Clock Spring® system repair

GRI-98/0151 Evaluation of Plexus MA440 Adhesive and Typical Pipeline Rehabilitation Coatings for Use with the Clock Spring System. Report The Clock Spring system allows repair of pipeline defects without the need for welding and without taking the pipeline out of service, 1998. 

GRI-98/0150 Long-Term Durahihty of the Clock Spring System. Report A monitoring program developed to confirm that the Clock Spring system provides a permanent repair for certain pipeline defects, 1998. 

The use of fiber-reinforced composite materials for pipeline repairs was developed during work at Southwest Research Institute and Battelle in the late 1980s (Fawley, 1994 Stephens and Kilinski, 1994). There are two basic types of composite repair systems preformed (composite sleeves) and wet lay-up (composite wraps). The first commercially available system was Clock Spring , which consists of an E-glass/polyester resin-based composite material preformed into a multilayer coil that is installed using an adhesive (Figure 4.4). 

Figure 6.2 The Clock Spring repair system. Courtesy of Clock Spring Company L.P.

The following references have a wealth of information regarding the Clock Spring composite sleeve repair system ... 

GRI-02/0165 Long-Term Lap—Shear Testing of Clock Spring High Temperature Adhesive. Report The Clock Spring repair system is used as a reinforcement for pipeUnes with corrosion defects and/or mechanical damage, 2002. 

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