THE NETHERLANDS:

Reducing damage to umbilicals and risers

Lankhorst Mouldings BV, the Netherlands, has developed a new riser fender that will be installed on two, dynamically positioned semisubmersible newbuilds for Petrodrill, a consortium formed by Pride International and Brazil’s Maritima, for work offshore Brazil. The Carlos Walter is being fitted with the new fenders in Capetown, South Africa. The other rig, Brazil, is in transport from Daewoo Heavy Industries.

Fender system with its six plastic fins strapped onto the riser.

The fender system (see figure) comprises plastic fins about 9-ft (2.7 m) long, in six pieces that are clamped onto the riser radially. They are arranged along the length of the pipe more or less continuously, allowing room for umbilical clamps. A typical 65-ft riser would require six fender sections, or about 36 individual beams. Vulnerable choke and kill lines can lie between the fins and thus gain protection. The fender system can also be used for horizontal storage and stacking.