Aberdeen-based deepwater buoyancy, insulation and elastomer product specialist Balmoral Offshore Engineering introduced two additions to its drill riser buoyancy portfolio. The new syntactic foams, Durafloat Superlite and Durafloat Superlite-X, are rated to operating depths of 15,000ft; typically 3000-5000ft deeper than industry-standard drill riser buoyancy.
According to Jim Hamilton, Balmoral’s international business development director, drill riser buoyancy can no longer be looked upon as a ‘commodity’ product. ‘Drilling operations in waters of great depth and high currents – such as the Gulf of Mexico and offshore Brazil – demand the deployment of ultra-heavy riser strings.
‘Deepwater buoyancy modules are also substantial in size and weight and are susceptible to damage caused by vessel motion and strong ocean currents,’ Hamilton added.
‘That’s why we had to look at the development of a lower density, lighter weight material that would operate successfully beyond the 12,000ft previously offered. It was stressed in the design brief, however, that the new system should not incur a cost penalty and this has been achieved,’ he explained.
Technical director Dr Bob Oram said: ‘Having successfully developed our range of Durafloat riser buoyancy to working depths of 12000ft, it became clear, as the industry moves into ever-deeper waters, that further product development was required. However, the essential increase in mechanical performance demanded to operate at these depths cannot be accompanied by a reduction in available buoyancy, and so foam density reduction was targeted alongside mechanical performance improvement.’
