Improvements in Pipe Joints."
Year: 1897

page_text: Improvements in Pipe Joints."
I, ALEXANDRE EDMOND THOMINE, of 95 Boulevard Beaumarchais, Paris, in the
Republic of France, do hereby declare the nature of this invention to be as
follows:-
.
This invention relates to a novel method of joining pipes forming part of com-
pressed air systems.
Upon each of the lengths of pipe which it is desired to join, and at some little
distance from their extremity, I form in any suitable manner, preferably by the
use of a mandrel while the work is in a heated condition, a circular boss or projec-
tion. These bosses or projections serve, as will presently appear, as bearing parts
for enabling the necessary pressure to be exerted upon the joint in order to ensure
its tightness.
The extremities of the pipe lengths after they have been made perfectly smooth
and true, are placed opposite one another, but at some little distance, in such a
manner that it is possible to interpose between them a copper ring exactly filling
the interval left free between the two lengths, of pipe.
Instad of employing copper, I may, of course, make use of any other sufficiently
malleable metal.
The ring is internally bored so as to correspond to the internal diameter of the
pipes and it is externally turned to fit the recesses formed in the two collars
In addition, its section is of the form of a ring having the same thickness as the
pipe and surmounted by a dove-tailed portion connecting with the ring by cirves or
fillets.
Upon each pipe end are mounted two movable collars, one outside the circular
projection and the other on the inside of such projections.
These collars are pierced with openings which are arranged opposite tone another
for the passage of bolts. The outside collars are flat whilst the inside collars on
the side next the ring are recessed in such a manner as to enable them to meet.
over the ring, the face of the collars opposite the ring being inclined towards the
pipe. Between each of the inside collars and the ring, annular washers of some
plastic substance are interposed.
The tightening bolts have each four nuts arranged symetrically two and two,
the outside nuts serving for tightening the metallic joints and bearing upon the
collars, the inside nuts serving for tightening the plastic joints and bearing upon
the collars.
The lengths of pipe are placed end to end with the ring interposed and the
collars and annular washers arranged in the manner above described; the
tightening of the metallic joints between the extremities of the pipes and the
ring is first of all effected by means of the outer nuts, then, by means of the inner
nuts the. tightening of the plastic joints which cover and protect the said metallic
oints is carried out.
In cases where a joint has to be re-made, all that is necessary is to effect the

page_text: slackening of the joint by reversing the operation above described, then the ring
is withdrawn as are also the annular plastic washers, by the space left free; by
this same space new washers can he introduced, then a new ring, whereupon the
tightening is again effected as above, described, without its being necessary to
displace the pipes in the least.
This invention relates to a novel method of joining pipes forming part of
compressed air systems.
In order that my invention may be readily and clearly understood, I have
shewn the improved joint, by way of example, in the accompanying drawing, in
which
Figure 1 is a longitudinal section shewing two lengths of pipe connected by
means of my joint and,
Figure 2 represents a transverse section through the said joint.
Upon each of the lengths of pipe A and B which it is desired to join, and at
some little distance from their extremity, I form in any suitable manner, pre-
ferably by the use of a mandrel while the work is in a heated condition, a circular
loss or enlargement. These bosses or projections, which are indicated by the
reference letters a and b in the example illustrated in the drawing, serve, as will
presently appear, as bearing parts for enabling the necessary pressure to be
exerted upon the joint in order to ensure its tightness.
The extremities of the lengths of pipe A and B after they have been made
perfectly smooth and true, are placed opposite one another, but at some little
distance, in such a manner that it is possible to interpose between them a copper
ring C exactly filling the interval left free between the two lengths of pipe.
Instead of employing copper, I may, of course, make use of any other sufficiently
"malleable metal.
+
The ring C is internally bored so as to correspond to the internal diameter of
the pipes and it is externally turned to fit the recesses formed in the two collars G.
In addition, its section is of the form of a ring having the same thickness as the
pipe and surmounted by a dove-tailed portion connecting with the ring by curves or
fillets.
Upon each pipe end are mounted two movable collars, one F outside the circular
projection and the other G, on the inside of such projections.
These collars are pierced with openings which are arranged opposite one another
for the passage of bolts. The collars F are flat whilst the collars G on the side
next the ring are recessed in such a manner as to enable them to meet oven the
ring, the face of the collars opposite the ring being inclined towards the pipe.
Between each of the collars G and the ring, annular washers E of some plastic
substance are interposed.
The tightening bolts H have each four nuts arranged symmetrically two and
two, the nuts h serving for tightening the metallic joints and bearing upon the ĉ

page_text: collars F, the nuts h serving for tightening the plastic joints and bearing upon
the collars G.
The lengths of pipe A and B are placed end to end with the ring C interposed
and the collars and annular washers arranged in the manner above described;
the tightening of the metallic joints between the extremities of the pipes and
the ring C is first of all effected by means of the nuts h, then, by means of the
nuts, the tightening of the plastic joints which cover and protect the said
metallic joints is carried out.
In cases where a joint has to be re-made, all that is necessary is to effect the
slackening of the joint by reversing the operation above described, then the ring C
is withdrawn as are also the annular plastic washers E by the space left free:
by this same space new washers can be introduced, then a new ring, whereupon
the tightening is again effected as above described, without its being necessary
to displace the pipes A and B in the least.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is:-
A joint for compressed air conduits or pipes, comprising a metal ring inter-
posed between the extremities of the lengths of pipe which are to be connected,
such extremities having been previously trued, the said ring forming exteriorly
of the pipes, a projection which is dove-tailed in section, and in combination,
four collars passed upon the pipe ends symmetrically two and two, bne being
beyond and one within a boss or projection formed upon the pipes, the first serving
as bearing joints for effecting the tightening of the metallic joints, the second
for the tightening of the plastic joints, that is to say in short, the method or
device above described by means of which a joint can be re-made between two
lengths of piping without its being necessary to displace any portions of the
piping in the least.
Dated th 20th dose of Ontalon 1807
HASELTINE LAKE & Co.
45, Southampton Buildings, London, W,C. Agents for the Applicant.