An Improvement in Tubular Boilers.
Year: 1889

page_text: Date of Application, 9th Nov., 1889
Complete Specification Left. 9th Aug., 1890-Accepted, 13th Sept., 1890
PROVISIONAL SPECIFICATION.
An Improvement in Tubular Boilers.
I, ALFRED FERNANDEZ YARROW, of Isle of Dogs. Poplar in the County of
Middlesex, Engineer do hereby declare the nature of this invention to be as
follows:-
In many tubular boilers particularly those which are worked at very high pressure
with forced draught, it is found very difficult to maintain the tightness of the jointings
of the tubes to the tube plates. My invention relates to means of remedying this
defect in existing boilers without having to remove the tube plates. For this purpose
I employ smaller tubes so as to give more freedom for the circulation of water
between them and for escape of steam from between them, and thus to avoid the
overheating of the tubes which often results from steam being imprisoned between
them. In order to fix these reduced tubes in the existing tube plates which have
holes suited to the larger tubes, I make the small tubes with both their ends made
larger or enlarged by ferrules to the size necessary to fit the holes in the tube plates,
and I screw or expand or both screw and expand these enlarged ends in the holes.
Or, instead of making tubes with their ends enlarged, I bush the holes in the tube
plates with ferrules preferably of copper expanding or otherwise securing these
ferrules in the holes, then I introduce the smaller tubes and expand or otherwise
secure them in the ferrules.
Dated this 6th day of November 1889.
ABEL & IMRAY.
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improvement in Tubular Boilers.
1, ALFRED FERNANDEZ YARROW of Isle of Dogs, Poplar in the County of
Middlesex, 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 :-
In many tubular boilers particularly those which are worked at very high pressure
with forced draught, it is found very difficult to maintain the tightness of the
jointings of the tubes to the tube plates. My invention relates to means of remedying
this defect in existing boilers without having to remove the tube plates. For this
purpose employ smaller tubes so as to give more freedom for the circulation of
water between them and for escape of steam from between them, and thus to avoid
the overheating of the tubes which often results from steam being imprisoned
between them. In order to fix these reduced tubes in the existing tube plates which
have holes suited to the larger tubes, I make the small tubes with both their ends
made larger or enlarged to the size necessary to fit the holes in the tube plates as
shewn at Fig. 1 of the accompanying drawings and I screw or expand or both screw and
expand these enlarged ends in the holes. Or, instead of making tubes with their ends
enlarged, bush the holes in the tube plates with ferrules preferably of copper
expanding or otherwise securing these ferrules in the holes, then I introduce the
smaller tubes and expand or otherwise secure them in the ferrules as shewn at
Fig. 2.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the saine is to be performed I decinre that what I
claim is.
Adapting tubes of reduced diameter to the tube plates of existing boilers having

page_text: holes for larger sized tubes by either enlarging the ends of the tubes so as to fit the
said holes, or by bushing the holes with ferrules having an internal diameter
corresponding to the external diameter of the said tubes, substantially as described.
Dated this 7th day of August 1800
ABEL & IMRAY,
Agents for the Applicant.