VALVE

Abstract: Valve apparatus, in particular a rotatable valve comprising an upper part (10) and a lower part (6) which are demountably attached to each other. The valve's lower part (6) is mainly U-formed with sealing surfaces (17, 18) arranged on the outwardly facing side faces, which sealing surfaces, in the case of closed valve bear against at least one valve seat on the valve housing's inlet and/or outlet end, and upper part's (10) external face is designed for totally or partly supporting bearing against lower part's (6) internal face and comprising a passage (34) designed to accommodate equipment, for example controlling or metering instruments in the upper part (10) can, in the case of closed valve, be lifted out of the valve housing (1) for maintenance.

Description: VALVE TECNICAL FIELD This invention concerns a device associated with a valve, in particular a rotatable valve comprising an upper part and a lower part which are detachably joined to each other. BACKGROUND ART Valves of the kind mentioned above can be made sufficiently large and robust in order to be mounted onto pipelines which transport hydrocarbons, particularly subsea pipelines, but the invention can also be exploited in other environments and in smaller dimensions. In the Norwegian patent application no. 860923 a ball valve is disclosed which is intended for connection with a pipeline system which conveys gas and/or oil at considerable sea depths. The valve can be demounted in a submerged state for instance for inspection or repair. Replacement of the internal vital parts can take place without any kind of extra cover and without the fluid in the pipeline leaking out during demounting, or without water from the surrounding environment being able to penetrate into the pipeline. This is achieved in that the rotatable member of the known valve comprises an upper part and a lower part. The upper part, which can be demounted from the valve housing, comprises, amongst other parts, the main packings of the valve. The lower part contains two displaceable sleeves which, when the valve can be demounted from the valve housing, comprises, amongst other parts, the main packings two displaceable sleeves which, when the valve is open, are displaced outwards to engage with bearings in the valve housing thereby forming a leakproof, continuous fluid passageway. In pipeline systems there is often a need for devices which can regulate the fluid flow and likewise there is a need for the mounting of metering equipment for instance for volumetric metering of fluid flows. Apparatus of the above-mentioned kind which are placed in a fluid flow, are subjected to considerable wear and tear and demand relatively frequent, periodical maintenance. It is desirable that maintenance can be performed quickly and that it should not be necessary to depressurize the pipeline. It is also desirable that medium from the pipeline will not leak out into the surrounding environment when maintenance takes place. DISCLOSURE OF INVENTION This is achieved by a valve according to the present invention which is characterized in that the lower part of the rotatable member is predominantly U-formed with sealing surfaces arranged on the outwardly facing side-faces, which sealing surfaces are, in the case of closed valve, engaged with the valve housing's valve seats on respectively the inlet and/or outlet end, in that the upper part's external surface is designed for totally or partly resting support against the lower part's internal surface and comprises a through-flow passage (23) intended for accommodating controlling or metering equipment, in that the upper part, in the case of closed valve, can be withdrawn from the valve housing for maintenance. BRIEF DECRIPTION OF DRAWINGS The invention will be more closely described in the following, making reference to the accompanying drawings where: Fig. 1 shows a vertical section through a valve according to the invention when this is in an open position or adjustable position, Fig. 2 shows a horizontal section through the valve shown in fig. 1, Fig. 3 shows a vertical section through the valve as -in fig. 1, but with the valve in closed position, Fig. 4 shows a vertical section through upper part and components attached to this, after they have been lifted out of the valve chamber in connection with a maintenance operation, Fig. 5 shows a horizontal outline of upper part and associated components which are shown in fig. 4, Fig. 6 shows a horizontal outline of the valve housing and lower part after the upper part has been lifted out, Fig. 7 shows a horizontal section through the valve housing and lower part which keeps the valve closed. MODES FOR CARRYING OUT THE INVENTION The constructive design of the valve will be described in detail with reference to the figures 1-3. The valve comprises a valve housing 1 with a cover 2 which encompasses the upper parts of the valve. The cover is secured to the valve housing by means of locking segments 38. The valve housing comprises further an inlet flange 3 and an outlet flange 4 which connect to a not shown pipeline • in a known manner. A duct for the fluid flow extends through the valve. In a practical embodiment there are supporting ribs 37 arranged on the lower side of the valve housing 1. On the under side of the valve housing 1, an internal bonnet 24 is placed between the valve housing 1 and the cover 2. • The rotatable component of the valve includes a U-shaped lower part 6 which by way of a journal 7 arranged on lower side is pivotally mounted in a bearing 8 arranged i lower part of the valve housing 1. An upper part 10 is designed to be supportably placed against the internal portion of the lower part 6. In order to achieve a firm and stable support between upper and lower part, lower part 6 comprises a rig 5, which engages with a groove 9 (fig. 5) in upper part 10. Upper part 10 comprises a through-going passage 34. In the area of respectively the passage's 34 inlet and outlet, the upper part 10 is provided with sealing elements 11, 12, which in the shown embodiment are bolted to upper part 10. The sealing elements comprise conical sealing surfaces 13, 14 which engage with correspondingly designed valve seats 15, 16 on the valve housing 1. Lower part 6 comprises correspondingly designed spherical sealing surfaces 17, 18 which with rotatable member in operating position, as most clearly shown in fig. 2, face perpendicularly in relation to upper part's sealing surfaces 13, 14. The rotating member's turn shaft 25 is pivotally mounted in a check bearing 23 in the internal bonnet 24. The valve's rotatable member can rotate from an open position as shown in fig. 1, where the upper part's sealing faces bear against the valve seats 15, 16, to a closed position as shown in fig. 3 where the lower part's sealing faces bear against the valve seats 15, 16 by rotating the whole rotating member 90 . When the valve is in a closed position the lower part stops the fluid flow through the valve at both the inlet end and the outlet end. For rotation of the rotating member, a hydraulic actuator 21 which acts on a turn shaft 22 is arranged. The turn shaft 22 is rigidly connected with the rotating member's turn shaft 25. The upper portion of the turn shaft 22 comprises splines 25 which engage with the hydraulic actuator 21. Upper part 10 is designed to be able to receive various types of controlling or metering instruments. The object of such equipment can be: - regulation of flow velocity recording of flow velocity - measuring of temperature - measuring of pressure volumetric metering of fluid flow As an example of such equipment, in the shown embodiment which is most clearly disclosed in figure 3, a controlling mechanism 26 is arranged in the fluid flow passage 34 for regulation of the fluid flow. In the shown example, the regulating device 26 comprises rotatable discs 27 which can be displaced radially in relation to each other in order to close/open the fluid flow passage 34. In the case of large drop in pressure across the valve two regulating devices 26 can be used as indicated in fig. 2. Rotation of the rotatable valve discs 27 is executed by means of a worm gear 28 which is directly connected to a gear ring on at least one of the valve discs 27. The worm gear is places in a bore 29 in the upper part 10 and is actuated by a connection motor 30. For a person skilled in the art it is evident that other equipment, for example metering or monitoring equipment, can also easily be accommodated in upper part 10. With reference to the figures 4-7, a closer description of the method for maintenance of the valve's vital parts and of equipment placed in upper part 10 will be provided. The first step will be to close the valve by 90 rotation of the rotating member so that the spherical sealing surfaces 17, 18 of the lower part bear against the valve seats 15, 16 of the valve housing 1. The valve will now be closed at both the upstream and downstream ends. The next step will be to equalize the pressure in the valve room with the ambient pressure before the cover 2 of the valve housing 1 is dismantled in that the locking segments 38 are released. Upper part 10 and associated equipment can now be lifted out of the valve housing 1 and be inspected/repaired. In a preferred embodiment, particularly when used in an underwater pipeline, upper part 10 and other components which are to undergo maintenance are attached to the underside of the cover 2. All components can now be lifted up to the surface via a hook 20 on the overside of the cover. The figures 4 and 5 show the unit which is lifted to the surface for maintenance, while the figures 6 and 7 show valve housing and lower part which remain where they are. The lower part 6 of the valve can preferably include an automatic locking mechanism which keeps it in a locked position when upper part 10 is lifted up (not shown) . When the upper part with equipment is mounted after overhauling, or possibly when a new corresponding unit is mounted, the groove 9 must enter above the rib 5. The unit will halt in lower position in that a bearing edge 31 on the overhauled unit encounters the support 32 of the lower part. Bearing surfaces 33 on upper part will fasten the upper part for sideways position in relation to lower part. Before the cover 2 is fastened in a known way and the valve is rotated into open position, the valve room should be flushed.

Claims: PATENT CLAIMS 1. Valve-apparatus, in particular a rotatable valve compri- sing an upper part (10) and a lower part (6) which, are demountably attached to each other, c h a r a c t e r ¬ i z e d in that lower part (6) is mainly U-formed with sealing faces (17, 18) arranged on the external side faces, which sealing faces, in the case of closed valve, bear against at least one valve seat on the valve housing's inlet and/or outlet end, and upper part's (10) external surface is designed for totally or partly supporting bearing against lower part's (6) internal surface and comprising a passage (34) intended for the accommodation of equipment, for example controlling or metering instruments in that upper part (10) , in the case of closed valve, can be lifted out of the valve housing (1) for maintenance. 2. Apparatus according to claim 1, c h a r a c t e r i ¬ z e d in that upper part's (10) sealing faces (13,14) in the valve's open position bear against the valve housing's (1) seats to form a closed fluid flow passage (34) . 3. Apparatus according to claim 1, c h a r a c t e r ! - z e d by the lower part (6) comprising a journal (7) arranged on the underside which is pivotally supported in a bearing (8) . 4. Apparatus according to claim 1, c h a r a c t e r i ¬ z e d in that upper part's (10) sealing surfaces comprise sealing members (11, 12) , with conically shaped sealing surfaces (13, 14) for engagement with correspondingly designed valve seats (15, 16) at the inlet and outlet of the passage (34) . 5. Apparatus according to claim 1, c h a r a c t e r i ¬ z e d by the lower part (6) comprising a rib (5) which fits into a groove (9) on upper part (10) in order to keep the parts (6, 10) in a fixed position in relation to each other. 6. Apparatus according to claim 1, c h a r a c t e r i ¬ z e d in that the revolvable member can be turned from open to closed position and vice versa via a rigidly connected turn shaft (22) which is pivotally mounted in a check bearing (23) in an internal bonnet (24) and comprises, in the upper free end, splines (25) which engage with a hydraulic actuator (21) . 7. Apparatus according to claim 1, c h a r a c t e r i ¬ z e d in that one or more controlling devices (26) are arranged in the passage of the upper part (10) for regulation of the fluid flow, each of which comprise rotatable discs (27) which can be displaced radially in relation to each other by means of a worm gear (28) which engages with a gear rim on at least one of the discs (26) of the valve. 8. Apparatus according to claim 6, c h a r a c t e r i - z e d in that the worm gear (28) is driven by a motor (30) placed in a bore (29) in upper part (10) .

Inventors: HORVEI KNUT V, HORVEI, KNUT, V.
Applicants: NORSKE STATS OLJESELSKAP, DEN NORSKE STATS OLJESELSKAP A.S
Application year: 1990
Main classification: F16K5
IPC codes: F16K3, F16K5, F16K49