R4D-S, Dent in subsea environment – Africa
High-performance composite repair solution for pipe reinforcement
Overview
The objective of the repair performed by 3X ENGINEERING and its local distributor was to reinforce a damaged subsea pipe section over 2.5 meter length, due to dent defect (13,1 % dented depth) situated at 16 meter depth with zero visibility.
Results
Divers and 3X were working together to repeat each steps of the implementation with ZERO VISIBILITY. Zero injury, schedule respected and repair design controlled conclude this job. A special thanks to client representatives and divers team for their precious help for their precious help to complete this project successfully in the best conditions.
 Defect type |
Dent defect in subsea environment with ZERO VISIBILITY |
Details |
36” OD – operating temp. 25°C – max. op. pressure 362 psi |
Location |
AFRICA |
3X Product type |
REINFORCEKiT 4D Subsea (R4D-S) |
SCOPE OF WORK
After Finite Elements Analysis (FEA), 50 composite layers of REINFORCEKiT 4D SUBSEA (R4D-S) product have been determined to perform the reinforcement designed for 5 years.
Underwater, several preliminary operations (sediments excavation, removal of concrete and existing coating, marking of the surface to be wrapped) have been performed before the essential step of surface preparation (grit blasting) to get a good surface roughness (60µ minimum surface profile).
3X wrapping reinforcement has been performed following several stages :
- A foot print of the dent has been done in order to manufacture appropriate composite rigid plate.
- Primer application on the defect, using a dispensing gun, to provide a good adhesion of the composite materials.
- Five rigid composite plates recovered with filler positioned over the dent and strongly fixed with ratchet belts during curing time of 3 hours (illustration picture).
- Kevlar® tape pre-impregnated with X subsea resin (using special 3X device called BOBIPREG) wrapped around the pipe.
82 Kevlar® rolls were necessary to cover the dent with the appropriate thickness composite needed. - Finally, a neoprene soft cover has been applied to protect the repair from shells and other sea elements.
