cranfield university mahadi abd murad an integrated structural ...

Full cure application: This eliminates the variables of the wet wrap process. The fully
cured composite (e.g. Clock Spring) is taken to the repair location and secured to the
pipe with adhesive. A high compressive strength filler material fills the defects and
voids beneath the composite sleeve in order to ensure a proper load transfer as shown in
Figure 2.20.
Lesmana (2010) claims that with the full cure application, the unidirectional
glass strands which are carefully positioned and aligned, and held within the factory
applied cured resin matrix, have better performance than the wet wrap application
where the ratio of resin to glass, degree of resin saturation, alignment of the glass and
consistency of tension in the repair are difficult to control. In fact, the woven cloth can
allow moisture to penetrate into the composite and weaken the repair. Hence, the
effectiveness and long-term performance are unpredictable. It is likely there have been
many unreported cases where this wet wrap repair has caused huge losses to operators
worldwide.
Figure 2.20: Photos of repaired pipeline using composite wraps based on Clock
Spring (CLOCK SPRING Company L.P., 2005)
52