Connection device for two lines with overlapping sections

The connecting device (1) has wedge portions (4,5) that interact via a wedge engagement such that inner circumference of the connecting device is adjustable by relative movement of the wedge portions along pipe axis (L). A locking device (6) is arranged in axial direction of the wedge portions so as to lock relative movement the wedge portions. Independent claims are included for the following: (1) line connection assembly; and (2) method for manufacturing line connection assembly.