Abstract: An offshore drilling rig contains a heavy-duty support cart that straddles the moonpool and rides on rails. A funnel-shaped hole extends through the support cart, and a cutout on one side of the cart provides lateral access to the hole. The cart can be moved to the region of the rotary assembly, where a length of tubulars can be suspended from the cart. For instance, when the BOP is pulled out for installation of the Xmas tree assembly, the BOP and attached riser can be pulled up above the seabed and hung from the support cart, then moved laterally out of the way while the Xmas tree assembly is installed. This lateral movement lowers the possibility of collision between the BOP and Xmas tree assembly. The BOP assembly can then be disassembled and at a later time, or hung until is needed for an adjacent borehole. In a preferred embodiment, the cart is included on multi-activity rigs with more than one load path, hoist, and rotary assembly.

Abstract: A method and apparatus for transferring tubular stands between a substantially horizontal position on the catwalk and a substantially vertical position at the rig floor entry. In one embodiment of the invention, this is accomplished by moving bundles of individual tubulars to the process area, where a stand make-up/break-out machine, also called a bucking machine, makes up the tubular stands. The bucking machine aligns and stabs the connections and makes up the connection to the correct torque. The tubular stand is then transferred from the bucking machine to a stand storage area or to a trolley pick-up area. When additional stands are needed by the drilling operation, a trolley is moved into position over the trolley pick-up area to retrieve the stands previously placed in the trolley pick-up area. The stands are clamped to the trolley and the trolley is moved from a substantially horizontal position to a substantially vertical position at the rig floor entry.

Abstract: A mooring system that uses combination traction winch/windlass units is improved by adding an additional fairlead at each combination unit location and by increasing the strength of existing combination units, their foundations and the foundations of associated equipment such as fairleads and turning sheaves. By these relatively simple upgrades, the mooring capabilities of the system can be economically augmented in those situations where additional lines are desired, such as in areas subject to tropical revolving storms. Normal mooring, when there is no threat of hurricanes, has the anchor and chain attached to the floating structure by wire deployed from the traction winch. When storm season threatens, additional anchors attached to chain run over the windlass can be added, allowing the number of lines to be doubled. The additional anchors can be installed if the floating structure is conventionally moored or if it is attached to pre-set moorings.