Improvements in Pipe Couplings..
Year: 1890

page_text: Date of Application, 21st Mar., 1890-Accepted, 31st May, 1890
COMPLETE SPECIFICATION.
Improvements in Pipe Couplings..
1, WILLIAM CARBY C.B. Colonel Royal Artillery, of 15 Anglesea Place, Southampton
in the County of Hants, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
My invention relates chiefly to pipe-couplings of the kind or class commonly known
as flexible couplings for permitting angular notion of the different lengths or
sections of pipe relatively to each other. My said invention also relates to couplings
whereby the pipes are connected in such a manner that they are capable of rotation
about their axes relatively to each other.
In the accompanying drawings
Figures 1 and 2 show, in longitudinal central section lengths or sections of pipes
connected by my improved pipe-couplings so as to form a flexible pipe.
Figure 3 is a side elevation partly in vertical central section showing two pipe
sections connected by my improved coupling so as to be capable of rotation about
their axes relatively to each other.
Figures 4 and 5 are similar views showing other modifications of my invention.
Like letters indicate corresponding parts throughout the drawings.
Each of the joints, shown in Figures 1 and 2 comprises a sector a of a hollow
sphere which is formed on or firmly attached to one end of the pipe or 6. Two
hollow hemispheres e each provided with a hollow semi-cylindrical extension d are
fitted over the said sector a the said hemispheres being so formed that their edges
meet around the said sector and hold or retain the same between then. These
hemispheres are secured together by two or more small clasps e, and further by the
said semi-cylindrical projections or extensions d on the outer sphere of the spherical
joint being fitted into a hollow cylinder or sleeve provided at the end of one of the
pipesborg. The said hollow cylinder or sleeve is retained in position on the
cylinder d, by means of two split pins h passed through the said cylinders, so that no
reasonable amount of strain that may be applied thereto can separate the two parts.
To allow of the pipes connected by the joints as above described being moved or
adjusted relatively to one another a slot c of suitable dimensions is cut or formed in
the outer or covering.sphere c. The pipe or 6', as the case may be, can therefore
yield.or bend, under side or lateral pressure or impact and the strains which would
be set up in a rigid metal pipe are avoided. The cylindrical portion d enclosed in
the sleeve allows of circular or turning motion of one part of the pipe relatively to
another part thereof about the axis of the pipe, without interfering with or inter-
rupting the use of the pipe as a means of supply or discharge of fluids or of solids
such as grain. This turning motion is provided for by cutting or forming on the
exterior of the inner cylinder dan annular groove or channel into which the aforesaid
split pins project and which is of such shape in transverse section as to permit of the
suid cylinder being freely revolved without interference from the split pins whilst as
above stated. longitudinal motion of one cylinder within the other is prevented by
the said split pins or the like.
To make the joint air, gas and water tight, a groove f¹ is cut in the working surface
of the cylindrical portion and a groove is formed around the slot in the
working surface of the spherical portion c of the joint. These grooves may be cut
either on the inner surface of the said cylinder and the sphere c or on the outer
surface of the inner cylinder d and spherical sector of the joint as may be convenient.
In each of these grooves is placed a ring or band of some elastic substance' such as
india-rubber, the thickness of which but slightly exceeds the depth of the groove
added to the space or clearance between the two cylinders or spheres. I prefer that
the amount of this excess shall not be more than one: thousandth of an inch or

page_text: thereabouts, so that, however, slight the pressure exerted to force this excess within
the said space, the same is entirely filled and nothing can pass between the surfaces
of the elastic substance and those of the metal surface which meet or bear one
against the other. The joint will therefore be hermetically sealed, in other words it
will be gas, air or water-tight. The amount of surface of the elastic band or ring
can thus be made so small that the pressure or thrust thereon, will not be more than
a few ounces.
If the said ring or band were made without regard to consistency or uniformity
of the material of which it is composed or too thick to readily enter the space formed
by the groove and clearance, the pressure necessary to cause the same to enter the
said space will be increased and so set up friction, while if the space be not entirely
filled leakage will ensue.
By carefully smoothing and polishing the metal surface in contact with the elastic
band, and correspondingly smoothing the surface of the band the amount of friction
may be very much diminished while on the other hand if the opposite surfaces of the
groove and elastic band are made more or less rough it will ensure a certain amount
of adhesion or grip and the elastic band will be held firmly in position by the friction
set up and by one end butting against the further edge of the metal groove.
I do not however restrict myself to this mechanical means of securing the elastic
substances in its place, but in certain instances prefer to produce adhesion between
the surface of the cylinder and the elastic band or the like by the use of
suitable cement or by chemical compounds or substances which will produce the same
effect.
My improved joint or connection is therefore partly cylindrical and partly
spherical, and can be used as a cylindrical or spherical joint, or as a cylindrical and
spherical joint combined as may be required, the cylindrical joint permitting motion
about the axis of the pipe and the spherical joint giving flexibility to the pipe.
I sometimes make the said joints steam tight by the substitution of metal for
elastic bands in the said grooves. Metals when subjected to heat expand, and such
expansion varies with the metal and with the temperature to which it is subjected.
Therefore taking advantage of such properties and choosing a softer and more rapidly
expanding metal than that of which the joint is made and introducing it in the
groove in lieu of the elastic substance, the expansion effects the rapid filling up of
the clearance or working space between the two metal surfaces, and a practically
steam-tight joint with a minimum of frictional resistance is obtained.
This joint is applicable to all work requiring a movable joint whether for operations
on land, sea or for submarine-work such as deep sea diving operations.
In Figure 3 have shown a modification of my invention wherein the spherical
portion of the coupling is dispensed with and the cylindrical portion only
employed, the latter being constructed and operating substantially as above
described.
Figures 4 and 5 show modifications in which not only is the spherical portion of
the coupling dispensed with but the necessity for the use of the split pin h is obviated
by providing external supports in cases where this is practicable, in line with
the axis of rotation of the parts, the sections of piping being thus securely held
together.
This external support may for instance take the form of counterpoise weights as in
suspended gasaliers.
I sometimes construct a buoyant and watertight air pipe for use in connection with
submarine operations, which pipe is not liable to be injured by the water-pressure
and is formed in lengths or sections connected by joints which permit of the said
sections being moved or adjusted relatively to one another.
This pipe is made in lengths of ten feet, or other suitable lengths as may be found
necessary, and each length or section consists of a metal pipe of the required interior
diameter or area of cross section fitted with ends as above described for the water-
tight joint and being so proportioned as to be buoyant the effect of its weight is
neutralized when immersed in water thus allowing of its being drawn or moved into

page_text: any position without exertion, whatever the depth of water may be at which it is
required for working. This incompressible pipe therefore has the advantage, in
conjunction with a similar discharge pipe, of ensuring a free current of air to a diver
so that he may work as freely in deep water as he could within a few feet of the
surface of the water with the ordinary air pipes.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I wish it understood that
I claim :-
First A pipe coupling-comprising a sector of a hollow sphere enclosed in another
hollow sphere which is formed in two parts connected by suitable clasps or other
fastenings and which is provided with an opening or slot surrounded by a groove
containing metal or India-rubber or other suitable elastic substance substantially as
bereinbefore described, for the purposes specified.
Second-In a hollow spherical joint or pipe-coupling, a pivot comprising an
internal projection on and from the outer sphere, which pivot forms a bearing for the
inner hollow sphere sector, substantially as herein before described, for the purposes,
specified.
Third A pipe-coupling comprising a hollow cylinder formed with a circumferential
or annular groove and enclosed in another hollow cylinder having fixed therein pins
which extend into the said groove, and metal india-rubber or other suitable elastic
substance arranged between the bearing surfaces of the joint substantially as herein-
before described, for the purposes, specified.
Fourth-The modification of my invention wherein I dispense with the pin-and-
groove connection and provide extraneous supports for holding together the two parts
of the coupling whilst permitting relative rotation of the same, substantially as herein-
before described, for the purposes, specified.
Fifth The combination of my spherical and cylindrical joints substantially as
berein before described for the purposes specified.
Sixth The improved flexible pipe constructed substantially as described with
reference to Figures 1 and 2 of the accompanying drawings for the purposes above
specified.
Dated this 19th day of March 1890.
WILLIAM CAREY, C.B., Colonel R.A.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.