Project: Dismantling of degasser tank, May 2011.
Installation: Snorre A, Norwegian Continental Shelf.
Scope: Dismantling of degasser tank: d2.3 m, length 6 m, wall thickness 17 mm. Contents comprising 770 titanium pipes. Total weight 11,500 kg.
Large built-in tank surrounded by pipe trenches, cable trenches and various equipment. Not possible to remove in one piece. Opening to loading site: 1 x 2.5 m. The tank has to be cut into some 20 pieces for removal. Using a Tigair saw would be very time-consuming, and the operators would be exposed to significant vibrations and noise.
Equipment/method: Large diamond wire saw (hydraulic). 4-man team with rigging and cold cutting expertise. The weight of each piece must be under 2 tonnes and can then be lowered using pulleys and removed using a pallet jack. The operators planned and completed the assignment from start to finish without involving other disciplines.
Using diamond wire for cutting is ideal on larger constructions. The contents are cut during a single operation along with the outer shell of the tank. The machine is remotely operated, and the operators can remain at a safe distance from rotating tools, noise and vibrations. Good HSE factors and ergonomics.