In 2013 development of a major gas condensate field began in the south-east of the Yamal peninsula to be commissioned in 2017. Natural gas production capacity at the field is estimated to exceed 27 billion m3 per annum. More than 200 wells at 19 sites were to be drilled to harvest these capacities.
During "Yamal LNG" project implementation Velesstroy signed contracts with French companies VINCI CONSTRUCTION and ENTREPOSE PROJETS, with works package including the construction of a world-scale unique facility - four cryogenic tanks for liquefied gas storage.
Each tank can hold 160,000 cubic meters of liquefied gas. The total resource capacity of the field exceeds 1.2 trillion cubic meters. Operating capacity of the gas production, storage and dispatch facilities will be 27 billion cubic meters of gas per year. Never before has Russia seen tanks of such capacities!
The first contract signed for the project in October 2013 covered the construction of tanks’ base slab, external walls, as well as construction of the concrete domed roof. Contracts for the construction of the steel roof, the insides and the external platforms were signed in June and November 2014. Thus, Velesstroy assumed responsibility for the whole construction scope of cryogenic tanks.
Each tank is made of more than 17 500 cubic meters of concrete and 3400 tons of rebars. The concrete grades used in construction are: B25, B45 and B55. 1000 cubic meters of concrete are used for concrete base, 5 300 cubic meters – for the concrete slab, 8350 cubic meters – for the 44 m high tank wall, and 2 800 cubic meters – for the concrete roof. Weight of tanks steel roof made up by 28 sections reaches up to 764 tons. In accordance with the contact, the total weight of steel material for construction of the tank’s internal parts exceeds 2 200 tons while the length of welds exceeds 23 000 meters.
As of today, all four tanks have already been constructed and commissioned.
One of the most critical operations was the use of sliding formwork technology which had never been used by Velesstroy before. Therefore, the employees involved in the construction of the wall, were trained. Theoretical training for all those involved in the process ended with a practical exam, i.e. the construction of an experimental ten-meter wall at a test site. But the real schooling was the construction of the first tank. It became a ground for developing technological and organizational skills, and showed what kind of unexpected things can happen and how to avoid them during the construction of the other three tanks.
It should be noted, that it is the courage and the drive for results of the employees that helps Velesstroy perform the work in time, as well as to overcome the severe climatic conditions, the polar night, storm winds and strong Arctic frosts