METHOD AND DEVICE FOR DRIVING BORE HOLES, SPECIALLY EXPLORING AND EXTRACTION DRILLINGS IN THE SEA BOTTOM

摘要

The invention relates to a method and a device for driving bore holes, specially exploring and extraction drillings in the sea bottom (40). According to the invention, the sea bottom is slackened by means of a rotating drilling head (10) which is fitted to the lower end of a drill string (5) designed for transmitting torque. The upper end of the drill string is mounted on a floating platform (1), wherein the drill string (5) is composed of at least two telescopically interfitting string parts (6, 7), which during a vertical movement of the platform, e.g. a movement induced by the sea swell, exert a relative movement with respect to each other so that the drilling head (10) rests with a substantially constant force on the surface to be cleared away.