GB846851A - Improvements in jacking mechanism for mobile marine platforms - Google Patents

Abstract

846,851. Drilling-barges. DE LONG CORPORATION. May 6, 1959 [May 8,1958], No. 15611/59. Class 68(2). A mobile marine drilling or like platform is maintained positively in its raised position by the engagement of pins on the jacking means with holes in the supporting legs. The pins may be locked in the holes and the jacks removed. As described, the legs 20 each have at least two longitudinal jacking bars 22 arranged circumferentially around the leg, each bar 22 being provided with vertically spaced holes 25 to receive pins 182, 226 when projected by presses 196, 228, and with two jacking sections, one section comprising a columnar structure 26 secured, with cushioning 78, 62, to the deck 12 and mounting the pin 226 and its press 228, and the other comprising a box-like structure 106 slidable on the column 26 and carrying the pin 182 and its press 196. The column 26 is slotted at 90 to permit the pin 182 to move vertically with the slide structure 106. The bar 22 is embraced by claws 54, 230 on the stationary column and by claws 220 on the sliding structure 106, which is moved up or down by two pairs of single acting cylinders and pistons 126, 154, the means 154 bearing against a cross-head structure 104 including a heavy plate 100. When the platform is fully raised, the weight is taken by the pin 182 projecting into a hole 25, through the jacks 154, head 104, column 26 and connections with the deck 12. The load is then put partly on to the pin 226 by inserting shims 234 between the plate 100 and a heavy plate 120 at the top of the column 26, the shims being angle-shaped to pass partly around the corners of the column 26 and notched to receive a sliding locking bar which prevents them from shifting. The pin 226 is projected into a hole 25 and, if desired, the jacks 154 may be removed. The pin 182 has spaced bars 186 and a slotted plate 188 welded thereto to form a recess for the head 190 of the piston of the operating press 196. This connection permits the press to be disconnected from the pin 182 and removed, the pin 182 being prevented from retracting by wedges 218 engaged in slots in the structure. Similarly the press 228 may be removed from the pin 226 which also is locked by wedges.