IMPROVEMENTS IN PLUGS AND FERRULES FOR THE TUBES OF STEAM GENERATORS
Year: 1872

page_text: LETTERS PATENT to Frederick St. George Smith, of Drogheda, Ireland,
Engineer, for the Invention of "IMPROVEMENTS IN PLUGS AND FERRULES
FOR THE TUBES OF STEAM GENERATORS."-A communication from abroad
by Robert Avis Copeland, of Ninety-three, Liberty Street, New
York, U.S.A.
Sealed the 1st November 1872, and dated the 28th August 1872.
PROVISIONAL SPECIFICATION left by the said Frederick St. George
Smith at the Office of the Commissioners of Patents, with his
Petition, on the 28th August 1872.
I, FREDERICK ST. GEORGE SMITH, of Drogheda, Ireland, Engineer, do
hereby declare the nature of the said Invention for “IMPROVEMENTS IN
PLUGS AND FERRULES FOR THE TUBES OF STEAM GENERATORS," a communication
to me from abroad by Robert Avis Copeland, of Ninety-three, Liberty
Street, New York, U.S.A., to be as follows:-
This Invention relates to certain peculiar constructions and arrange-
ments of plugs and ferrules to be applied to the tubes of steam generators
for the purpose of plugging up and stopping leaks in such tubes, whether

page_text: in the ends thereof or in the body, and consists of a short hollow metal
cylinder, which when used as a plug is formed with one end closed, so
that when inserted into the end of a tube it will close up the passage,
but when used as a ferrule the said short hollow cylinder is left open at
both ends, so that when inserted into the boiler tube it will still leave
the passage open. A flange is formed on the outer end of the plug or
ferrule, and the inner side of this flange is grooved for the purpose of
containing any suitable cement or packing, whilst on the outer face of
the said flange lugs are formed for facilitating the turning of the plug or
ferrule after it has been inserted into the end of the tube. Grooves of
gradually increasing depth which may or may not be dovetailed, are
formed round the external cylindrical surface of the plug or ferrule
into which grooves are inserted loose sliding wedges curved to corre-
spond or nearly so with the external cylindrical-surface of the plug
or ferrule, and toothed or serrated on their external surface in order to
give them a firm hold upon the interior surface of the tube. The said
grooves are portions of spirals or are made at a slight inclination or
angle to the axis of the plug or ferrule.
When inserted into the tube end and turned round therein the wedge
pieces by engaging with the metal of the tube will remain stationary,
but the plug or ferrule by turning round within them will not only be
tightened inside the tube but will by the screw action of the spiral or
inclined grooves be drawn inwards so as to bring the inner packed face
of the flange hard up against the tube end and tube plate, thereby in
the case of the ferrule effectually preventing leakage in the ends of the
tubes by making good any defect in the joint between the tube and the
tube plate, also acting as a stay to the tube plate, and in certain cases
serving to reduce superfluous draught through the tube.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Frederick St. George Smith in the Great Seal 30
Patent Office on the 28th February 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
ST. GEORGE SMITH, of Drogheda, Ireland, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-eighth day of August, in the 3

page_text: year of our Lord One thousand eight hundred and seventy-two, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Frederick St. George Smith, Her
special license that I, the said Frederick St. George Smith, my execu-
tors, administrators, and assigns, or such others as I, the said
Frederick St. George Smith, my executors, administrators, or assigns,
should at any time agree with, and no others, from time to time and
all times thereafter during the term therein expressed, should and law-
fully might make use, exercise, and vend, within the United Kingdom
of Great Britain and Ireland, the Channel Islands, and Isle of Man,
an Invention for "IMPROVEMENTS IN PLUGS AND FERRULES FOR THE TUBES
OF STEAM GENERATORS," a communication to me from abroad by Robert
Avis Copeland, of 93, Liberty Street, New York, United States of
America, upon the condition (amongst others) that I, the said Frederick
St. George Smith, my executors or administrators, by an instrument in
writing under my hand and seal, should particularly describe and ascer-
tain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Frederick St. George Smith, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement, reference being had to the accom-
panying Drawings, and to the letters and figures marked thereon, that
is to say:-
This Invention relates to certain peculiar constructions and arrange.
ments of plugs and ferules to be applied to the tubes of steam generators
for the purpose of plugging up and stopping leaks in such tubes whether
in the ends thereof or in the body.
And in order that the said Invention may be fully understood, I
shall now proceed more particularly to describe the same, and for that
purpose shall refer to the several Figures on the annexed Sheet of
Drawings, the same letters of reference indicating corresponding parts in
all the Figures.
Figure 1 of my Drawings represents a sectional elevation of my
improved plug.

page_text: Figure 3 is a sectional elevation of my improved ferrule, and Figure 4
is a perspective view thereof.
Figures 5 and 6 are details of the wedges herein-after referred to.
A is a short hollow metal cylinder, which when used a as plug is
formed with one end closed (Figures 1 and 2, so that when inserted into
the end of a tube it will close up the passage, but when used as a ferrule
the said short hollow cylinder is left open at both ends (see Figures 3
and 4), so that when inserted into the boiler tube it will still leave the
passage open. A flange a is formed on the outer end of the plug or
ferrule and the inner side of this flange is grooved or undercut, as shewn
at 6 for the purpose of containing any suitable cement or packing,
whilst on the outer face of the said flange lugs c, c, are formed for
facilitating the turning of the plug or ferrule after it has been inserted
into the end of the tube. Grooves d, d, of gradually increasing depth
which may or may not be dovetailed, are formed round the external
cylindrical surface of the plug or ferrule, into which grooves are inserted,
the loose sliding wedges e, e, (Figures 5 and 6) curved to correspond or
nearly so with the external cylindrical surface of the plug or ferrule, and
toothed or serrated on their external surface, as shewn in the Drawings,
in order to give them a firm hold upon the interior surface of the tube.
The said grooves d, d, form portions of spirals or are made at a slight
inclination or angle to the axis of the plug or ferrule, as will be seen on
referring to Figures 2 and 4. When inserted into the tube end and
turned round therein, the wedge pieces e, e, by engaging with the metal
of the tube will remain stationary, but the plug or ferrule A by turning
round within them will not only be tightened inside the tube but will
by the screw action of the spiral or inclined grooves be drawn inwards,
so as to bring the inner packed face 6 of the flange hard up against the
tube end and tube plate, thereby in the case of the ferrule effectually
preventing leakage in the ends of the tubes by making good any defect
in the joint between the tube and the tube plate, also acting as a stay
to the tube plate, and in certain cases serving to reduce superfluous
draught through the tube.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that what I consider

page_text: to be novel and original, and therefore claim as the Invention secured to
me by the herein-before in part recited Letters Patent is, the construction
and use of plugs or ferrules, having a grooved flange at one end provided
with means for turning the same, and having spiral grooves of gradually
increasing depth made circumferentially in their cylindrical surfaces for
the reception of serrated or toothed wedges of a curved form, the whole
being arranged and operated substantially as and for the purposes herein
before described and illustrated by my Drawings.
In witness whereof, I, the said Frederick St. George Smith, have to
this my Specification, set my hand and seal, this 25th day of
Feby., One thousand eight hundred and seventy-three.
F. ST. GEO. SMITH. (L.S.)