IMPROVEMENTS IN OR RELATING TO UNDERWATER EXCAVATION APPARATUS

摘要

The disclosure relates to an underwater excavation ap- paratus comprising a tube (10) in which a propeller (18) is mounted for rotation. The tips of the propeller blades are formed with jets (30) supplied from a high pressure water supply through passages in the propeller blades. The jets im- pinge on vanes (31) mounted on the tube wall around the propeller to cause the propeller to rotate and thereby draw water through the tube from an inlet at one end to an outlet at the other end to act on the sea bed. The apparatus is parti- cularly useful for excavating trenches on the sea bed and ex- posing previously covered installations on the sea bed and exposing previously covered installations on the sea bed.