Wedge thread connection for tubular goods

A method for forming a tubular, the method comprising:

• providing a joint of casing having a central longitudinal axis and an integral pin end with an external male threaded zone having external male threads positioned thereon, the joint of casing having an internal diameter D1 and a metal-to-metal sealing surface disposed between a lower most thread and a terminal end of the integral pin end;
• and
• forming an internal annular recess into the joint of casing at the integral pin end, the internal annular recess having an internal diameter D2 that is greater than D1, the internal diameter D2 being the same along a longitudinal length of the internal annular recess, and the internal annular recess disposed longitudinally along an inner surface of the joint of casing, such that:
• a virtual plane perpendicular to the central longitudinal axis intersects both the internal annular recess and the external male threads disposed on a lower portion of the integral pin end;
• and
• wherein forming the internal annular recess comprises choosing a longitudinal length of the internal annular recess such that the internal annular recess is not disposed longitudinally along an inner surface of the joint of casing radially adjacent to the portion of the external male threads disposed on an upper portion of the integral pin end so as to maintain mechanical strength in the upper portion of the integral pin end on which the portion of the external male threads is disposed.

A tubular joint of casing, comprising:

• a first joint of casing comprising a central longitudinal axis and an integral pin end with an external male threaded zone having external male threads disposed on a pin portion of the integral pin end and a metal-to-metal sealing surface disposed between a lower most thread and a terminal end of the integral pin end;
• wherein said first joint of casing has an internal diameter D1, said first joint of casing further comprising an internal annular recess having an internal diameter D2, wherein D2 is greater than D1, the internal annular recess disposed longitudinally along an inner surface of the first joint of casing, such that:
• a virtual plane perpendicular to the central longitudinal axis intersects both the internal annular recess and the external male threads disposed on a lower portion of the integral pin end, and the internal diameter D2 of the internal annular recess is the same along a longitudinal length of the internal annular recess L1;
• and
• the internal annular recess is not disposed longitudinally along an inner surface of the first joint of casing radially adjacent to the portion of the external male threads disposed on an upper portion of the integral pin end so as to maintain mechanical strength in the upper portion of the integral pin end on which the portion of the external male threads is disposed;
• and
• a second joint of casing comprising an integral box end with an internal female threaded zone having internal female threads disposed on a box portion of the integral box end, wherein the external male threads of the first joint of casing are configured to engage with the internal female threads of the second joint of casing.