An Improved Ferrule for Steam Boiler Tubes.
Year: 1893

page_text: Date of Application, 13th Jan., 1893
Complete Specification Left, 28th Feb., 1893-Accepted, 1st Apr., 1893
PROVISIONAL SPECIFICATION.
An Improved Ferrule for Steam Boiler Tubes.
I, DAVID JOHN MORGAN, of. Romily House, Romily Road, Cardiff in the
County of Glamorgan, Engineer, do hereby declare the nature of this invention to
be as follows:-
The object of this invention is to provide a better means of protecting the
ends of the tubes in steam boilers, and is more particularly adapted to steam
boilers, where forced draft is employed.
The invention consists in an improvement in the shape of the ferrule. That
part which is inserted in the tube is made of considerable length, so as to protect
the latter as much as possible from the fierce action of the flame as well as from
that of the in-rush of cold air.
The periphery of the ferrule is corrugated in such a way that the tops of the
corrugations shall fit easily in the inside of the tube. The shape of these corru-
gations may be varied and can either run around circumferentially or spirally, so
that the ferrule upon cooling will shorten in length and therefore will have a
tendency to tighten up the internal diameter of the tube.-..
The outer portion of the ferrule is flanged over trumpet-shaped, the largest
diameter resting against the tube plate, thus perfectly protecting the end of
the tube.
I propose to add, if necessary, another ferrule, driven tightly into the corru-
gated one, so as to protect the corrugations; the outer end of the said additional
ferrule being bell-mouthed.
On the outside of the corrugations, I propose to apply a coating of any suitable
non-conducting material which will occupy the whole of the space between the
ferrule and the tube. Non-conducting material may also be applied between the
protecting ferrule and the corrugated ferrule, so as to fill up all the space between
the two.
The ferrules may be made of any suitable metal.
Doted this 19th day of Tonuo 1902
PHILLIPS & LEIGH,
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improved Ferrule for Steam Boiler Tubes.
I, DAVID JOHN MORGAN, of Romily House, Romily Road, Cardiff, in the
County of Glamorgan, 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 object of this invention is to provide improved means for protecting the
ends of the tubes in steam boilers, and the invention itself is adapted for use more
especially in steam boilers in connection with which forced draught is employed.
In order that the invention and the means by which it is to be carried into
practical effect may be thoroughly understood, I will now describe it in detail
referring in so doing to the accompanying drawing which is to be taken as part of
this Specification and read therewith.
Fig. 1 is a longitudinal vertical section through the end of a tube, the
principal ferrule, the second ferrule and the adjacent portion of the tube plate.
LD 077

page_text: Fig. 2 is a longitudinal vertical section through the end of the tube, the principal
ferrule and the adjacent portion of the tube plate.
Fig. 3 is a side elevation of a principal ferrule corrugated spirally.
Fig. 4 is a front elevation of a principal ferrule applied to a Serve tube.
A is the boiler tube, and a is one of the ends of it which my invention is adapted
to protect and tighten. B is the adjacent portion of the boiler plate.
C is the principal ferrule. It constitutes the main portion of the invention and
in it is embodied the principal feature thereof.
This feature is the series of corrugations or ribs.
That portion of the ferrule which enters the boiler tube A, is much longer than
it has been the custom to make it. The object in so making it longer is to protect
the tube as much as possible from the fierce action of the flame as well as from
the influence of inrushes of cold air. c', care corrugations. They may be either
parallel with each other as illustrated in Figures 1 and 2, or they may be spiral as
illustrated in Figure 3. I do not confine myself in respect of the size of the
corrugations or of their contour in cross section or of making them or it of the
same or of an equal size or radius.
The function of the corrugations is to provide for the radial expansion of
the ferrule as it contracts longitudinally, so that as it cools it shall expand the tube
and and so tighten it up against the tube plate; and so long as there is corrugation
enough to provide, for the above described expansion, the number shape and
direction of the corrugation or corrugations is immaterial. Any arrangement of
them under the conditions specified is within the scope of my invention.
For the corrugations there may be substituted annular or spiral ribs upon the
external face of the ferrule.
The corrugations as well as the substituted ribs also provide spaces to be utilised
in the manner described further on.
. The front or the outer end of the ferrule C is swaged outwards and backwards
só as to form an annular grooved guard which shall be adapted, in respect of
both diameter and depth, to conceal the projecting tube end a when it-the guard-
is pushed up to the outer face of the tube plate B. It will be noted that the
guard does not then touch the tube end but stands off from it for the purpose of
leaving a space the use of which will appear further on.
I do not confine myself to the use of a guard made in one piece with the ferrule
as described in the preceding paragraph, inasmuch as the same utility may be
secured by providing a cup shaped ring which is to be driven or screwed on to
the projecting end of the ferrule till its outer edge is up to the plate B..
d is the second or protecting ferrule. The sides of it are parallel, and the
diameter of it is such that they fit tight against the inwardly projecting portions of
the corrugations in the principal ferrule. The outer end of it is trumpet shaped so
that when its edge contacts with the guard there will be an annular space
between them. The use of this second or projecting ferrule may be dispensed
with.
All the surfaces between the principal ferrule on the one hand and the tube and
the tube plate on the other are filled with any suitable material which is a non-
conductor of heat. When a second or protecting ferrule is used, the spaces
between it and the principal ferrule are filled in the same way.
The foregoing describes my invention made and used with boiler tubes of
ordinary pattern, that is with smooth bore tubes, but it is to be distinctly under-
stocd that the invention is not restricted in this respect, inasmuch as it is equally
applicable to those of uneven internal surfaces, such, for example, as the well
known Serve pattern. A Serve boiler tube is characterised by a series of longi-
tudinal ridges projecting from its internal face in the direction of its axis. The
necessary modification in the construction of the principal ferrule is illustrated in
Figure 4. a', a¹ are the Serve ridges. Longitudinal grooves a' are formed in the
ferrule so that the latter can pass the ridges and fit between them close up against
the tube, or the ferrule may be split or slotted for the same. purpose. With the

page_text: exception of the modifications rendered necessary by the Serve ridges, the ferrule
is made and fitted as before described with reference to Figures 1, 2 and 3,
excepting that the corrugations may be omitted should such omission ever be
desirable.
The ferrules described above may be made of any suitable metal and by any
suitable process.
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 :-
1. A ferrule corrugated with parallel corrugations as and for the purpose set
forth.
2. A ferrule having annular or spiral grooves formed in it in such a way as to
provide spaces for non-conducting material, as set forth.
3. The combination in and with a ferrule of corrugations adapted to provide for
its linear contraction effecting its radial expansion, and an annular grooved guard
at one end adapted in respect of size to conceal the projecting end of the respective
boiler tube, as set forth.
4. The combination in and with a ferrule of an annular grooved guard at one end
adapted in respect of size to conceal the projecting end of the respective boiler
tube, as set forth.
5. The combination in and with a ferrule of spaces for non-conducting material
provided by its external conformation, as set forth.
6. The combination of principal ferrule, protecting ferrule and spaces for non-
conducting material, as set forth.
Dated this 28th day of February 1893.
PHILLIPS & LEIGH,
22, Southampton Buildings, Chancery Lane, W.C.,
Agents for the Applicant.