Offshore CompoSol Caisson

THROUGH WALL PENETRATION ON A FIRE PUMP CAISSON

For larger diameter, longer lengths of pipework, such as caissons, where the volume and content of turbulent fluid will erode the walls, through wall defects are a continual problem. To repair with clamps is expensive, takes time and usually results in the leak moving to the next weakest point. Also, as the wall becomes thinner, the danger of squeezing the pipe wall, causing catastrophic failure, is greatly increased.

IMG Composites has the solution with its CompoSol Caisson repair system, providing an engineered, designed repair to reinstate the pipework to its original integrity and strength, in an economical, safe and timely manner. All CompoSol repairs are carried out under Cold Work Permits. Depending on size, access and pipe condition, many such repairs have been carried out, down to the splash zone, at up to 5 metres per day.

A major gas storage facility had severe through wall penetration problems on a Fire Pump Return caisson; several clamps had been fitted to provide integrity but leakage was still occurring between the clamps and several new leaks were evident. After removal of the clamps the full extent of the damage was clear; a total of 461 holes were found, ranging from 2 to 100mm, within a 15 metre long section of the caisson.

Preparation was carried out to ST2 standard and the holes plugged. IMG Composites' unique Kevlar Reinforced Epoxy Putty was applied over the 15m section. A fibre sheet was embedded into the mortar to provide additional support. Once cured, a further 3mm of putty was applied. To complete the repair 10 layers of Composite Laminate was applied and compressed into place over 360 degrees using the IMG Composites Uni-Wrap Compression System. Two coats of IMG Composites' single pack epoxy paint, CompoSol Armour, was applied to match the existing platform colouring. The whole repair took 6 working days to complete, and will have a useful life in excess of 20 years. After start up, 8500 gallons per minute of seawater flowed through the caisson - with no leakage.

IMG Composites provides a full Caisson Rehabilitation Service - whatever the cause of the problem:

• Through Wall Perforation
• Wall Loss through Corrosion or Erosion
• Corrosion/Splash Zone Protection

IMG Composites CompoSol Caisson has the solution because it meets all the requirements of ISO 24817 for both Internal and External Type A and Type B defects.