This paper will review the history of pipeline repairs. Prevailing codes, standards , design guidance’s and regulation typically permit several types of repairs: namely: replace pipe as a cylinder, repair by grinding or buffing out a defect, weld overlays techniques, utilizing a steel reinforcement sleeve or utilizing a composite reinforcement sleeve or composite wrap. This paper will review the history of the technology and the efforts to document and codify consensus standards such as ASME PCC 2 Article 4.1, ASME B31.8s, ASME B31.4 and ISO 24817. Contemporaneous issues related to the subject will be addressed as well of the durability of the aforementioned repair methods.
Globally pipeline operators are required to operate their pipelines in a safe and reliable manner, preventing any unplanned loss of containment, and ensuring the asset continues to run reliably delivering a profit for the pipeline owner/operator. Most pipeline operators are required to maintain their pipelines to an approved code either by National Regulators and/or insurers with the aim of improving safety of the pipeline and unplanned losses of containment. Most National Regulators guidance for the repair of pipelines refers to either ASME B31.4 for liquid pipelines and B31.8(S) for gas pipelines, while for process piping most operators complete repairs following the ASME PCC2 Article 4 guidelines. These guidelines are credible and are globally accepted as being an effective method to operate and maintain pipelines. This paper with reference to the three ASME guidelines highlighting the acceptable repair methods and also looks at the requirements of ISO TS 24817 and highlights how this does and does not fit into the maintenance of high pressure pipelines.