Assembly for a branch plug of a derivation onto a fluid transport pipe
The present invention relates to a device simplifying the
installation of a branch plug onto a fluid transport pipe,
notably from the upper part of a pit.
It is often necessary to install branch or derivation
plugs onto pipes, such as gas or water distribution pipes. In
cities, it is desired to dig a pit with limited dimensions,
notably in order to reduce the trouble caused to the
pedestrian or vehicle traffic. To this end, it is as far as
possible avoided to dig a trench for enabling a person to go
down to the bottom of it and, when it is possible, an
installation from the upper part of a pit is systematically
favored.
When the pipe and the branch plug are made of a
thermofusible material, such as polyethylene, the fixation of
the plug to the pipe is generally carried out with a welding
process. The branch plug body, in the form of a saddle, is
then provided with an electric resistor connectable to an
electric supply for fusion welding the plug basis onto the
part of the pipe portion in contact with this basis. In order
to carry out a correct welding operation, it is necessary that
the branch plug be hold tight against the pipe. To this end,
it is provided a lower saddle placed under the pipe and to
which the upper saddle of the branch plug body is attached.
The connection between the branch plug body provided with
welding means and the lower saddle enables to provide a
tightening against the pipe in well-defined and reproducible
conditions, which thus enable to obtain branch plug/lower
saddle assemblies complying with the various regulations.
The realization of a connection thus systematically needs
to bring the lower and upper saddles closer to one another,
the upper saddle being firmly fixed to the branch plug. Branch
plugs can be currently provided with various types of saddles:
these saddles can be rigid or articulated in relation to one
another, or linked so as to form a semi-rigid assembly, etc.
The installation of the lower saddle of known branch plugs is
not easy, whether it is done remotely, from the upper part of
the pit, or nearby, when the pit dimensions enable the
operator to come sufficiently near the pipe.
In order to install the lower and upper saddles of a
branch plug, a known solution is described in the patent
application published under the number FR 2 768 213. The
described device is not satisfactory in that the operations
for installing a branch plug are still complex. Thus, when the
operator works nearby, he/she is forced to manually bring the
lower saddle under the pipe before fixing both saddles
together. When the conditions enable to work from the upper
part of the pit, it is known to use a tool such as described
in the patent application published under the number
FR 2 869 089.
This tool comprises a support, to which means for holding
the upper saddle are connected, as well as a shoe rotatively
articulated to the support. Actuating means, such as a jack,
enable to move the shoe between an introduction position and a
pressure position. Thus, the tool enables to automatically
install the lower saddle from the upper part of the pit, and
hold it by means of the shoe while firmly fixing both saddles
together (for example by means of screws and bolts).
Such a tool, although it enables to obtain a satisfactory
installation quality for the branch plugs, is all the same
heavy, cumbersome and onerous. Notably, the space for using it
needs a sufficiently wide pit for laterally freeing the
articulated shoe.
The invention aims at facilitating the installation of a
branch plug and at reducing the cost of it while reducing the
necessary dimensions of the pit. More precisely, the invention
aims at providing a device for automatically installing the
lower saddle in a simple and quick manner and for temporarily
holding it until it is fixed to the upper saddle.
Thus, the invention relates to an assembly for a branch
plug of a derivation onto a portion of a fluid transport pipe,
notably a gas transport pipe, characterized in that it
comprises an upper saddle and a lower saddle, both saddles
having supporting faces the form of which is complementary to
that of the external surface of the pipe, the lower saddle
being articulated to the upper saddle, the lower saddle being
firmly fixed to a tilting lever able to press an upper part of
the pipe portion in order to cause the lower saddle to tilt
from an open position to a closed position, in which both
saddles press the pipe, the lever and the lower saddle being
able to tilt thanks to the lever effect generated when the
upper saddle and the upper surface of the pipe get closer.
In one embodiment, the tilting lever is out-of-line from
the assembly formed by the upper and lower saddles, in the
direction of the rotation axis.
In one embodiment, the length of the tilting lever is
superior or equal to the eighth of the pipe circumference.
In one embodiment, the length of the tilting lever is
inferior or equal to the quarter of the pipe circumference.
In one embodiment, the tilting lever has an incurved
profile.
In one embodiment, the tilting lever is incurved with a
curvature radius which is slightly, for example at least
0.5 mm, shorter than the pipe diameter.
In one embodiment, the assembly for a branch plug
comprises retaining means for retaining the lower saddle on
the upper saddle in order to carry out a removable junction
fixation of both saddles.
In one embodiment, the retaining means are snapping means.
In one embodiment, the retaining means comprise a toothed
shaft firmly fixed to the lower saddle and able to cooperate
with a passage hole in the upper saddle.
In one embodiment, the retaining means comprise a toothed
shaft firmly fixed to the lower saddle and able to cooperate
with a portion of a free edge of the upper saddle.
In one embodiment, the retaining means are doubled.
In one embodiment, the tilting lever is fixed in a
removable manner to the lower saddle, for example by a
snapping action.
In one embodiment, the assembly for a branch plug
comprises two tilting levers, arranged on both sides of the
lower saddle.
The invention also relates to a branch plug comprising a
barrel, a derivation pipe positioned on the barrel, and
provided with an assembly for a branch plug such as defined
above.
The invention will appear more clearly from the following
description by referring to the annexed figures in which:
- Figs, la and lb represent a branch plug according to the
invention, respectively in an open position and in a closed
position;
- Figs. 2a and 2b represent two branch plugs, respectively
provided with two embodiment variants of the invention;
- Fig. 3 represents an embodiment variant of the
invention;
- Fig. 4 represents a perspective view of a branch plug
according to the invention, in a closed position on a pipe;
- Fig. 5 represents the branch plug in Fig. 4 in an open
position.
Figs, la and lb show a branch plug 10 comprising an upper
or main saddle 12 and a lower or fixation saddle 22.
The main saddle 12 has a support surface 14 having a
substantially semi-cylindrical form and a circular section, an
extension axis 16, a holding edge 18 and a free edge 20. The
holding edge 18 and the free edge 20 are arranged on both
sides of the support surface 14 and extend in the direction of
the extension axis 16. A barrel 2 extends substantially
perpendicularly to the extension axis 16 and comprises an
internal passage opening onto the support surface 14,
substantially perpendicularly to this latter. Said internal
passage communicates with a derivation pipe 4 intended to be
connected to a new branch point.
The fixation saddle 22 has a support surface 24 and an
external surface 25 with a substantially semi-cylindrical form
and a circular section, an extension axis 26, a holding edge
28 and a free edge 20. The support surface 24 of the lower
saddle is substantially complementary to the support surface
14 of the upper saddle 12. The holding edge 28 and the free
edge 30 are arranged on both sides of the support surface 24
and the external surface 25. They extend substantially in the
direction of the extension axis 26.
The lower and upper saddles are connected to one another
near their holding edge in such a manner that the lower saddle
22 can easily pivot relatively to the upper saddle 12 around
an axis substantially parallel to the extension axis 16. In
the example, both saddles are articulated so as to rotate
around a rotation axis 32, for example by means of a cap-type
articulation. Of course, any other means for an easy rotation
of the lower saddle can be used instead, as for example a
semi-rigid liaison or a flexible liaison.
In the example, the rotation axis 32 is so arranged that
the median plane separating both hemispherical saddles is
substantially perpendicular to the axis of the barrel 2. In
other words, when the branch plug is fixed to a pipe (cf.
Fig. lb) , the angle between the radii respectively coinciding
with the rotation axis 32 and the axis of the barrel 2 is
substantially equal to 90°. In this configuration, when the
branch plug is correctly positioned, the axis of the barrel 2
is substantially vertical, and, preferably, the horizontal
plane containing the rotation axis 32 also contains the axis
where the free edges of both saddles meets.
Near the articulation axis 32, a tilting lever 34 is
arranged on the lower saddle while being linked to it without
being able to rotate. This lever is out-of-line from the
assembly formed by both saddles in the direction of the
articulation axis 32, and forms a projection in the direction
of the interior of the assembly formed by both saddles when
these are in an open position, such as represented in Fig. la.
Fig. la shows the first installation phase for the branch
plug: this one is progressively lowered to the pipe 1, the
lower saddle being free and hanging. According to the
invention, during its progression, the tilting lever comes to
press the upper part of a portion of the main pipe 1, in order
to drive in rotation the lower saddle when the device 10 is
going down. As shown in Fig. la, when an operator helps the
device 10 to go down to the main pipe, while maintaining the
upper saddle 12 substantially in the direction of the pipe
axis, the tilting lever 34 comes in contact with the upper
part of the pipe 1. If the device is still going down (under
the action of the gravity alone or by exerting an effort), the
lever causes then the lower saddle 22 to rotate to its closed
position represented in Fig. lb.
Retaining means 36 for the lower saddle 22 are provided on
the free edges 20, 30 of both saddles 12, 22, these means
enabling a temporary fixation of both free edges, and thus of
the lower saddle to the upper saddle. These retaining means
are for example snapping means. In the example in Figs, 1a and
1b, the retaining means 36 comprise a toothed shaft 361
arranged on the lower saddle and a passage hole 362 for said
shaft in the upper saddle. The passage hole 362 is conformed
so as to facilitate the passage of the toothed shaft 361 in
the direction of closing the branch plug 10 and to surely
maintain this closed position, while carrying out a fixation
that can be removed by an operator. Fig. 3 shows another
embodiment variant of the retaining means 36, in which a
toothed shaft 363 is conformed so as to be able to directly
cooperate with a portion of the free edge 20 of the upper
saddle, without using the passage hole. In that case, the free
edge 20 has advantageously a beveled form (such as notably
represented in Fig. 3), in order to facilitate the passage of
the toothed shaft in the closing direction. Whatever their
forms be, the retaining means 36 can be doubled (for example:
two shafts 361 cooperating respectively with two passage holes
362) .
As described above, a lower saddle according to the
invention is automatically installed and firmly fixed to the
upper saddle, also in an automatic manner, only under the
tilting action of the lever 34. Thus, only one operator is
able to install a branch plug from the upper part of a pit, in
a simple manner and without using any tool.
The form and the dimension of the lever 34 is adapted to
its function: notably, its length, which depends on the
diameter of the pipe considered, must be sufficient to press
the upper part of the pipe when the branch plug is relatively
close to the vertical plane containing the axis of the pipe. A
length superior or equal to about one eighth of the
circumference of the pipe considered is well adapted to this
requirement. Besides, the length of the tilting lever 34 must
enable to have a sufficient arm lever effect for easily
tilting the lower saddle with a reasonable effort by the
operator. However, it does not seem useful that the length of
the tilting lever be superior to the quarter of the
circumference of the pipe considered. Moreover, as shown in
Fig. 5, its form can be incurved, with a radius adapted to the
external surface of the pipe 1 in order to have a maximal
contact surface between the lever 34 and the pipe. In a
variant, it is advantageous that the tilting lever has a
slight tightening effect. To that end, it is important to make
sure that the lever profile is slightly closer to the pipe
than the profile of the upper saddle. For example, if the
lever has an incurved form, the desired tightening effect will
be obtained when the internal diameter is about 1 millimeter
shorter than the diameter of the pipe considered.
According to the invention, the lower saddle 22 can be
provided with only one tilting lever or with several tilting
levers 34. As shown in the figures 2a, 4 and 5, two tilting
levers can be indeed provided, which will enable a better
distribution of the charge on the pipe, and which will also
avoid the assembly to be over-mounted when the operator
transmits his/her effort via the barrel.
Once the lower saddle is fixed thanks to the retaining
means 36, the • operator can, as the case may be, either
directly weld the branch plug to the pipe or take advantage of
the temporary fixation for fixing it in a more safely manner
(for example by means of screws and bolts 38 through holes 40
in the free edges of both saddles, as shown in Figs. 2a and
2b), before continuing the installation of the branch plug.
In a variant represented in Fig. 3, the device is fixed in
a removable manner to the lower saddle 22, this one can thus
be removed once the plug is welded, and reused.
The device according to the invention is thus advantageous
in that it enables to install a branch plug, without any
conventional tools, from the upper part of a pit. Its
manufacturing cost is low, and in its removable version, it is
moreover reusable. The invention is simple and quick to
implement, with a reduced operation time for the operator.
WE CLAIM:
1. Assembly for a branch plug (10) of a derivation on a
portion of a fluid transport pipe (1), notably a gas transport
pipe, characterized in that it comprises an upper saddle (12)
and a lower saddle (22), both saddles having supporting faces
(14, 24) the form of which is complementary to that of the
external surface of the pipe (1) , the lower saddle (22) being
articulated (32) to the upper saddle (12), the lower saddle
(22) being firmly fixed to a tilting lever (34) able to press
a upper part of the portion of the pipe (1) in order to cause
the lower saddle (22) to tilt from an open position to a
closed position, in which both saddles press the pipe (1), the
lever (34) and the lower saddle (22) being able to tilt thanks
to the lever effect generated when the upper saddle (12) and
the upper surface of the pipe (1) get closer.
2. Assembly for a branch plug according to claim 1, wherein
the tilting lever (34) is out-of-line from the assembly formed
by the upper and lower saddles, in the direction of the
rotation axis (32) .
3. Assembly for a branch plug according to claim 1 or 2,
wherein the length of the tilting lever (34) is superior or
equal to the eighth of the circumference of the pipe (1).
4. Assembly for a branch plug according to claim 1, 2 or 3,
wherein the length of the tilting lever (34) is inferior or
equal to the quarter of the circumference of the pipe (1).
5. Assembly for a branch plug according to any one of the
claims 1 to 4, wherein the tilting lever (34) has an incurved
profile.
6. Assembly for a branch plug according to claim 5, wherein
the tilting lever (34) is incurved with a curvature radius
which is slightly, for example at least 0.5 mm, shorter than
the diameter of the pipe (1).
7. Assembly for a branch plug (10)according to any one of the
claims 1 to 6, comprising retaining means (36) for retaining
the lower saddle (22) on the upper saddle (12) for carrying
out a removable junction fixation of both saddles (12, 22).
8. Assembly for a branch plug (10) according to claim 7,
wherein the retaining means are snapping means.
9. Assembly for a branch plug (10) according to claim 8,
wherein the retaining means (36) comprise a toothed shaft
(361) firmly fixed to the lower saddle (22) and able to
cooperate with a passage hole (362) in the upper saddle.
10. Assembly for a branch plug (10) according to claim 8,
wherein the retaining means (36) comprise a toothed shaft
(363) firmly fixed to the lower saddle (22) and able to
cooperate with a portion of a free edge (20) of the upper
saddle (12).
11. Assembly for a branch plug (10) according to any one of
the claims 7 to 10, wherein the retaining means are doubled.
12. Assembly for a branch plug (10) according to any one of
the claims 1 to 11, wherein the tilting lever is fixed in a
removable manner to the lower saddle (22), for example by a
snapping action.
13. Assembly for a branch plug (10) according to any one of
the preceding claims, comprising two tilting levers (24),
arranged on both sides of the lower saddle (22).
14. Branch plug (10) comprising a barrel (2), a derivation
pipe (4) positioned on the barrel (2), and provided with a
branch plug assembly according to 1 to 13.

The invention relates an assembly for a branch plug (10)
of a derivation on a portion of a fluid transport pipe (1),
notably a gas transport pipe, characterized in that it
comprises an upper saddle (12) and a lower saddle (22), both
saddles having supporting faces (14, 24) the form of which is
complementary to that of the external surface of the pipe (1),
the lower saddle (22) being articulated (32) to the upper
saddle (12), the lower saddle (22) being firmly fixed to a
tilting lever (34) able to press a upper part of the portion
of the pipe (1) in order to cause the lower saddle (22) to
tilt from an open position to a closed position, in which both
saddles press the pipe (1), the lever (34) and the lower
saddle (22) being able to tilt thanks to the lever effect
generated when the upper saddle (12) and the upper surface of
the pipe (1) get closer.