DRILL PIPE

摘要

The invention relates to a drill pipe, particularly for a drill string, having an outer and an inner pipe (3), a female connector (4) with an internal thread at one end of the drill pipe (1), and a male connector (5) with an external thread at the end opposite from the female connector (4), wherein the inner pipe (3) is arranged substantially concentrically in the outer pipe (2) and the drill pipe (1) has a centre region (8) with an internal diameter. The outer pipe (2) has an inwardly thickened wall portion at an end region (7) on the male connector side, having a smaller internal diameter than the internal diameter of the centre region (8), and the internal diameter of the outer pipe (2) remains substantially the same at an end region (6) on the female connector side in relation to the internal diameter of the centre region (8).