The present invention relates to a system for establishing a sealing connection between two axially impacting joint components of a pipe conduit, where the joint components are each provided with their respective mutually cooperating, radial impact surface and with their respective annular cavity disposed radially within, which extends to a an inner surface of each respective part and which jointly define a groove for the reception of an elastically yielding sealing ring, preferably metal sealing ring having a substantially wedge stump-shaped cross-section, an annular series of tension means being adapted to exert an axial prestressing force between the two axially impacting joint components via the sealing ring and the radial impact surfaces, where the tension means with associated tension portions are carried in a first joint component, while a stop equivalent to the tension portion is designed in a second joint component.

Present invention is a further development of a system as illustrated in NO 167 474. In said publication there is shown a system, in which a sealing ring is employed of elastically yielding metal (steel) . In practical constructions of the present invention it is appropriate, but not a necessity, that the sealing ring is

correspondingly as defined in said publication.

In known systems of the kind indicated by way of introduction the joint components, and especially the joint component which carries the tension means, are necessarily designed with a relatively large outer diameter, as a consequence of the use of axially moveable tension means, which extend more or less radially relative to the joint components. Generally, there is a need for joint components which occupy minimal space reckoned in the radial direction, but the need is particularly when the system is used at locations where available space is rather limited, especially internally in the pipe conduits or in similar conveyors.

According to the invention the objective first and foremost is a system in which the joint components, especially the tension means-carrying joint component, can be designed with a minimal radial dimension, but also preferably with a minimal axial dimension. The particular aim is to arrive at a solution where the tension portion of the tension means can be moved within a relatively constricted work zone. In other words the aim is a system having a particularly suitable tension means, which has a simple and solid construction and which in addition has a reliable and effective mode of operation. The invention is characterised in that the tension means is rotatably mounted about its longitudinal axis in the first joint member, the longitudinal axis extending in a radial plane through the joint members and being arranged radially outside the stop in the second joint member, and that the tension portion of the tension means is swingable from an inactive position radially outside the stop to an active, power-transferring position having a supporting abutment against the stop.

By employing according to the invention tension means which are pivotable about the longitudinal axis - instead of axially moveable tension means - one has the possibility of limiting the zone of movement of the tension means and thereby the extension of the joint

members both in a radial direction and in an axial direction. More specifically the tension portion of the tension means can be readjusted from the inactive to the active position within a limited work zone at the same time as the tension means can be designed with a compact construction having relatively small dimensions. This involves being able to readjust the tension portion of the tension means by means of a pivotal movement from an inactive position, in which the joint members can ^' be moved unhindered towards and away from each other, to an active position, in which the joint members are arranged in supporting abutment against each other, in readiness for the transfer of a prestressing force between the joint members. Furthermore, this involves that thereafter, when the joint members form a mutually supporting abutment in their active positions of engagement, the prestressing force can be transferred separately between the joint components almost without movement of or only with a minimal movement of the tension means relative to the joint members.

Another important effect which is achieved by the afore-mentioned characterising feature of the invention is that one can ensure that the loading from the tension means towards the second, inner joint component can occur mainly in the axial direction of the joint component and without or only with a minimal loading in the radial direction towards the second, lower joint component. In other words one has the possibility of transferring large axial loadings between the joint components within a relatively constricted radially extending zone by arranging the pivotal axis of the tension means relatively tightly up to cooperating impact surfaces of the joint components.

Present invention is further characterised in that the tension means, between two opposite end surfaces, is provided on the one side with the tension portion having an associated tension surface and on the diametrically opposite side is provided with a back surface, which

cooperates with an actuating means separately moveable in the first joint component, for example a slide valve, for readjusting the tension means between the inactive position and the active position for mutual locking together of the joint components.

By way of simple means and in a ready manner, by for example linear movement of the actuating means (the slide valve) and accompanying swinging of the tension means, it is consequently possible according to the invention to lock the tension means in the intended engagement position and thereby lock the joint components relative to each other. The joint components are thereby locked in a reliable manner relative to each other, independently of the prestressing force, and substantial mutual movement between the joint members both axially and radially can be avoided.

There is achieved by this a possibility to lock the joint components together separately immediately as they are pushed together into mutually supporting abutment, that is to say independently of and before effecting the transfer of the prestressing force between the joint components. By effecting the readjustment of the tension means independently of the prestressing force the prestressing means can be swung without hindrances in a ready manner in a relatively unloaded condition. By effecting thereafter the transfer of the prestressing force in the locked position of tension means, one has consequently minimal need for movement of the tension means during the transfer of the prestressing force, something which in turn involves being able to support the tension means in an effective manner during the transfer of the prestressing force itself.

By further inactivating the joint between the joint components, that is to say by retraction of the activating means itself, the locking engagement between the joint components is removed and this involves the tension means being able thereby to be pivoted unhindered back to the inactive starting position by quite simply pulling the

joint components in a direction away from each other.

The invention is further characterised in that the tension means is pivotably mounted in a housing member in the first joint component, that the tension means of the housing member is moveable with a limited movement in the first joint component in its axial direction, and that a power-actuating means, in the form of a wedge, which is insertable in a gap in the housing member, is adapted to transfer prestressing force against the tension means substantially in the radial direction of the tension means and via the tension portion of the tension means against the stop in the second joint component. In other words it is only the displacing movement of the wedge itself which produces movement in the tension means and in that the displacing movement takes place in a region between the back side surface of the tension means and the tension surface of the tension means, one obtains a favourable power transfer from the first joint component to the second joint component via the stop of the tension surface in the second joint component.

By receiving the tension means according to the invention pivotably mounted in a housing member in the first joint component and transferring the prestressing force from the power transfer means, via the wedge in said gap in the housing member, to the tension surface of the tension means, an effective support of the tension means can be simultaneously secured during the transfer of the prestressing force.

By combining the actuating means for adjustment of the tension means to and from the locking position with an actuating means for loading of the power transfer means (the wedge) , there can be secured by simple means a locking of the joint components by way of introduction and thereafter an axial transfer of the prestressing force between the joint components in separate, but if necessary in directly following operations. In addition the mechanism which is to actuate the tension means during its different functions, that is to say the locking function

and the power transfer function, can be simplified.

It is preferred that each power transferring tension surface coincides with or is substantially aligned with a plane through the pivotal axis of the tension means. By this one can ensure that the tension force which is exerted from the actuating means (the slides) towards respective tension means, in a direction substantially radially inwards towards the tension means, is transmitted mainly in an axial direction through the first, upper joint component and almost exclusively in an axial direction through the second, lower joint component, the resultant force being received in the said housing member in the first, upper joint component. This preferred solution also fulfills the need to produce as far as possible a compact construction having the least possible axial and radial dimensions.

Further features of the invention will be evident from the following description having regard to the accompanying drawings, in which: Fig. 1 shows two cooperating joint components, seen in side view, according to a first schematic embodiment.

Fig. 2 shows a plan view of the same as in Fig. 1, seen from above.

Fig. 3 shows a cross-section of a first joint component.

Fig. 4 shows a side view of a second joint component.

Fig. 5A-5C show in cross-section the coupling together of the joint components, illustrated in three successive coupling phases. Fig. 6 shows a perspective view of the tension means with associated parts in a mounted together condition.

Fig. 6A-6F show the components in Fig. 6, illustrated individually, with the tension means shown in Fig. 6E.

Fig. 7 shows the tension means in perspective from another visual angle than illustrated in fig. 6E.

Fig. 8 shows in perspective view a lid for covering the tension means and its cooperating parts.

Fig. 9 shows in perspective view an actuating means

in the form of a slide.

Fig. 10 shows in side view an alternative construction of a coupling together unit according to the invention. Fig. 11 shows in plan view, seen from above an upper end cover member of the coupling together unit according to Fig. 10.

Fig. 12 shows in plan view, seen from below a lower end cover member of the coupling together unit of Fig. 10. Fig. 13 shows the coupling together unit partly in side view and partly in section in a condition ready for use.

Fig. 14 and 15 show in side view and in front view respectively an actuating means in the form of a slide and an associated piston rod.

Fig. 16 and 17 show in vertical section and in plan view respectively, seen from above a packing sleeve for the piston rod as shown in Fig. 14 and 15.

Fig. 18 shows the end cover member according to fig. 11 seen from the under side.

Fig. 19 and 20 show cross-sections of the end cover member illustrated along lines 19-19 and 20-20 respectively in Fig. 18.

Fig. 21 shows a side view of the end cover member illustrated along a transverse section line 101c.

Fig. 22 shows a packing sleeve in a part of the end cover member according to Fig. 18.

Fig. 23 shows a vertical section of an upper joint component. Fig. 24 shows from above a plan view of the upper joint component.

Fig. 25 shows in plan view the upper joint component, correspondingly as shown in Fig. 25, with certain cavities shown drawn in broken lines. Fig. 26 shows the upper joint component, illustrated partly in side view and partly in vertical section.

Fig. 27 and 28 show a side view and a rear side view respectively of a lid for covering a tension means and its

cooperating parts.

Fig. 29 and 30 show a housing member seen in side view and rear side view respectively.

Fig. 31 and 32 show a side piece for the housing member seen in rear side view and side view respectively. Fig. 33 shows an end view of a wedge stop. Fig. 34 and 35 show an end view and a side view respectively of a wedge which forms the power transferring prestressing means of the tension means. Fig. 36 and 37 show respectively a side view and a plan view seen from above of a tension means according to the invention.

Fig. 38 shows in a part of Fig. 13 details in the slide and its associated tension means. Fig. 39 and 40 show the second, lower joint component illustrated partly in side view and partly in vertical section and seen from below in plan view respectively.

In the accompanying drawings, see more particularly Fig. 1, there are in a first schematic embodiment illustrated in Fig. 1-9 two cooperating joint components 10 and 11, which are shown separately, that is to say without connection to adjacent conduit pieces and without surrounding well pipes. In practice, however, each of the joint components will be permanently connected at a corresponding end to an associated, aligned pipe piece or other corresponding connection piece, which forms a part of a gas/oil/ medium conduit, which in turn will be receivable in a well pipe. For the sake of clarity end covers are omitted in the construction according to Fig. 1-9, opposite end covers only being illustrated in the embodiment of Fig. 10-40.

The joint components 10,11 are more especially applicable in connection with offshore well boring operations and in connection with gas or oil conduits and are particularly designed in order to function under high medium pressures with extremely high pressures occurring occasionally.

In Fig. 3 and 5C the joint components 10,11 are shown

in detail in axially coupled together condition for use. A first, socket-forming joint component 10 (see Fig. 5A) forms an axial support abutment against a second, insertion part-forming joint component 11, via their respective mutually cooperating, radially extending impact surfaces 10a and 11a respectively. In Fig. 3 and 5C the insertion component 11 is shown in place in a fully pushed in, locked position in the socket component 10.

The sealing off itself between the joint components 10,11 is special on account of the coupling unit being designed so as to be able to compensate for extremely high pressures occurring occasionally. Radially within the impact surface 10a of the joint component 10 (see fig. 5A) a bevelled cavity 12 is formed, which opens inwardly towards radially innermost surface 10b of the joint component 10, while radially within the impact surface 11a of the joint component 11 there is formed an equivalent, bevelled cavity 13, which opens inwardly towards radially innermost surface lib of the joint component 11. Between the cavities 12 and 13 there is received an elastically yielding metal sealing ring 14 (see Fig. 5B and 5C) having a trapezoidal cross-section. The joint components 10,11 are consequently mutually sealed off with a single sealing ring 14, which is arranged tightly up to the impact surfaces 10a,11a.

In order to secure sealing off via the elastically yielding metal sealing ring there is a need for a prestressing force which is exerted via the sealing ring. The prestressing force is limited to a specific size (for example 20 ton) in a manner known per se, as is illustrated in NO 167 474, by the mutual abutment of the joint components 10,11 via the impact surfaces 10a,lla.

The sealing ring 14 is provided with opposite clamp surfaces 14a and 14b, which form supporting abutments against equivalent sliding surfaces 12a and 13a of the cavities 12,13. The clamping force, which is exerted against the sealing ring 14 via the clamp surfaces 14a and 14b and which to a corresponding degree can deform the

sealing ring 14, is determined by the supporting abutment between the impact surfaces 10a, 11a.

The radial outer narrow end surface 14c of the sealing ring is shown at a certain radial distance from equivalent end surface sections 12b and 13b of the cavities 12,13, so that in the bottom of the cavities 12,13 there is formed a chamber, in which the sealing ring can be received (in the yielding condition of the material) on the occurrence of exceptionally high medium pressures in the bore internally in the joint components

10,11. The sealing ring can thereby be allowed to "yield" as required in a direction radially outwards. Such a solution is shown further in NO 167 474.

In order to ensure a uniformly distributed surface pressure on the sealing ring 14 having said prestressing force, it is of great importance that the tightening together of the joint components 10,11 happens in a controlled, accurate manner. It is furthermore of great importance that the coupling together unit is constructed as far as possible compactly, so that it occupies as little as possible space both axially and radially in the surrounding pipe conduit. As is evident from Fig. 2 a first joint component 10 is provided with four pairs of diametrically opposing tension means (dogs) 15 directed radially inwards, with associated tension portion 16 (see Fig. 3) having active tension surface 17. The tension means 15 are distributed having 36° angle intermediate spacings, while two diametrically opposing intermediate spacings 18,19, which form cavities in the coupling unit itself, are without tension means.

As is evident from Fig. 4 the remaining, second (lower) joint component 11 is provided with a cavity 20 opening radially outwards having a stop 21, with associated radially extending support surface 22, for tension surface 17 of the tension means.

In Fig. 5A tension portion 16 of the tension means 15 is shown in a passive, retracted condition of the first joint component 10, so that the second, insert portion-

forming joint component 11 can be freely pushed inwardly into and outwardly from the socket-forming joint component 10.

In Fig. 5B the joint components 10,11 are pushed axially together (the sealing ring 14 is indicated by broken lines in Fig. 5B) . Thereafter the tension means 15 is rotated about a longitudinal axis 15a, as shown in Fig. 6E and 7, so that the tension portion 16 of the tension means 15 is pivoted inwardly into the cavity 20 and so that the tension surface 17 forms an abutment against the support surface 22 of the stop 21 of the joint component 11. The rotation of the tension means 15 is achieved by a slide 23 being pushed vertically downwards along a backside surface 34 of the tension means 15, that is to say on the opposite side of the tension means relative to the tension portion 16. As is shown in Fig. 9 the slide is provided with an obliquely bevelled, rounded guide edge 23a at its lower, inner end.

In the position as shown in Fig. 5C, that is to say after the tension means 15 has assumed its locked position, as shown in Fig. 5B, a considerable clamping force A is exerted from the tension means 15 and further through the joint components 10,11 across the sealing ring 14 until supporting abutment is obtained between the impact surfaces 10a,11a. This clamping force is exerted towards the tension means 15 by the slide 23 being pushed downwards and pressing a wedge 24 radially- inwards into a gap between the tension means 15 and the lower end of the joint component 10. With reference to Fig. 6 a practical construction of the tension means 15 and cooperating parts is shown for readjusting and locking the tension means relative to the joint component 11 and for the exertion of a clamping force between the joint components 10,11 via the tension portion 16 of the tension means 15 and the stop 21 of the joint component 11.

The tension means 15 (see Fig. 6E and 7) is composed of steel in a solid construction. As shown in Fig. 6 the

tension means 15 is received rotatably mounted in a housing component 25, which comprises two opposing side pieces 26,27 (see Fig. 6A and 6B) and an intermediate top member 28 (Fig. 6C) together with an intermediate bottom member 29 (Fig. 6D) . In a first construction, as illustrated herein, the members 26-29 together with the tension means 15 are mounted together in loose connection with one another and held in place relative to one another by means of a cavity 38 (Fig. 3) adapted for this purpose in the joint component 10. By this the tension means in an unloaded starting position has the possibility of being able to be turned relatively unhindered between members 26-29 of the housing component 25, from and to the locking position of the tension means as required. On the other hand when the tension means 15 has assumed its locking position, it can be firmly clamped between certain of the housing members (top member 28 and bottom member 29) under the power loading of the tension means. The tension means 15 is rotatably mounted with a rotary fit and the power loading is transmitted from the tension means 15 to the housing component 25 via pivot bearings 26a,28a and 27a,28a.

In a second, preferred construction, which will be described further along in the description (see Fig. 29- 30) the members are connected to each other by way of fastening means in the form of guide surfaces and associated guide pins into a coherent housing component. In two opposite end surfaces 15b,15c of the tension means 15 there are formed bearing-forming cavities 28a, while the side pieces 26,27 are provided with equivalent bearing-forming tenons 26a,27a which project laterally inwards into the cavities 28a (Fig. 6) . The tension means 15 is provided on diametrically opposing side portions with cylindrically curved surfaces, that is to say a first narrow surface 30a and a second broad surface 30b. The narrow surface 30a cooperates with and forms a supporting abutment against a broad cylindrically curved surface 31 of the top member 28, while the broad surface 30b

cooperates with and forms a supporting abutment against a broad cylindrically curved surface 32 of the bottom member 29 and (respectively in Fig. 8 and 9) and against a broad cylindrically curved surface 33 (Fig. 4) of the cavity 20 of the joint component 11. On the one side between the surfaces 30,31 the tension means 15 is provided with the back surface 34 which forms a sliding and actuating surface for the slide 23. On the other side between the surfaces 30,31 the tension means 15 is provided with a first broad surface 36, which is concavely angled (Fig. 6) relatively to a second narrow surface which forms tension surface 17 of the tension portion 16. The tension portion 16 emerges consequently as a projection relative to the surface 36. The wedge 24 is, as illustrated in Fig. 3, shown introduced into a gap 35 between the bottom member 29 and the joint component 10.

The tension means 15 with associated housing component 25 (with individual members 26-29) together with the wedge 24 are in the form of separate components which are pushed into an equivalent cavity 38 in the joint component 10. Provision is made for a certain fit between the housing component 25 and the cavity 38. This is done inter alia in order to ensure a ready and unhindered rotation of the tension means from the position shown in Fig. 5A to that shown in Fig. 5B, that is to say in a phase where the tension means is without power stress or is only exposed to minimal power stress. In other words the tension means 15 is already adjusted into the active (locking) position before the prestressing force is supplied via the housing component 25 to the tension means 15.

The cavity 38 (Fig. 1) is provided along the top and the sides with guide surfaces 38a,38b,38c, which extend mutually parallel and at right angles to a longitudinal plane through the joint components 10,11, that is to say parallel to the equivalent outer top surface and outer side surfaces of the housing component 25. Along the

of fastening holes lOld are shown for fastening bolts for fixing the cover halves 101a and 101b to the joint component 10' .

In Fig. 23 the joint component 10' is shown in cross- section and in Fig. 24 in plan view, seen from above, illustrated without associated coupling members. In Fig. 25 the cylinder bores 112-and an adjacent cavity 38' for the coupling members are indicated in broken lines, while said cavity 38' is shown sideways in Fig. 26. In Fig. 27 and 28 a side view and a back side view are shown of a cover 41' which covers the cavity 38' and which with its obliquely extending back side surface 141a forms in a projection 141b a support surface for the slide 23' , so that the slide 23' can be moved in an accurately controlled manner relative to a tension means 15' together with an associated wedge 24' . The cover 41' is provided with a series of screw holes 141c for fastening the cover 41' to the outer side of the joint component 10' for accurate positioning of the cover and also for effective support of the cover during the exercise of tension force between the slide 23' and the wedge/tension means 24' .

In Fig. 29 and 30 a housing member 25' is shown in side view and back side view respectively with the tension means 15' illustrated in its locking position. The housing member 25' has two side pieces 26' ,27' which are mutually connected above with an intermediate top member 28' by means of first fastening screws 28a', the top member 28' being connected to the joint component 10' by means of second fastening screws 28b' . Below the side pieces 26' ,27' are mutually connected to an intermediate, separate bottom member 128 by means of first fastening screws 128a, the bottom member 128 being connected to the joint component 10' by means of second fastening screws 128b. A bearing-forming pin 26a' projects, as shown in fig. 31 and 32, laterally inwards from the side piece 26' so as to be receivable in an equivalent cavity 115a in the tension means 15' .

In Fig. 32 there are shown in the pin 26a' fastening

133a of the joint component 11' (see Fig. 39) . The surface portion 133a continues obliquely outwards and downwards with a concavely curved transition portion 133b, which is adapted to a part-cylindrical support surface 30b' on one side of the tension means 15' (see Fig. 29), which corresponds to the support surface 30b of the construction of Fig. 1-9. On the opposite side the tension means 15' is provided with a part-cylindrical support surface 30a' which can form a sliding abutment against a part- cylindrical surface 31' on the top member 28' . The support surface 30a' has a significantly larger surface area than the relatively narrow support surface 30a which is illustrated in the construction of Fig. 1-9.

The tension means 15' extends on the back side, from the part-cylindrical support surface 30b' , having a slightly convexly curved support surface 115d in order to ensure as far as possible a uniform sliding of the slide 23' and as far as possible an equivalently uniform turning of the tension means 15', the slide 23' being led along the support surface 115d of the tension means 15' between the position which is illustrated in broken lines and the position which is illustrated in full lines in Fig. 38. In Fig. 39 there is illustrated a side view of the one half of the joint component 11' and a vertical section of the other half of the joint component 11', while in Fig. 40 the joint component 11' is illustrated seen from the underside. Compared with the illustrations in Fig. 11 and 13 it will be evident that concave cavities Ilia are formed on opposite sides of the joint component 11' which are flush with the cavity 104 and the bore/cavity 105b of the joint component 10' . Provision is made for the cylindrical surface 133a of the joint component 11', which forms the stop for the end edge surface 116a of the tension means 15', to be arranged at a relatively short distance from the bore 103b that is to say substantially on line with the radially outermost portion 13b' of a metal sealing groove 13', so that the prestressing force which is transferred between the joint components 10' ,11'

is transferred in the joint component 11' substantially axially from a lower radially extending stop surface 22' to an upper radially extending support surface 11a' . By this an effective side support is achieved for end edge surface 116a of the tension means 15' against cylindrical surface 133a of the joint component 11' and at the same time an effective centering of the joint component 11' between the four pairs of tension means 15' . By employing a common pressure medium on all the tension means 15' a self-adjusting local loading of the joint component 11' can be ensured relative to the joint component 10' with a total loading adapted for this purpose radially and axially of the joint components 10' ,11'.