Despite the downturn in the industry, a new generation of Semi Submersibles has been developed and put into operation. This so called fifth generation of Semi Submersibles has ambitious goals in regards to operational safety and efficiency. The rig concept includes new ideas on how to make-up and run drillstring components, riser pipe as well as casing and tubing. Doubles, Triples or even Quadruples of pipe are being made-up at special "Mouse-hole stations" including their own mechanized handling and make-up equipment. By this means, many functions such as prefabrication of stands of risers, drill pipe and casing stands can be carried out offline without interrupting or delaying drilling operations. Considerable time- and cost saving is anticipated.
The paper describes the planning, development and implementation of the modular concept of the PowerFrame carrying the fully remote controlled power tongs that were installed on three of those rigs built in Brest/France and in Singapore. Actual field experience from a drilling location was not available when this paper was written (May 2000), as the first rigs are scheduled to arrive on location by June 2000. However, during the commissioning sufficient experience was gained to allow the prediction that the ambitious goals set in regards to time saving will be achieved.