Laminating repair methods

Figures 12.14—12.17 show applications of the ProAssure products. It can be seen that overwrap repairs can be successfully applied on the platform, in the splash zone as well as in the sea. Obviously the complexity increases as repairs move from dry to wet and subsea environments. This is not only restricted to application of the composite laminate but also to related activities such as removal of existing coatings and surface preparation, as well as additional requirements such as the need for scaffolding, absailers and/or a service barge. A similar scenario applies to the clamp repair solution, which is generally advantageous over the overwrap repair method in cases of deeper...

Backing and Tear-repair. The methods and materials proposed for lining include the following (a) mulberry paper attached with starch (rice or wheat), methylcellulose, or carboxymethyl-cellulose adhesives (18 19), (b) contemporary tapa attached with starch or cellulose-derived adhesives (20 21), (c) nylon laminating tissue and heat-set polyamide resin (22) and (d) stitched backings. 

Lamination Shop. This shop has four restorers who keep an Arbee machine in constant use, laminating material that does not lend itself to other methods of repair. Polyethylene film and Japanese tissue are used to make a sandwich for the damaged artifact in a process that uses application of heat, then pressure with metal rollers, to complete the cycle. 

Scarfing Method of preparing the damaged section of a laminated composite structure for repair. 

After preparing of the pipe surface and applying the putty, the composite laminate is applied circumferentially along the cleaned area from one side to another side. The number of required layers is determined by designer based on a proper design method. All of the design methods are explained in previous sections. The typical section of a pipe repaired by overwrap system is shown in Figure 10.2. 

The method for determining the repair laminate/substrate interface toughness parameter (energy release rate) for pipes with through-wall defects is briefly described... 

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