摘要 |
There is disclosed a method for the explosive welding together of sections of large diameter metal pipe of the kind used in the construction of high volume oil and gas pipelines. In the method, internal and external band charges of welding explosive are simultaneously detonated adjacent to overlapped telescoped pipe ends. The explosive band charges have a tapered or wedged shape in the width cross-section of the band and are placed so that the thicker edge of the band is closed to the narrow diameter of the female flared pipe area and initiation is made along the thicker edge. The velocity of detonation of the initiating explosive is selected so that welding charges are simultaneously detonated around the pipes while maintaining the detonation fronts at superimposed locations and at a large angle to the pipe axis. This avoids unbalancing forces on the pipes and minimizes the collision of circumferential shock waves thus preventing pipe damage and imperfect welds. |