OREANDA-NEWS. On August 24, 2007 within the framework of implementation of megaproject Kandym-Khauzak-Shady-Kungrad ( Uzbekistan), LUKOIL Overseas through its subsidiary operating company, LUKOIL Uzbekistan, has completed the construction of a linear section of a gas pipeline on the Khauzak block, reported the press-centre of LUKOIL Overseas.

45-kilometer gas pipeline made of German and French corrosion-resistant pipes with the diameter of 711 millimeters and wall thickness of 20.6 millimeters is designed to transport sour natural gas from Khauzak to the tie-in point on Dengizkul-Mubarek main pipeline. Welding and assembly work (by a Kazakhstan contractor, United Construction Company) took 4 months. 75 highly qualified certified welders and 17 welding unit’s operators were simultaneously working at the construction site making up to 85 joints per shift. During these activities a special automatic welding mode for sour environment was applied as per the technology of American company CRC.

Joints were welded from inside with the use of a special centralizer that forms a weld of 8-10 micro-layers with each of them being protected against the aggressive impact of the sour environment. The welding was followed by X-ray and ultrasonic tests to prevent any defects as well as the thermal treatment of welds by heating them to 600 degrees to relieve post-welding stress, restore crystallizing, create a monolithic environment and enhance the corrosion resistance of welds. Welding joint zones were isolated with the use of shrunk-on rings following the positive opinion by the laboratory and technical supervision service.

Main gas pipeline is one of the most important elements of Khauzak gas field infrastructure that will be commissioned at the end of the current year.