Drilling fluid diverter system

摘要

An improved method and apparatus for offshore drilling is described which is particularly useful for drilling in deep water from a floating surface vessel. Drilling fluid is introduced into a drill string extending from the vessel into a wellbore in the floor of the body of water. In order to maintain a controlled hydrostatic pressure within the riser, drilling fluids are diverted from the lower end of the riser and are either discharged into the body of water or pumped to the surface through a return conduit adjacent the riser.