Flexible risers - is repair a viable option?

Flexible pipes are an assembly of plastic layers and steel wire and strips, some of them interlocked. The plastic layers contain the internal fluid and isolate the pipe structure from its external environment; and the steel wires and strips provide the load bearing capacity for the pipe.

Several of these pipes have suffered damage, occurring either at the manufacturing stage during installation e.g. during reeling, or whilst in-service as risers offshore, during the life of the pipe.

TWI has helped Industrial Member companies in assessing damage, particularly to the thermoplastic layers of the system. In doing so, TWI plastics specialists could identify the cause of the damage and were able to instruct on possible repair methods. TWI's extensive knowledge of plastics, in terms of material properties, processing and welding has led to the successful outcome of a number of projects for three TWI member companies.