Mears Hosts Workshop On ECDA For Cased Pipelines

With the federal Department of Transportation Pipeline and Hazardous Materials Safety Administration (PHMSA) in the process of developing guidelines to further clarify baseline and integrity assessment requirements for cased pipe (per 49 CFR 192 Subpart O code of federal regulations), Mears invited a group of customers to its state-of-the-art test-and-research facility for a hands-on workshop of External Corrosion Direct Assessment (ECDA) applications of cased pipes.

Fifty-six integrity representatives from pipeline and gas utility companies across North America attended the day-long event at Mears headquarters in Rosebush, MI. Speakers included Max Kieba, Central Engineer, Office of Pipeline Safety, who gave directions to attendees on the upcoming PHMSA cased-pipe guidelines. Demonstrations included field indirect and direct inspections of coated and uncoated cased pipe, and a demonstration of wax filling a casing by Royston.

When cased crossings are located in a High Consequence Area (HCA), they fall under the integrity management (IM) requirements and must be in compliance with prescribed milestones. With best estimates, there are thousands of cased crossings nationwide and hundreds, if not thousands, located in HCAs that will be subject to these requirements.

Currently inline inspection (ILI), pressure testing and Direct Assessment (DA) provide the only assessment options for the pipeline industry. But in some cases, obstructions in the pipeline, the expense of pressure testing and the revenue loss from downtime eliminate ILI and hydrotesting as options. This has necessitated the development of DA methods using ECDA to assess cased pipe.

PHMSA, the pipeline industry and Standards Developing Organizations (SDO) are collaborating to provide additional guidance for assessing cased crossings. PHMSA assembled a core team of participants (CASQAT) to develop guidelines and expectations when operators assess cased pipelines using the ECDA process. PHMSA assembled a select group of representatives from NAPSR, PHMSA, AGA, INGAA, NACE and two representatives from contract vendors.

The guidelines will address acceptable protocols and practices when using ECDA to assess cased pipelines. More specifically, how is the baseline assessment to be conducted? What are the requirements for using ECDA? What is a continual process of evaluation and assessment to maintain pipeline integrity? What are the required intervals?

Other issues PHMSA will address are conditions to justify that the threat of external corrosion has been mitigated sufficiently as to not require full re-assessment and determine how to address casings filled prior to the IM rule.

ECDA employs engineering processes to proactively assess locations for the likelihood of corrosion, and to focus remediation where the corrosion exists. Pre-assessment requires the operator to organize the testing, analysis and remediation methods used by categorizing cased crossings into like-similar regions.

The Mears workshop addressed prompters for external corrosion of cased pipelines, including metallic contact, electrolytic contact and atmospheric corrosion. Attendees were given live demonstrations on various testing methods on both coated and uncoated casings including: