IMPROVEMENTS IN PACKING FOR STEAM AND OTHER MACHINERY.
Year: 1871

page_text: LETTERS PATENT to Robert Baird Lindsay, of Glasgow, in the
County of Lanark, North Britain, Engineer, for the Invention of
"IMPROVEMENTS IN PACKING FOR STEAM AND OTHER MACHINERY.
"
Sealed the 28th November 1871, and dated the 30th May 1871.
PROVISIONAL SPECIFICATION left by the said Robert Baird Lindsay
at the Office of the Commissioners of Patents, with his Petition,
on the 30th May 1871.
I, ROBERT BAIRD LINDSAY, of Glasgow, in the County of Lanark,
North Britain, Engineer, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN PACKING FOR STEAM AND OTHER MACHINERY," to
be as follows, that is to say:—
This Invention has for its object to obtain a packing for steam and
other machinery, which, whilst acting efficiently with the least possible
friction, is durable and requires little attention.

page_text: The improved packing is formed by winding a spun or unspun yarn
or strand of hemp, flax, or other suitable fibrous material round a
mandril or metal core of the size of the piston rod or other piece of
machinery to which it is to be applied, and between flanges or washers
placed to correspond to the desired depth as measured along the
mandril. The wound material is then subjected to strong pressure in a
mould shaped internally to give the desired form to the packing.
The packing material is, by preference, saturated or dressed with a
mixture of tallow and plumbago either before or after being wound, and
may be used either as an entire ring or, as is preferred, may be cut
through obliquely at two or more equidistant parts with the view of its
adapting itself better and more uniformly all round to the rod or other
piece working through it.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Baird Lindsay in the Great Seal Patent
Office on the 29th November 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
BAIRD LINDSAY, of Glasgow, in the County of Lanark, North Britain,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of May, in the year of
our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Robert Baird Lindsay, Her special
licence that I, the said Robert Baird Lindsay, my executors, adminis-
trators, and assigns, or such others as I, the said Robert Baird Lindsay,
my executors, administrators, and 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 "IMPROVEMENTS
IN PACKING FOR STEAM AND OTHER MACHINERY," upon the condition (amongst
others) that I, the said Robert Baird Lindsay, my executors or adminis-

page_text: trators, by an instrument in writing under my, or their, or one of their
hands and seals, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be per-
formed, 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
Baid Letters Patent.
NOW KNOW YE, that I, the said Robert Baird Lindsay, 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 in writing, reference being had to the
accompanying Drawings, that is to say:-.
My said Invention has for its object to obtain a packing for steam
and other machinery, which, whilst acting efficiently with the least
possible friction, is durable and requires little attention.
And in order that the manner of making my improved packing may
be properly understood, I hereunto append a sheet of explanatory
Drawings, to be herein-after referred to, and representing the arrange-
ment of apparatus which I prefer to use for that purpose, but to which
I by no means restrict myself. In these Drawings the same reference
numerals are used to mark the same or like parts wherever they are
repeated.
My improved packing is formed by winding a spun or unspun yarn
or strand of hemp, flax, or other suitable fibrous material round a
mandril or metal core 1, such, for example, as is shown in axial section
in Figure 1, and which is of the size of the piston rod or other piece of
machinery to which it is to be applied. When winding the fibrous
material the metal core 1 is fixed on a spindle 2, with overlapping and
projecting discs 3, 4, at each end, and with intermediate washers or
spacing rings 5, 6, according to the number of rings of packing to be
formed on a given length of core. Thus the example shown in Figure 1
is arranged for forming three rings of packing by winding the fibrous
material in the spaces 7, 8, 9.
The packing material may be saturated or dressed with a mixture of
tallow and plumbago either before or after being wound, but I prefer
to first heat it in tallow, and, after wringing out the excess of tallow, to
dress it with powdered plumbago before winding it.

page_text: .
The wound material is subjected to strong pressure in a mould shaped
internally to give it the desired form. A suitable mould is shown in
plan in Figure 2 and in axial section in Figure 3, and consists simply
of a cylinder 10, with bottom and top rings 11, 12. The bottom ring 11
is shaped to support both the cylinder 10 and the core piece 1, which
last is shown in its place as when a set of three packing rings are being
compressed (in the annular spaces 7, 8, 9). A small ring 13 resting on
the base ring 11 fits in between the cylinder 10 and core piece 1, and
can be changed to suit packing rings of different radial thicknesses.
The top ring 12 fits in between the cylinder 10 and the core piece 1,
and rests on the top of the uppermost packing ring (7). The mould or
cylinder 10, with its contents arranged as described, is put between the
follower and platen of a hydraulic or other suitable press, and the
pressure acting on the ring 12 is by it communicated to the rings of
packing material. I have found a pressure equal to about 5,600 pounds
per square inch of the annular area of the packing to be suitable and to
give good results, but less or more may be employed according to cir-
cumstances. The compressed rings of packing are removed from the
mould by substituting for the lower ring 11 separate supports for the
core piece 1 and cylinder 10, and applying pressure by means of a
sufficiently long annular plunger in place of the upper ring 12, so as
to force the rings downwards. The intermediate rings 5, 6, and the
bottom rings 13, 11, are grooved and notched, as shown, to provide a
means of escape for excess of tallow which the compression causes to
exude from the fibrous material.
My improved packing material may be used in the form of complete
rings; I, however, prefer to have each ring cut through obliquely at
two or more equidistant parts, with the view of its adapting itself better
and more uniformly all round to the rod or other piece working through
or past it.
Asbestos may be used as the fibrous material of which to make my
improved packing, in which case the dressing with plumbago will not be
required.
Having thus particularly described my said Invention, and the
manner of performing the same, I have to state that I do not restrict
myself to the precise details herein described, but that what I believe
to be novel and original and claim as the Invention secured to me by

page_text: the herein-before in part recited Letters Patent is, the making of
packing for steam and other machinery, substantially in the improved
manner herein-before described.
In witness whereof, I, the said Robert Baird Lindsay, have here-
unto set my hand and seal, this Twenty-eighth day of November,
in the year of our Lord One thousand eight hundred and seventy-
one.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
R. B. LINDSAY. (L.S.)