IMPROVEMENTS IN PACKING FOR STUFFING BOXES AND OTHER PARTS OF MACHINERY
Year: 1881

page_text: LETTERS PATENT to Charles Alexander Maynard, of 27, Clement's Lane, iu
the City of London, for an Invention of "IMPROVEMENTS IN PACKING FOR
STUFFING BOXES AND OTHER PARTS OF MACHINERY." A communication
from abroad by Frederick Walton, of Lyons, in the Republic of France.
PROVISIONAL SPECIFICATION left by the said Charles Alexander Maynard
at the Office of the Commissioners, of Patents on the 13th January 1881.
CHARLES ALEXANDER MAYNARD, of 27, Clement's Lane, in the City of London.
"IMPROVEMENTS IN PACKING FOR STUFFING BOXES AND OTHER PARTS OF
MACHINERY." [A communication from abroad by Frederick Walton, of. Lyons, in
the Republic of France:].
This Invention has for its object improvements in packing for stuffing boxes and
other parts of machinery.
For this purpose I prepare a composition consisting mainly of oxidized oil and
powdered asbestos.
The following is a suitable mixture :-
Oxidized oil
New Zealand gum
Resin
Cwt. qrs. lbs.
4 0
0
0 1
0
1
0
Coal naphtha or other solvent in just sufficient quantity to soften the mixture,
say, 10 or 12 gallons.
The oil, gum, and resin, are made into a cement in a steam heated pan, being
well'stirred by mechanical stirrers until complete admixture is obtained, and then
the naphtha is added.
I take 20 lbs. of this composition, and add from 20 to 40 lbs. of powdered asbestos,
using as much as I can combine with the cement without so far reducing the
tenancity of the compound that it will not hold well together when rolled into
sheets.
I use a roller mixer in working the asbestos powder into the cement, and
afterwards I roll out the compound, either alone or upon a cotton or other woven
fabric.
The sheets are cut into strips for use, and for stuffing box packings the strips
are coiled into hollow cylindrical. forms.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles Alexander Maynard in the Great Seal Patent Office on
the 13th July 1881.
CHARLES ALEXANDER MAYNARD, of 27, Clement's Lane, in the City of London.
"IMPROVEMENTS IN PACKING FOR STUFFING BOXES AND OTHER PARTS OF
MACHINERY." A communication from abroad by Frederick Walton, of Lyons, in
the Republic of France.
This Invention has for its object improvements in packing for stuffing boxes and
other parts of machinery..
For this purpose I prepare a composition consisting mainly of oxidised oil and
powdered asbestos.
The oxidised oil which I use is produced by the exposure of boiled linseed oil to
the atmosphere. The oil is spread upon sheets and exposed, as is usual in the
preparation of oil for the manufacture of linoleum. The oxidised oil is crushed
down with stean heated rollers, and is then placed in the mixing pan, together
with other ingredients.
The following is a suitable mixture's
Day, 20
The oil, gum, and resin, are made into a cement in a steam heated pan, being
well stirred by mechanical stirrers until complete admixture is obtained, and then
the naphtha is added.
The pan is closed, and the stirring continued until the composition is cooked,
which will take from six to twelve hours.
I then combine with it as much asbestos generally in powder as the tenacity of
the cement will permit, either by means of a roller mixing machine, or by a radial
mixer of the pug mill type. The quantity of asbestos that can advantageously be
used will vary from equal weights of cement and asbestos to a proportion of
2 cement to 3 asbestos.
If the packing is to be made into sheets without fabric I pass the mass of com-
position several times through a pair of even speeded rollers until I reduce it into
a sheet of the required thickness; it can then be cut up for use. When I roll this
composition on to a fabric use more cement than asbestos, say, four parts of
cement to three parts of asbestos, and I roll the composition on to cotton, linen, and
sometimes wire fabrics.
In some cases I substitute for the oil oxidised by exposure on sheets as described
oil solidified by boiling at a very high temperature, until it finally becomes solid.
It is necessary in this case to employ about 2 to 10 per cent. of dry quick lime or
other powerful dryer when combining it with the asbestos. A good composition
can be made as follows:-
4 cwt. solidified oil
2
-
4
asbestos
>>
30 lbs. quicklime.
If the composition so made be not stiff enough to form sheets more asbestos may
be added, or if too stiff to roll on to or between fabrics coal naphtha may be added
to soften the composition as the solidified oil may be more or less hard or oxidized.
To make packings for glands and piston rods I prefer to proceed as follows:-
I take a piece of wire gauze long enough to make one turn round a mandril, the

page_text: same size as the rod the packing is desired to fit; I then cut a strip of the fabric
on which the asbestos composition has been spread or rolled wide enough to form a
packing of the required depth, and I wind the strip around the wire gauze, which
has been previously put on the mandril. The composition should be in a sufficiently
adhesive condition that the plies may unite under the influence of heat and
pressure. The mandril is heated for this purpose, and rolled on a table to give the
required pressure. The gauze is cut wider than the strip of asbestos fabric, and
notched, so that it can be turned over and made to embrace the plies at the ends
of the packing.
To make washers for steam joints I find one good plan is to take a sheet of a
fabric, cloth, or paper, on which the composition has been rolled, and wrap the
same round a mandril to form a tube, and then I cut washers off the end of the
tube.
Having thus described the nature of the said Invention, and the manner of
performing the same, I would have it understood that I claim as a new and useful
packing for stuffing boxes and other parts of machinery, compositions consisting
mainly of solidified and oxidised oil and asbestos, substantially as described.
In witness whereof, I, the said Charles Alexander Maynard, have hereunto
set my hand and seal, this Thirteenth day of July, in the year of our Lord
One thousand eight hundred and eighty one.
C. A. MAYNARD,
(L.B.)