IMPROVEMENTS IN THE MANUFACTURE OF FLEXIBLE AND OTHER TUBES
Year: 1863

page_text: LETTERS PATENT to Isaac Blue Harris, of the North British Rubber
Company (Limited), Castle Mills, Fountain Bridge, Edinburgh, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF FLEXIBLE AND OTHER
TUBES."
Sealed the 1st December 1863, and dated the 15th June 1863.
PROVISIONAL SPECIFICATION left by the said Isaac Blue Harris at
the Office of the Commissioners of Patents, with his Petition, on the
15th June 1863.
I, ISAAC BLUE HARRIS, of the North British Rubber Company (Limited),
Castle Mills, Fountain Bridge, Edinburgh, do hereby declare the nature of
the Invention for "IMPROVEMENTS IN THE MANUFACTURE OF FLEXIBLE AND OTHER
TUBES," to be as follows:-
This Invention has for its object "Improvements in the Manufacture of
Flexible and other Tubes." In order to produce a flexible waterproof tube or
hose, I take a seamless woven tube, and I coat it externally with a compo-
sition of india-rubber and sulphur. This composition can be applied in
several different ways; it may be dissolved, and in this state spread upon the
woven tube in several coats. Or the composition, when in a plastic state, may
be applied by means of callendering rollers; or it may be applied by a forcing
machine, as telegraph wires are commonly covered with gutta percha, or
strips of the india-rubber compounds may be lapped round the woven tube
by hand. I also line the woven tube with india-rubber and sulphur

page_text: compound; to do this I make a tube of the compound by any convenient
means, and introduce this tube into the woven hose; I place a small quantity
of water within the tube of compound, and having stopped the ends thereof,
I proceed to vulcanize the whole. The heat used in this process vaporizes
the water, and the pressure of the steam generated expands the tube of com-
pound, and forces it firmly against the interior of the woven tube and into all
the crevices thereof, and whilst so held it becomes vulcanized. Or in place of
vulcanizing in this manner, the woven tube coated and lined may be drawn
step by step through a heated tube, one end of the hose being stopped as
before, and air or other liquid under pressure being forced in at the other end
by means of a nozzle fitted into it; metal and other rigid tubes may be lined
with vulcanized india-rubber in a similar manner. By similar means also
flexible and other tubes may be coated and lined with vulcanite. Compounds
of gutta percha and sulphur may be substituted for india-rubber compound,
but not, I believe, advantageously.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Isaac Blue Harris in the Great Seal Patent Office on the
11th December 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ISAAC
BLUE HARRIS, of the North British Rubber Company (Limited) Castle
Mills, Fountain Bridge, Edinburgh, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifteenth day of June, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Isaac Blue Harris, Her special licence that I, the said Isaac Blue
Harris, my executors, administrators, and assigns, or such others as. I, the
said Isaac Blue Harris, 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 THE MANUFACTURE OF FLEXIBLE AND OTHER TUBES," upon the
condition (amongst others) that I, the said Isaac Blue Harris, my executors,
or administrators, 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

page_text: performed, and cause the same to be filed in the Great Seal Patent Offico
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Isaac Blue Harris, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
This Invention has for its object improvements in the manufacture of
flexible and other tubes, and consists in producing a flexible waterproof tube
or hose by lining and coating a woven tube with vulcanized india-rubber in
the following manner: Into the woven tube a tube of somewhat smaller size
and made of india-rubber composition, suitable for vulcanizing, is placed; this
inner tube is expanded by fluid pressure and vulcanized. Before vulcanizing,
however, a coating is applied to the exterior of the hose. Whilst it is distended
by fluid pressure a strip of india-rubber is lapped round the hose and caused
to adhere; sound joints being made, the vulcanizing is effected whilst the
hose is kept distended by fluid pressure. Also, according to my Invention, I
line in a similar manner metal or other rigid tubes with vulcanized india-
rubber. By similar means also flexible and other tubes may be coated and
lined with vulcanite, the compound being somewhat modified, and more heat
employed, as is well understood by india-rubber manufacturers. Compounds
of gutta percha and sulphur may be substituted for india-rubber, but not,
I believe, advantageously.
The following is the manner in which I prefer to proceed:-I take, by pre-
ference, the common woven flax or cotton (seamless) hose; after the woven
hose has been dried it is passed through a friction calendar first on one side
and then on the other, by which an exceedingly thin coat of rubber is laid
upon the two sides, and which enables the rubber cover to readily attach itself
and remain permanently on the hose. This may also be attained by cementing
the hose, but the friction coat is preferred. A tube of compounded rubber is
made up in the usual manner; this tube should be considerably less than the
inside of the woven hose to admit of its being easily drawn through. In
making up the tube a narrow tape is made to adhere inside it, and this tape is
left sticking out of the tube for a few inches at the end. The woven hose is
then pushed through an iron pipe of greater diameter than itself. The hose
being of a stiff substance, readily goes through and assumes the round form of
the tube. The hose as it comes from the weaver is pressed flat, thus
but by inserting it into the iron pipe it opens, so as to allow the introduction
of the tube of compound; a wire is then run through the pipe and is caught

page_text: into the piece of tape which protrudes from the inside of the rubber tube. By
drawing the wire the tube follows it, and is thus readily pulled through the
woven hose. This can also be accomplished by suspending the hose in a tower
or hoist way and lowering the rubber tube through it (by weighting' the tube).
The woven hose with the rubber tube inside is then drawn out of the interior
of the iron pipe. The rubber tube is gently expanded at its two ends by
conical expanders until it has for the space of 1 to 2 inches attained the
full size of the interior of the hose. Hollow metal plugs having cocks in them
are then introduced into the ends of the hose, and exterior clamps are put on
the outside, so as to bind the ends of the hose securely to the plugs. One of
the hollow metal plugs is then coupled with a pipe, through which cold or
warm water or steam can be supplied at pleasure. The cock at the other end
is left open.
The cold water valve is then opened, and the water rushes
through the tube, driving the air before it out of the open cock at the other end
of the hose. As soon as the water comes out of the open cock it is closed, and
the tube receives the pressure of cold water; this should be about 5 lbs. per
square inch.
The pressure of the water gently dilates the rubber tube without
breaking it, and in a few minutes it will be found to have expanded itself to
the full size of the interior of the woven hose. The cold water valve is then
shut, and the cock in the further end of the hose is opened. The steam valve
is then opened, the steam rushes through the hose driving the cold water out,
and as soon as the steam shows itself at the open cock this is closed and the
steam valve kept so as to give a pressure of about 40 lbs. to the square inch.
The rubber tube becoming softened by the heat and pressed by the steam is
driven well into the woven hose, expelling all the air which was between it and
the hose. This pressure of steam is allowed to remain from 20 to 30 minutes.
Again, the cock at the further end is opened, the steam valve is shut, and the
warm-water valve opened. As soon as the warm water shows itself the open
cock is closed, and the pressure of warm water increased until the hose
becomes firm and hard as if on a metal mandril. Whilst under this pressure
the cocks are closed tight, the whole is detached from the system of water and
steam pipes, and taken to another table. A strip of rubber compound the
length of the hose is then laid on the table, and the hose is rolled on to it;
this strip is wide enough to embrace the circumference of the hose, and thus
forms the rubber cover; or the covering strip may be applied spirally around
the hose. The better plan is to lay the hose on the table and ro!! the cover on
it, turning the hose as the rolling progresses. Care is taken in covering the
hose to exclude all air from between the cover and the hose, and the surface
is carefully rolled with a small hand roller as the covering progresses.
The

page_text: warm water inside. the nose serves to soften the thin coat of rubber which was
put on by the callender, so that the rubber cover readily adheres to it, whilst
the pressure of the water distends the hose, so as to allow the hand roll to be
used in rolling on the cover. The covering operation being complete, one of the
cocks is opened, and about half the water is allowed to escape, when it is again
shut, care being taken to allow no air to enter whilst drawing off the water.
The hose is now ready for vulcanizing; this may be done by any of the well-
known processes. The preferable method is to put it into a curing heater the
same length as the. hose (so as not to coil the hose). When closed the heat is
raised gradually for one hour until it reaches 300 degrees Fahrenheit; after
standing about 30 minutes at 300° it is withdrawn, the cocks are opened, the
water entirely discharged. During the process of vulcanization the high heat
vaporises the water within the hose and creates a pressure, which keeps the
hose out round, and it vulcanizes in that much desired shape. The clasps at
each end are now.unscrewed and the plugs withdrawn;" the ends which the
plugs and clasps held are cut off, and the hose, after being dried and coiled up
is ready for the market. By this process there is obtained a strong seamless
hose, lined inside and outside with rubber, round in form, and lighter and
cheaper than if made as heretofore practised. By the various expanding pro-
cesses the air is got rid of between the tube and the hose, which would other-
wise "blow up" during the vulcanization. The tape which was inside the
tube comes away in the "curing." In case spiral wire is wanted inside the
hose, such as is usually employed for "suction hose," the wire is spun upon an
iron mandril of such diameter that the whole is smaller than the inside of the
hose. The ends of the wire are secured to the mandril, so that the wire is
held tight on the whole length of the mandril. The mandril with the wire on
it is then put through the vulcanized hose, constructed as above described, and
the ends are let go, the whole length of spiral wire then springs away from the
mandril, and presses hard against the inside of the hose, and the mandril is
withdrawn, leaving the wire in the hose. Embedded suction hose can be
made by having the wire coated with rubber.
In coating the inside of metal pipes the rubber tube is drawn through the
pipe in any convenient way, plugs secure the ends and connect one of them with
a water and steam supply pipe, as already described. The tube is distended by
cold water, and this is followed by the steam under pressure. The metal pipe
during this operation is kept upright. The water fills first at the bottom or lower
end and distends the rubber tube. The air is gradually worked out at the top
through a very small hole made in the pipe close to the plug. When the
water has fully distended the rubber tube against the inside of the iron pipe,

page_text: J
and the air has been expelled from between the tube and the pipe,, the steam
is admitted. The vulcanization can then be carried on at once by allowing the
steam to remain at a pressure of 60 lbs. for about the same length of time as
described for the curing of the hose. After removal of the plugs. the interior
will be found thoroughly vulcanized and adhering firmly to the inside of the
metal pipe.
303
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I would remark that the degrees of pressure and heat, and the times. during
which the pressure and heat are maintained may be varied to, some, extent,
according to sizes of hose and other circumstances, as the manufacturer will
understand.
In witness whereof, I, the said Isaac Blue Harris, have hereunto set.my
hand and seal, this Second day of December, in the year of our Lord
One thousand eight hundred and sixty-three.
ISAAC BLUE HARRIS.. (L.S.)