Abstract: An electromagnetic coupler includes first and second coupling elements for mounting on respective first and second support elements. The first and second coupling elements include respective first and second annular bodies each including a high magnetic permeability material that houses a conductive winding and an open transverse section. The first and second bodies have complementary shapes that when two support elements respectively receiving the first and second coupling elements are coupled, the first and second bodies form a structure enclosing the first and second conductive windings. The first and second conductive windings are respectively positioned in the first and second bodies such that respective surfaces of the first and second conductive windings are substantially parallel when two support elements respectively receiving the first and second coupling elements are coupled.

Abstract: A rotary drill stem for a well including a central tubular element, and first and second connectors each including a threaded portion that can connect the element to another element. At least one of the connectors includes a chamber in communication with a pressure outside the chamber. The connector includes an annular signal transmission coupler. The annular coupler includes a ring having an annular coupling surface. The coupler includes an insulating support that leaves the annular coupling surface free. The coupler includes a piston surface axially opposite to the annular coupling surface. The annular coupler forms a piston.

Abstract: An electromagnetic coupler includes first and second coupling elements for mounting on respective first and second support elements. The first and second coupling elements include respective first and second annular bodies each including a high magnetic permeability material that houses a conductive winding and an open transverse section. The first and second bodies have complementary shapes that when two support elements respectively receiving the first and second coupling elements are coupled, the first and second bodies form a structure enclosing the first and second conductive windings. The first and second conductive windings are respectively positioned in the first and second bodies such that respective surfaces of the first and second conductive windings are substantially parallel when two support elements respectively receiving the first and second coupling elements are coupled.

Abstract: A rotary drill stem for a well including a central tubular element, and first and second connectors each including a threaded portion that can connect the element to another element. At least one of the connectors includes a chamber in communication with a pressure outside the chamber. The connector includes an annular signal transmission coupler. The annular coupler includes a ring having an annular coupling surface. The coupler includes an insulating support that leaves the annular coupling surface free. The coupler includes a piston surface axially opposite to the annular coupling surface. The annular coupler forms a piston.