Demolition and Recycling - Oil rig

Scotoil of Aberdeen Cutting Sub-sea risers from Oil Rigs

Scottish company Scotoil uses purpose-developed Echidna equipment for cutting sub sea risers from oil rigs in the North Sea.

Sub-sea risers are pipes that connect an offshore drilling rig to the sub-sea system. When the oil-rig is decommissioned, the risers must be removed and cut down to manageable size pieces for dismantling and materials recycling.

The sub-sea risers are generally made up of several layers of hardened plastic, three layers of 10mm steel and then the inner stainless banded core. Often there are gases trapped between the layers.

Subsea structures and risers from oil-rigs are removed from the sea bed in sections using a guillotine machine and then taken to the Scotoil onshore facility in Aberdeen. Although efficient for the offshore campaign using the guillotine, the ends are closed meaning that they must be cut using grinders and/or hand-held cuttoff saws to open the sections for cleaning

Using the composite blade on the D24HS machine, Scotoil are now showing the increased safety aspects of this method - removing the operator using a Stihl saw at a close proximity removes the chance of injury by trapped gas within the risers causing potential harm.

Cutting time is also reduced. Cutting through one of the sub-sea risers with the Echidna D42HS high speed diamond rocksaw reduced a 40 minute job down to 6 minutes.

For more detailed information contact Craig Smith at Scotoil, Aberdeen Scotland.



Diamond rocksaws with composite blade