INTEGRITY MANAGEMENT FOR PIGGABLE AND NON-PIGGABLE SUBSEA PIPELINES

摘要

There are over 20,000 miles (32,180 km) of pipeline currently in service in the Gulf of Mexico. Approximately 2/3 are transmission pipelines. Of the transmission pipelines, over 96% have a single diameter, and 70% operate between 1,000-2,000 psig (6,895-13,790 kPa). The damage reports were reviewed, and approximately 39% were attributed to corrosion. Internal corrosion damage was reported approximately four times as frequently as external corrosion. The next most common cause for pipeline was associated with natural events, such as subsea land slides and storms/hurricanes. Surveys were conducted with the offshore operators to identify their approaches to integrity management. It was found that they have adopted risk-based approaches to integrity management, and rely heavily upon various monitoring techniques, coupled with the implementation of preventative measures, such as corrosion inhibition, etc. This paper also reviews the classical approaches to demonstrating pipeline integrity, as applied to offshore pipelines and risers - particularly in deepwater. Operators rely upon a variety of monitoring and inspection techniques for determining the condition of their pipelines and risers (condition assessment), since access for direct assessment of pipelines and risers can be very difficult or impractical.