Tubular connection having a parallel chevron thread

A thread form for a tubular connection of the type having a pin member adapted to be made up with a box member to form a pipe joint, comprising:

• a pin member having pin threads with thread crests and thread roots which are adapted to be made up with a mating box member having a complimentary thread structure, said pin thread crests being formed between a stab flank and a load flank of said pin thread;
• said pin thread having a chevron-shaped load flank for engaging a mating chevron-shaped load flank of said complimentary box member to provide a chevron type interfit between the load bearing thread flanks of said pin and box threads;
• wherein said pin thread stab flank forms an obtuse angle theta with respect to the longitudinal axis of the tubular connection and with respect to its adjacent pin thread root whereby the stab flank of said pin thread flares outwardly in the direction away from said adjacent pin thread root;
• and
• wherein said pin thread chevron-shaped load flank is made up of an inner wall portion and an intersecting outer wall portion, said inner wall portion forming an acute angle beta with respect to the longitudinal axis of the tubular connection and with respect to its adjacent thread root whereby said inner wall portion flares inwardly toward said thread root and wherein said outer wall portion forms an obtuse angle alpha with respect to the longitudinal axis of the tubular connection and with respect to its adjacent thread root whereby said outer wall portion flares outwardly from said point of intersection with said inner wall portion and from its adjacent thread root.

A thread form for a tubular connection of the type having a pin member adapted to be made up with a box member to form a pipe joint, comprising:

• a pin member having pin thread with thread crests and thread roots which are adapted to be made up with a mating box member having a complimentary thread structure, said pin thread crests being formed between a stab flank and a load flank of said pin thread;
• said pin thread having a chevron-shaped load flank for engaging a mating chevron-shaped load flank of said complimentary box member to provide a chevron type interfit between the load bearing thread flanks of said pin and box threads;
• wherein said pin thread stab flank forms an obtuse angle theta with respect to the longitudinal axis of the tubular connection and with respect to it adjacent pin thread root whereby the stab flank of said pin thread flares outwardly in the direction away from said adjacent pin thread root;
• and
• wherein said pin thread chevron-shaped load flank is made up of an inner wall portion and an intersecting outer wall portion, said inner wall portion forming an acute angle beta with respect to the longitudinal axis of the tubular connection and with respect to its adjacent thread root whereby said inner wall portion flares inwardly toward said thread root and wherein said outer wall portion forms an obtuse angle alpha with respect to the longitudinal axis of the tubular connection and with respect to its adjacent thread root whereby said outer wall portion flares outwardly from said point of intersection with said inner wall portion and from its adjacent thread root;
• and
• wherein the load flank inner wall portion of said pin member is non-parallel to the stab flank of said pin member, said load flank and stab flank being adapted to engage mating thread portions of said complimentary box member.