The absence of reliable historical information about a pipeline together with the presence of unique vulnerabilities makes integrity management of early generation pipelines a challenge. Bell hole inspections, often referred to as “direct examinations” often represent unique opportunities to learn valuable information about pipelines for which historical information is limited. The paper describes how bell hole inspections can contribute to an improved understanding of the integrity of early generation pipelines. There are two objectives for this paper: 1. Provide background information related to early pipeline materials, construction, and inspection practices to help inspectors and integrity assessment personnel interpret what they have found during the course of their inspections. 2. Describe supplemental observations, inspections, and measurements that are useful when inspecting early generation pipelines, and The paper includes a summary of early generation pipeline materials and construction practices as a basis for interpretation of features observed during bell hole inspections. Pipe surface features which are characteristic of various manufacturing or fabrication processes and which potentially impact pipeline integrity are illustrated. Nondestructive examination methods, and their role in evaluating flaws and pipe properties specific to early generation pipelines are described.

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