PIPE JOINT Russian patent published in 2007 - IPC F16L15/00 

FIELD: pipeline engineering.

SUBSTANCE: pipe joint comprises cylindrical coupling provided with inner threaded surface and mounted at one of the ends of the joint, cylindrical adapter with outer thread for engaging with the answered threaded coupling and mounted at the other end of the joint. The diameter of the internal passage of the adapter is equal to the inner diameter of the pipes to be joined and coupling. The coupling and adapter are provided with face stop surfaces located in the sections transient from the smooth inner surface to the inner thread. The planes of the surfaces are perpendicular or inclined to the axis perpendicular to the axis of the coupling and adapter. The section of the coupling and adapter between the stop face and inner thread is provided with groove whose width is 4-6 mm and diameter exceeds the diameter of the hollows of the internal thread by 0.8-1.0 mm. The chamferings are made in the section in the zone of transition from the smooth inner surface to the stop faces of the coupling and adapter and smooth inner surface of the pipe to be joined to the face of the pipes.

EFFECT: enhanced reliability.

2 cl, 5 dwg