Notes for a Successful Composite Repair

In order to determine a suitable composite repair solution, the operator should provide the following information:

• Pipeline design and operating pressure;
• Pipeline design and operating temperature;
• Pipeline medium;
• Required lifetime of the repair.

Documentation Requirement for Various Operating Conditions

Basic material documentation

Basic material documentation including Technical Data Sheet, Material Safety Data Sheet should be provided by the supplier. Basic data on material chemical compatibility with the working environment should also be available.

Design capability

Organisations who offer a repair option for pressurised parts need to have an understanding of the design issues associated with their product and be able to provide Engineering Calculations with supporting data. Suppliers must have a competent engineering capability.

Surface Preparation

Surface preparation is one of the single most important aspect to determine the quality and success of the pipe repair. The durability of a bonded assembly under applied load is determined to a large extent by the quality of the surface preparation used. For the higher specification duties and for those that are critical to safety, a surface treatment is recommended to promote bonding and to retain its integrity over the required operational period. Details of surface preparation and implementation procedure and standards required should be specified.

Short-Term Test Data

Short term test data should include tensile strength and modulus values in both the hoop and axial directions of the repair. For permanent and medium/ high pressure (> 5barg) loads bond strength tests to demonstrate the efficacy of the chosen surface preparation methods should also be carried out.

Long-Term Durability Data

Satisfactory designs can be achieved for pressures up to 20 barg based on short-term data that has been adjusted by a suitable factor. However, for safety critical service and the higher pressure duties (up to 50 barg), long-term durability data should be provided to demonstrate fitness for purpose. Long-term effects by fluids and exposure to ultraviolet light should be addressed.

Method of Statement and Risk Assessment

A detailed method of statement and risk assessment of the repair work should be documentation accordingly to each repair scenarios. Proper test procedure and standards should be included and implemented at each stage of repair works to ensure compliance. It is necessary to ensure that product applicators are trained and certified by the supplier.

Implementation Documentation

The applicators for each repair should document the repair works with daily site reports and close-out reports with step-by-step implementation photos.

Health and Safety Documentation

Many of the repair methods involve the handling of chemicals which are inflammable and/or toxic and which pose a hazard to personnel. Assessments should be available for all the chemical species concerned and the material supplier should provide documentation. Due attention to suppliers instructions, the use of simple safety equipment, and good housekeeping is necessary.