OAO “GAZPROM” in collaboration with SNAM and Saipem have developed the first stage of the “Blue Stream” Project, which when completed will be unique for the world gas industry in terms of its parameters and route conditions. During this feasibility stage of the project the following new Research and development tasks were addressed:
- deep water collapse problems (the depths reach 2150 m), including buckle propagation;
- the problem of pipeline protection against an H2S environment (in the near bottom zone H2S concentration reaches more than 14 mg/1);
- the problem of installing a reliable pipeline having a diameter of 610×31.8 mm at gas pressures of 25 Mpa while taking into account the subsea currents;
- construction problems associated with the specified parameters.
Solving such problems required an elaborate and complex set of design tasks and experiments with materials and construction conditions. Special requirements were developed for the pipes and fittings, external anti-corrosion coatings, and the cathodic protection of the pipeline. New procedural documents were developed for deep water pipelining that included: the calculation for determining the strength and stability of the offshore pipelines; an instruction manual for the onshore section of the pipeline designed to carry a gas pressure of 25 Mpa; the necessary software for thermal and hydraulic calculations for the gas pipeline under extremely high pressures.