Brief Description of the Drawings
To understand the invention better, particular embodiments will now be described by way of nonlimiting examples with reference to the accompanying drawing in which:
FIG. 1 represents diagrammatically a connector of tubular pipes according to a first embodiment of the invention,
FIG. 2 is a diagrammatic view in section of a connecting device of a type that can be used in the connector of FIG. 1, in assembled position,
FIG. 3 is a view in section along III--III of FIG. 2,
FIGS. 4 and 5 are views similar to FIG. 2, showing the connecting device during two separation phases,
FIG. 6 is a view in the direction of arrow VI of FIG. 5 illustrating the separation of the segments of the nut,
FIG. 7 illustrates a connector of tubular pipes according to a second embodiment,
FIG. 8 illustrates a variant of this connector,
FIGS. 9 and 10 are views respectively in cross section and in elevation of another connector embodiment according to the invention,
FIG. 11 further illustrates another connector embodiment of tubular pipes.
Description of the Preferred Embodiment
FIG. 1 illustrates a connector of tubular pipes such as those used for the transport of hydrocarbons and with a vertical axis in the example illustrated.
The connector comprises two annular flanges 1 and 2 between which a quick disconnection under load should be able to be made, a plurality of connecting devices 3 described more in detail with reference to FIGS. 2 to 6 being distributed on said flanges 1 and 2. Each connecting device comprises a shaped rod 4, threaded in the example shown, which goes through flange 1 of the upper connector element and is fastened by a corresponding nut 5 to the flange of the other connector element. The connection is provided by locking of a sleeve 6 engaged around a tapped ring forming nut 7 of each connecting device against flange 2. A nut 8 screwed on a thread 9 of free end 10 sleeve 6 secures the sleeve of an annular plate 11 mounted coaxially around the upper connector element. A thrust cylinder 12 is provided to lift plate 11 while resting against flange 2. Advantageously several cylinders could be provided.
It is understood that an actuation of cylinder 12 causes a separation between flange 2 and plate 11 and therefore the movement of sleeves 6 of the various connecting devices as illustrated in FIGS. 2 to 6.
In these figures, the operating principle of a connecting device that can be used in the connector according to the invention has been illustrated.
These connecting devices are known in their principle. An application to the disconnection of a covering structure in an offshore drilling platform is, for example, described in the patent U.S. Pat. No. 4,082,468. In this document, it is a matter of being able to perform an easy disconnection by divers but not as in this invention a disconnection as quick as possible under heavy load.
The connecting device according to the invention comprises an annular ring 7, with an outside cylindrical surface, but which could be slightly conical, and which, in the example shown, consists of assembly of three equal complementary segments 7a, 7b, 7c.
On ring 7, in which the end of a threaded rod 2 is engaged here by screwing, a sleeve designated overall by 6 is engaged with an interference fit. This sleeve 6 comprises a lower part exhibiting a lower bearing surface 13 applied on the periphery of ring 7, and a part of free upper end 10 exhibiting, for example, a threaded outside section 9 and on which can be engaged a nut 8 (FIG. 1) holding sleeve 6 on a structural element to be separated from the structural element to which threaded rod 4 is fastened.
In the example illustrated with a threaded rod and a nut, there is provided a cylindrical pin 14 housed in grooves 15 and 16 of semicircular section of inside wall 13 of the sleeve and of the outside wall of segment 7c of the nut. This cylindrical pin is intended to facilitate the transmission of a locking torque to the nut after shrink-fitting thereon of the sleeve by application of a tool such as a wrench on the nut.
When, as illustrated in FIG. 5, a pull is exerted in the direction indicated by arrow T, there are performed an unshrinking and a movement of sleeve 6 in relation to nut 7 which remains solid with threaded rod 4. When the position illustrated in FIG. 5 is reached, the segments of nut 7 are no longer held on the inside of the recess of sleeve 6, which permits their separation as diagrammed by arrow S in FIG. 4 and a separation of nut 7 from rod 4 which, no longer being held, separates in the direction of arrow R illustrated in FIG. 4.
The connector illustrated in FIG. 7 differs from the one illustrated in FIG. 6 particularly by the fact that each of rings 17 of the connecting devices exhibits an outside surface stepped with a lower part of larger outside diameter 18 and an upper part of reduced outside diameter 19, a set-back 20 thus being made between the two parts. Shrink-fitted sleeve 21 exhibits an inside section shape suited to that of ring 17.
A shaped rod 22, here threaded, solid with a flange 23 is screwed into the ring, here a nut 17, on a part of its length, approximately up to set-back zone 20, while an upper shaped rod 24, here threaded, solid with a flange 25 is screwed into nut 17 until coming approximately opposite the end of rod 22. In this example also, nut 17 is made in three complementary segments. Sleeve 21 is made solid with an annular plate 26 by a nut 27 similar to nut 13 of the preceding embodiment. Also, nuts 28 and 29 make threaded rods 22 and 24 solid with flanges 23 and 25. As in the embodiment of FIG. 1, a seal 30 is provided between the two connector elements.
It is understood that by bringing together plate 26 of flange 25 under the effect of cylinder 12, sleeve 21 lifted by nut 27 slides in relation to nut 17 until its lower end comes into the set-back zone of the outside surface of the nut causing a separation of the segments that make up the nut.
This embodiment makes possible a quick disconnection under heavy load in the case where the load is highly deflected in relation to the longitudinal axis of the connection.
The embodiment of FIG. 8 differs from that of FIG. 7 by the fact that each threaded rod 22' and 24' no longer comprises a threading but a denticulation that is, a series of annular ridges or ribs, ring 17' being internally denticulated in a corresponding way. The tops and bottoms of the teeth are located in parallel planes orthogonal to the axis of the ring and rods.
Such a shaping in the form of denticulation can, of course, be used for rod 4 and ring 7 of the embodiment of FIG. 1. The term "serrations as used in the claims below is intended to cover both helical threads and annular denticulations.
In the embodiment of FIGS. 9 and 10, there is provided an annular element in the shape of a stirrup 31 connecting two flanges 32,33 opposite the assembled connector elements. In the example illustrated, the stirrup comprises two parts 34,35 articulated in relation to a part 36, a quick-separation connecting device according to the invention being placed between two opposite flanges 37,38 of parts 34,35. Thus, sleeve 39 is engaged on a nut 40, for example, having three segments inside of which is screwed a threaded rod 41 drawn by a nut 42 against flange 37. The separation of flanges 37,38 and therefore the opening of stirrup 31 and the separation of flanges 32,33 of the connector is assured by a cylinder 43 solid with sleeve 39 and whose rod 44 rests on threaded rod 41.
In the embodiment of FIG. 11, a single connecting device is provided whose tubular threaded rod 45 is one of the connected pipes, a nut 46 surrounded by a sleeve 47, being placed around rod 45 and the other pipe 48.
As shown, the upper pipe 48 has a peripheral shoulder 51, while the lower pipe 45 has a threaded periphery 52. The internal flange 53 of nut 46 bears against shoulder 51, while the threaded periphery 52 is engaged by mating internal threads on the nut.
Sleeve 47 comprises a flange 49 on which the rod of a cylinder 50 rests for disconnection.
The platform 54 which supports the body of the hydraulic cylinder may be connected to one of the pipes, directly or indirectly, as in FIG. 9. Other means for moving the sleeve could also used, in place of the cylinder shown.
According to the invention, particularly simple and reliable connectors can be made that can be separated under the effect of a force that is a great deal less than the load brought about by the tension of corresponding rods, for example 15 to 20 times less than this tension.
Thus, for example, with a threaded rod 2 or 22 of dimension M30 with a nut locking torque of 130 m.daN corresponding to a rod tension of 29 tons, an axial force of 1.7 tons suffices to perform the disconnection.
Although the invention has been described in connection with particular embodiments, it is quite obvious that it is in no way limited to them and that numerous variants and modification can be made to it without thereby going outside its scope or its spirit.