The hunt for oil and gas is taking place in ever deeper water as more easily exploitable reserves are diminished. Although previously uneconomical, deep-water oilfields are now becoming financially viable but access remains a challenge due to extreme operating conditions. Components such as drill risers must be neutrally buoyant so that they can be held in the correct position. This is achieved with buoyancy modules made from syntactic foams, which comprise thousands of tightly packed micro or macro spheres, depending on operating depth. However, manufacturing inconsistencies can make them unreliable at extreme depths, resulting in costly repairs and possible environmental damage. The CERASPHERE (Development of a low cost ceramic buoyancy sphere) project was set up to create a perfectly spherical, low cost ceramic-coated macro sphere. Project partners have therefore created new elastomeric resin-coated spheres with greatly improved wall strength compared to existing expanded polystyrene (EPS) sphere technology. Computer models involving buoyancy and packing efficiency were used to determine optimal sizing and spacing of the spheres. The new spheres can then be packed and cast with epoxy resin to produce the buoyancy unit. The improved packing density gives greater compressive strength to sustain buoyancy modules as deep as 6 000 metres. CERASPHERE’s success will address current weaknesses in the sector and create new opportunities for SMEs to provide improved buoyancy technology to the oil and gas industry. It will also help ensure Europe’s fuel security and remove the threat of cheaper, inferior products from global competitors.
Buoyancy, ceramic spheres, deep water, CERASPERE, elastomeric resin