Improved Means for Jointing Tubes made of Ductile Metal.
Year: 1897

page_text: Date of Application, 13th May, 1897-Accepted, 17th July, 1897
COMPLETE SPECIFICATION.
Improved Means for Jointing Tubes made of Ductile Metal.
We, JULES GROUVELLE and HENRI ARQUEMBOURG, trading as La Société Jules
Grouvelle et H. Arquembourg, of 71, Rue du Moulin-Vert, Paris, in the French
Republic, Manufacturers, 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:-
The object of our present application is to describe with the assistance of the
accompanying drawing, and to claim the improvements conceived by us, which render
it possible, by simply putting end to end and pressing together the worked ends of
tubes made of ductile metal, to secure joints which are tight under the highest
pressure, the said joints being thus quickly formed without the interposition of any
packing, or adventitious material, and, if necessary or desirable, at the place where
the tubes are to be used.
As will
Figs. 1 and 2 of the accompanying drawing are, respectively, a sectional elevation
along the line 1-1 in Fig. 2, and a corresponding plan view. (It should be understood
that the principal dimensions of these figures have only to be increased, or diminished,
in a determined proportion, according to the variations in the size of the internal
diameter of the tubes to be joined, and in the thickness of the said tubes).
be seen in the figures referred to above, A and B are the two ends of the tubes to be
joined, and, to these ends, two flanges C, D are freely applied, the said flanges having
holes bored in them for receiving the screw-bolts. In the adjacent faces of the
flanges C, D, are formed annular grooves, c, d, the curved parts of the profiles of the
said grooves corresponding to rounded shoulders, c', d', which abut against the backs
of lips a, b, also rounded, at the extremities of A and B. (These lips are preferably
formed with a preliminary annealing of the ends of the tubes to be joined, in alt
cases where the quality of the ductile metal to be employed cannot but gain in
consequence of such annealing, having regard to the final result to be obtained).
From the foregoing it will be easily understood that, the various parts occupying
the positions indicated in the accompanying drawing, it will be sufficient, for forming
the required joint, to tighten the bolts in such a manner as to squeeze the lips a, b
one against the other, according to their circle of contact. (In the example given,
the form of the curved part of the generating line of the revolving surfaces of the
shoulders c, d, and of the lips a, b, corresponds with that of a part of a circumference;
but it is obvious that the said form nay be varied, so to speak, to infinity, according
to the destination of the joints to be formed, and to the nature of the ductile metal
to be worked).
It will be observed that the bolts illustrated in the accompanying drawing are of a
stout pattern in order to secure, the powerful pressing required by the formation of
the joints in question, whilst guiding the flanges very surely in relation to one
another; and, further, that the said bolts are approached as near as possible by the
surfaces between which the pressing has to be effected, which has the effect of
facilitating this pressing and of permitting the use of flanges of relatively little

page_text: thickness and small diameter,-all most favourable conditions. If, even under these
conditions, the flanges should cause inconvenience, they may be replaced by two
screw-unions freely applied to the ends of the tubes to be joined, and provided in a
similar manner with annular grooves and rounded shoulders.
Finally, it will be easily understood that the tools for working the ends of the
tubes to be joined into the form of rounded lips might be conceived in many ways.
We confine ourselves here however to the following idea which bears specially on the
forming of joints at the place where the tubes are to be used, of which mention has
been made above. From this special point of view, it is, in fact, desirable that the
tools in question should be light and not cumbersome; thus, for tubes of small or
medium internal diameter, there will be no difficulty under this head, and it will be
the same as regards tubes of large internal diameter, and, consequently of great
weight, the inertia resulting from this heavy weight being simply brought into effect.
It is also proper to remark, always from the same special point of view, that the lips
of tubes of large internal diameter may be formed in stages, in place of by a single
stroke, as may be done for tubes of small or medium internal diameter.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, we claim :-
The improved method of jointing, end to end, tubes made of ductile metal,
substantially as herein described, and consisting in expanding the extremity of each
pipe so as to form a rounded lip and applying flanges or unions the adjacent faces of
which are provided with annular grooves and rounded shoulders, the latter abutting
against the backs of the rounded lips formed on the extremities of the tubes, so that,
when the flanges or unions are tightened, the rounded lips are forced into intimate
contact and secure a tight joint without the intervention of packing material.
Dated this 13th day of May 1997