An Underwater Installation and Flowline Connecting Apparatus for use at the Underwater Installation

摘要

1,161,616. Pipe joints; Coupling pipes to underwater installations. SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ N.V. 28 Dec., 1966 [30 Dec., 1965], No. 57935/66. Headings F2G and F2P. The invention relates to remotely coupling an underwater pipeline to an underwater well head structure 43 from a vessel 32. A structure assembly 65 mounting a well head connector 60 of one or more rigid conduits 55 and 56 presenting horizontally-directed end portions 57, 58, which has been lowered along guide lines 48 into engagement with the well head, guide tubes 66 co-operating with locating columns 46 of the well head structure, is provided with a combined cable guide structure and alignment anchoring assembly 70 is similarly lowered on a running string 71 along guide lines until guide tubes 74 locate on pair of locating columns, an anchoring head 77 of the assembly 70 being detachably latched to a landing column 50 by radiallyacting dogs (318), Fig. 18 (not shown), actuated by an hydraulically-operated piston (317). An alignment tube 199 of the combined assembly then presents a flared mouth 203 at one end and a portion 201 for receiving a pipe line at the other end, said other end being axially aligned with but spaced from conduit end 57. A pipe-line pulling cable 79 which has previously been threaded through the cable guide structure and alignment assembly, is connected by a connector (83), Fig. 1A (not shown) of the type described in Specification 1,139,145, to the connecting head 85 of a pipeline 86 and the cable recovered at the vessel until the pipeline head is locked in the receiving end 201 of the alignment tube by spring urged dogs (234), Fig. 15 (not shown). The cable guide structure 91, Fig. 11, comprises an upper tube 97 connected to the running string and a lower elbow portion 257 which is normally-latched to the alignment tube by piston-operated radially-acting dogs 289 of an end connector 93. The structure is mounted on a subframe 99 which is connected to the main supporting structure 73 of the combined assembly 70. After locking of the pipeline head in the alignment tube, connector 93 is unlatched and a piston/cylinder unit 298 operated to axially disengage the cable-guide structure 91 from the alignment tube, Fig. 7 (not shown), such movement being permitted by horizontal slots 115 in the cable guide structure subfame 99. A further piston/cylinder 264 is then actuated to raise the cable guide structure vertically, Fig. 8 (not shown), thereby leaving the space between the end of conduit 57 and pipe line head 85 unimpeded by apparatus. The conduit end and pipe line head are then moved into mating engagement, Figs. 9 and 10 (not shown). Movement of the pipe line end to the left is achieved by movement of the alignment tube which is mounted on side runners (191, 193), Fig. 14 (not shown), of the anchor head support plate 185 and reciprocated by a pair of hydraulic piston/cylinder units (209). The conduit end 57 is moved to the right by an extendible unit (311), Fig. 16 (not shown). The hydraulic supply lines to the piston/cylinder units and latching devices are lead through a line 135, Fig. 12 (not shown) from the vessel 32, lines 141-145, having a detachable plug in connection to a connector head 149 mounted on the anchor head and alignment tube support structure. The other conduit 56 connected to the well-head may be similarly connected to another pipe line 88, Fig. 17 (not shown).