about forty-five degrees to the axis of the flue or box gives the best results,
although I do not limit myself to this particular angle provided that it is an angle
such as will attain sufficiently the combined longitudinal and transverse strengths,
which is the object of my Invention.
I expressly exclude from my claim corrugations which are either in the form of
rings concentric to the axis of the flue or box or are disposed as a simple belix or
single screw thread. The accompanying drawing shews a flue provided with what
I consider the best form of my Invention. The several distinct rapid helical
corrugations are marked with the numerals 1 to 15. It will be understood that
the number of the corrugations will vary with their size and the size of the flue
or box to which they are applied.

page_text: Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is:-
The manufacture and use of tubular flues or fire-boxes with corrugations in
the form and disposition of a number of helices after the manner of a multiple
threaded screw the corrugations being of such a pitch or twist as to offer the
greatest resistance against collapse combined with great lateral strength substan-
tially as and for the purpose set forth and described and also as illustrated by the
accompanying drawing.