Self-locking threaded connection partially in non-locking engagement

A threaded connection comprising a first tubular component and a second tubular component,

• the first tubular component comprising a first pipe body, a male threaded zone and a male terminal surface, the male threaded zone being arranged along a longitudinal axis (X) of the threaded connection between the first pipe body and the male terminal surface, said male threaded zone comprising a first male threaded portion and a second male threaded portion, the second male threaded portion being arranged along the longitudinal axis (X) between the first male threaded portion and the first pipe body, the first male threaded portion having threads with a first male root width and the second male threaded portion having threads with a second male root width, the first male root width decreasing in a direction oriented from the male terminal surface towards the first pipe body, the second male root width being constant along the second male threaded portion,
• the second tubular component comprising a second pipe body, a female threaded zone and a female terminal surface, the female threaded zone being arranged along the longitudinal axis (X) between the second pipe body and the female terminal surface, said female threaded zone comprising a first female threaded portion and a second female threaded portion, the first female threaded portion having threads with a first female root width and the second female threaded portion having threads with a second female root width, the first female root width decreasing in a direction oriented from the female terminal surface towards the second pipe body, a tooth of the female threaded zone arranged closest from the female terminal surface having a largest female thread root width of the female threaded zone,
• wherein the male threaded zone and the female threaded zone are partially made up in a self-locking arrangement in order to provide a locking region and a non-locking region in the threaded connection, the locking region being formed in the made-up state of the threaded connection by cooperation of the first male threaded portion and the first female threaded portion, the non-locking region being formed in the made-up state of the threaded connection by cooperation of the second male threaded portion and the female threaded zone,
• and wherein a female distal thread of the locking region has a width such that
• FDTW/TH>=125%, in which FDTW is a tooth width of the female distal thread of the locking region and TH is the tooth height of said female distal thread.