A critical step in ensuring that a pipeline is fit and healthy for operations is continuous scraping “cleaning” and frequent scraping inspection. If scraping activities are not properly performed, pipeline integrity can be at risk.
In a case study, numerous networks of pipelines were found to be operated with different experiences and internal guidelines. This variation led to impact on pipeline integrity in terms of metal loss as well as several other issues such as leaking doors, scraping tools being stuck or damaged, valves passing, and signal passage indicators “SPIs” failures. Therefore, a systematic approach was initiated to review the different practices, procedures in an internal comparison with various experiences, and benchmarking with international users.
The objective was to adopt best practices and develop consistent guidelines for scraping operation by focusing on the major areas such as standard piping layout of scraping facility, valve selection strategy, operation instruction of scraping activity, operation and maintenance of scraper doors, deployment of non-intrusive scraper passage indicator, and scraper tool design selection. A success criterion was also developed by defining the scraping efficiencies, which is the percentage of actual versus planned scraper runs.