SUB APPARATUS WITH EXCHANGEABLE MODULES

摘要

The present invention is an apparatus and method for use in a well borehole drilled into a formation. The apparatus comprises a work strin g disposed in the borehole. The work string includes at least one modular body portion having at least one receptacle. A modular tool is disposed in the at least one receptacle for carrying out a drilling operation. The modular tool may be a tool for use in drilling a well borehole, it may be a tool for testing a formation surrounding a borehole, or the modular tool may be a combination. For example, one aspect of the present invention provides a modular steeri ng rib. The modular steering rib may also include modular components for sampling and testing formation fluid.