Improvements in Interchangeable Boiler Flues.
Year: 1892

page_text: Date of Application, 8th Oct., 1892
Complete Specification Left, 2nd Nov., 1892-Accepted. 3rd Dec.. 1892
PROVISIONAL SPECIFICATION.
Improvements in Interchangeable Boiler Flues.
I, JAMES ALEXANDER LADE Glenburn Villa Port-Glasgow Scotland Engine
Works Manager do hereby declare the nature of this invention to be as follows:-
The object of this invention is to facilitate the removal and replacing of boiler
flues which are flanged up to meet the back tubeplates, particularly those in marine
boilers, where great difficulty in doing so is at present experienced. In carrying
out my invention the frontplate of the boiler is flanged around the flue opening, the
flue at this end being left plain, and riveted to the inside of flange on frontplate;
the back end of flue on the upper side is flanged up to meet the back tube plate.
On the lower side the back end of flue is cut away at right angles to, and from
some distance above the axis of the flue, sufficiently far to allow of the lower cut
away part coming out clear of the boiler frontplate at the same time that the
upper flanged part comes into contact with the flange on boiler frontplate.
advisedly cut the lower part of flue away at right angles to its axis, as by that
means when the flue has been drawn out through the frontplate until the cut away
part is clear thereof; it can then be lowered bodily until the upper flanged part
clears frontplate, and then drawn out completely clear.
Dated this 3rd day of October 1892.
JAMES ALEXANDER LADE.
COMPLETE SPECIFICATION.
Improvements in Interchangeable Boiler Flues.
JAMES ALEXANDER LADE Glenburn Villa Port-Glasgow Scotland Engine
Works Manager 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 object of this invention is to facilitate the removal and replacing of boiler
flues which are flanged up to meet the back tubeplate, particularly those in marine
boilers where great difficulty in doing so is at present experienced.
In carrying out my invention the frontplate of the boiler is flanged around
the flue opening, the flue at this end being left plain and riveted to the inside of
flange on frontplate: the back end of flue on the upper side is flanged up to meet
the back tubeplate.
On the lower side the back end of flue is cut away at right angles to, and pre-
ferably from some distance above the axis of the flue, sufficiently far back from
flanged portion to allow of the lower cut away part coming out clear of the boiler
frontplate at the same time that the upper flanged part comes into contact with the
flange on boiler frontplate.
I advisedly cut the lower part of flue away at right angles to its axis, as by that
means when the flue has been drawn out through the frontplate until the cut away
part is clear thereof, it can then be lowered bodily until the upper flanged part
clears the frontplate, then drawn out completely clear.
The accompanying drawings shew-in Fig. 1, a longitudinal section of the flue
in position, and in Fig. 2 a similar view of the flanged end of flue in course of
removal.
A is the flue which may be made of any ordinary construction, (either ribbed,
suspension, corrugated, barrel shaped, or plain) having the front end terminating in
a plain cylindrical portion B, and its other end flanged at C for a part of its

page_text: circumference. The extent of the flanged part C depending upon the shape of the
combustion chamber, but in most cases it would be made of such a size as just to
pass through the opening in frontplate F.
In the drawings the flange C is shewn stopped about the point C₁, the exact
position depending as stated before upon the shape of the combustion chamber.
The lower portion of the back end of flue from D to E is cut away at right
angles to its axis some distance from the flanged portion C, so that when the flue is
partly withdrawn as shewn in Fig. 2 with the cut away part clear of frontplate
it may then be lowered bodily until the flange on top of flue clears flange on
frontplate, then drawn out completely clear.
By this means it will be seen that an existing boiler flue may be easily removed
and replaced either by a new one, or after having been repaired, without otherwise
disturbing the boiler."
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 :-
A boiler flue having no flange at one end and partly flanged as at C, and partly
cut away at right angles to its axis as at D. E. at its other end, for the purpose
of removal and replacement substantially as described and illustrated in the
accompanying drawings.
Dated this 31st day of October 1892.
JAMES A. LADE.