GB1382693A - Method of connecting underwater installations - Google Patents

Abstract

1382693 Loading and unloading : bridge cranes SUBSEA EQUIPMENT ASSOCIATES Ltd 3 Aug 1972 [21 Oct 1971] 36310/72 Headings B8B and B8E An installation on a drilling ship or platform or other floating body has means to withdraw heavy loads from a storage space which permits assembly of different parts and means by which a derrick can lower the load down a well while guided and held against lateral displacement. A storage space between the main and upper decks 2, 3 of a drilling ship, Fig. 14, has vertical guides 14, Fig. 3, retractably mounted by frames 18 but holdable in operative position by stays or rams and vertically movable to be corimectible as by spigots to similar retractable guides 11 mounted on frames 13 in the well or connectible to guides 21 in the derrick 4. The derrick 4 is positioned vertically above a well of the ship and the crane 8, supported on a rollway 7, Fig. 3, can be moved in between by a motor 35, Fig. 5, driving a pinion 38 engaging a rack 39 the crab 34 can be moved across the crane by a pinion and rack 48, 49, Figs. 5, 6. Depending from the crab are two columns 54 having counterweighted retractable sheaths 56 provided with spaced ears 64 connectible by a support 63 to a load at the level of its centre of gravity. Aplatform 10, Figs. 3, 9, is movable over the well on a rollway 9 by a motor 69 through a rack-and-pinion drive 68, 71, and is lockable by devices 73. The platform has attachment points 79 so that a load can be secured by claws 81, Fig. 13, provided with a securing nut 83. A collar 25, Fig. 4, engages the load by pads 28 actuated by rams 26 which collar co-operates with the guides 11, 14, 21 during vertical movement to resist lateral forces. In use with the platform 10 over the well, Fig. 14, a load is brought from store by the crane and secured thereon. With the collar 25 fitted the load can be withdrawn on to the guides 21 of the derrick by its tackle 85 and the guides 14 can be retracted to allow another part of the load to be brought to the platform and to be secured to the first part and again withdrawn into the derrick. When all the load has been assembled and if desired pipes attached the platform 10 is withdrawn and by sequentially connecting the guides 21, 14, 11 it can be lowered into the well while guided by its collar 25.