AN IMPROVED PACKING. FOR THE TUBES OF SURPACE CONDENSERS AND OTHER SIMILAR PURPOSES
Year: 1868

page_text: LETTERS PATENT to David Marshall, of Leith, in the County of Mid
Lothian, North Britain, for the Invention of "AN IMPROVED PACKING.
FOR THE TUBES OF SURPACE CONDENSERS AND OTHER SIMILAR PURPOSES."
Sealed the 23rd March 1869, and dated the 7th October 1868.
PROVISIONAL SPECIFICATION left by the said David Marshall at the
Office of the Commissioners of Patents, with his Petition, on the
7th October 1868.
I, DAVID MARSHALL, of Leith, in the County of Mid Lothian, North
Britain, do hereby declare the nature of the said Invention of "AN
IMPROVED PACKING FOR THE TUBES OF SURFACE CONDENSERS AND OTHER SIMILAR
PURPOSES," to be as follows, that is to say:
This Invention consists essentially of an improved packing to be used
in making the joints of tubes in surface condensers water and steam-
tight, which packing may also be used for other similar purposes.
This improved packing consists of an india-rubber ring or tube having
an annular groove or space formed at one end between the outer and
inner periphery of the ring or tube so as to form a kind of cupped ring,

page_text: the edges of which will spread out under pressure, and form a water and
steam tight joint.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said David Marshall in the Great Seal Patent Office
on the 7th April 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
MARSHALL, of Leith, in the County of Mid Lothian, North Britain, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of October, in the
year of our Lord One thousand eight hundred and sixty-eight, in the
thirty-second year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said David Marshall, Her special
license that I, the said David Marshall, my executors, administrators,
and assigns, or such others as I, the said David Marshall, my executors,
administrators, or assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully 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 "AN IMPROVED
PACKING FOR THE TUBES OF SURFACE CONDENSERS AND OTHER SIMILAR PURPOSES,"
upon the condition (amongst others) that I, the said David Marshall, by
an instrument in writing under my hand and seal, should particularly
describe and ascertain 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 David Marshall, 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 accompanying
Drawings, and to the letters and figures marked thereon, that is to
say:-
My said Invention consists essentially of an improved packing to be

page_text: used in making the joints of tubes in surface condensers water and steam
tight, which packing may also be used for other similar purposes.
This improved packing consists of an india-rubber ring or tube, or it
may be formed of other suitable and similar elastic material having an
annular groove or space formed at one end between the outer and inner
periphery of the ring or tube so as to form a kind of cupped ring, the
edges of which will spread out under pressure, and form a water and
steam tight joint.
And in order that my said Invention may be properly understood I
shall now proceed more particularly to describe the system, mode, or
manner in or under which the same is or may be used or practically
carried into effect, reference being had to the several Figures upon the
explanatory Sheet of Drawings which I have hereunto appended, and in
which corresponding parts are indicated by corresponding letters of
reference, that is to say:-
Figure 1 is a partial transverse section of a surface condenser in which
the water passes through the tubes, showing the manner in which my
Invention is practically applied. In this Figure a quantity of tubes
marked B are inserted into surface condenser tube plates C, and having
cach joint made water-tight by means of my improved packing as
represented by the dark sections marked A.
Figure 2 is an enlarged section of part of a surface condenser tube
plate, and Figure 3 is a corresponding elevation of part of a surface
condenser tube plate.
In Figure 2 my improved packing is marked A and shown in its
proper position relative to the tubes B, and the tube plate C of the
condenser inserted into a recess formed in the plate and surrounding the
inserted tubes B. Immediately that the packing becomes affected by
the introduction of either water, steam, or other liquid or fluid into the
annular space f between the outside and inside rings d and e, the
pressure acting upon their surfaces expands the rings, thus forcing the
two outer surfaces tightly against the metal of the condenser tube plate
and the tube in proportion to the pressure bearing upon them, thereby
securing a simple and perfectly water-tight or steam-tight joint.
In Figure 3 is shown in front elevation several surface condenser tubes
with the packing encircling them; the circles marked e represent the

page_text: inside ring of the packing which acts upon the tube, and those marked d
the parts which bear against the recess in the tube plate. In Figure 2
the annular space extends to about one-half the depth of the packing,
but the depth may be varied as found necessary. In this Figure also.
is shown the upper ring with the inner lip e of greater length than the
outer lip d, a form which may sometimes be adopted, and the ring
around the lower tube is shown with the lip e shorter than the outer
lip d. In applying my improved packing to tubes which are surrounded
with water or other fluid as in the case of those condensers wherein the
water is on the outside of the tubes and the steam passes through them
it becomes necessary to alter the position of the cupped ring; this may
be effected as shown at Figure 4, which represents a tube thus sur-
rounded by water. In this case a double tube plate is employed, in
the inner one of which A the holes are bored large enough to receive
the packing ring c, c, and after the rings are put in the outer tube
plate B is put on and secured by bolts so that it prevents the rings from
being forced out when acted upon by the water or other fluid. In place
of forming the rings with two lips one of the lips may be nearly or
wholly dispensed with.
Having now described the nature of my said Invention, and the
manner in or under which the same is or may be used or practically
carried into effect, I would observe in conclusion that what I consider
novel and original, and therefore claim as the Invention secured to me
by the herein-before in part recited Letters Patent is, the formation or
construction of packing rings having an annular space therein as herein-
before described and shown on the accompanying Sheet of Drawings, or
any mere modification thereof.
In witness whereof, I, the said David Marshall, have hereunto
set my hand and seal, this Twenty-seventh day of March, One
thousand eight hundred and sixty-nine.
DAVID MARSHALL. (L.s.)