SUBSEA TECHNOLOGY
CLEVER COMPOSITE Subsea maintenance? Use composite, advises Jean-François Ribet I
n 2022, most of the oil & gas offshore infrastructures in Northern Europe are ageing and facing harsh conditions. At the same time, we need to continue to operate them without shutdown. Composite has become a key solution
for years now to keep platforms in good shape and maintain their topside and subsea networks with lower restrictions than traditional solutions, no shutdown and no fire permits in most cases. When dealing with subsea pipelines and caissons, the situation becomes more critical. Te maintenance is more challenging and it mobilises more resources. How can operators maintain and repair efficiently the subsea part of an offshore platform?
CASE STUDY: MAINTENANCE OF SUBSEA CAISSONS Tis is the main topic of a project in Northern Europe that 3X Engineering was requested to tackle. Te major challenge was to seal many holes on subsea caissons, considering the cold temperatures and the harsh weather conditions during application in the North Sea, its specific salinity rate, the steel grade and more. After years of development and testing within its R&D department, 3X
of divers and so having a better safety during the application process. Te holes were sealed using specific filler and plates, subsea primer and a certain number of layers of subsea composite made of epoxy resin and Kevlar tape. Te number of layers was calculated according to the standard ISO24817 combined with finite element analysis. Te preparation of the composite was done on the platform and then the latter was given to the divers to install the composite bobbin on the automatic wrapping machine.
3X aims to minimise the use of divers to improve safety
Engineering developed the proper composite to ensure a successful repair. One of the key aspects was to get a resin used as a primer and able to cure at cold temperature while ensuring a good bonding. Te requested adhesion standard was to get a minimum of 5 MPa. Finally, 3X was able to achieve an average of 10 MPa. Tis first step validated, the second challenging part was the field application. To overcome it, an automatic wrapping machine using a wrapping patent developed by 3X was installed around the caissons. It made it possible to wrap hundreds of composite layers in few hours while minimising the use
NEXT STEPS Tanks to many years of experience on onshore offshore and subsea installations, 3X Engineering is continuing to work closely with the main operators in the oil & gas sector. One of the future needs will be to find solutions to maintain and repair the subsea networks in deep water areas, up to 3,000m deep, which means to consider harsher constraints never met until now by exploring new paths in technology for the application process.
Jean-François Ribet is with 3X Engineering.
www.3xeng.com
3X aims to minimise the use of divers to improve safety
48
www.engineerlive.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56
