The cost of repairing or replacing watermain piping perforated by corrosion is becoming a major item in many municipal budgets, and correspondingly in most individuals’ municipal taxes. Although it is understandable that cast iron failures occur both from a mechanical and age point of view, […]
Sharing of common corridors by gas pipelines and overhead power transmission lines is becoming quite common. However, electrical energy can be transferred from power transmission lines to pipelines through inductive, conductive and capacitive coupling. When a power transmission line runs in parallel with a pipeline […]
The quality of the indirect inspection data is a critical factor in conducting a successful ECDA program. New NACE standards (SP0207-20071 and TM 0109-092), improved instrumentation, experience sharing, and extensive training during the last several years, has resulted in a significant improvement in the accuracy […]
The ECDA process requires a continuous effort from the pipeline operator to improve the reliability of classification and prioritization criteria. Based on the results of the direct examinations, these criteria can be up-graded or down-graded as part of the retrospective evaluation and the number of […]
This paper describes the challenge of integrating specific types of ECDA indications, such as AC enhanced corrosion (ACEC) and DC interference (DCI), under the prioritization criteria recommended by NACE RP0502-2002. Starting from the observation that the risk of corrosion does not always increase with the […]
The 100mV cathodic polarization criterion is being used more extensively on piping in the oil and gas industry which has prompted a discussion on the limits of its use. This paper summarizes the technical literature on the validity of this criterion with respect to elevated […]
The paper describes the theoretical and practical aspects of merging two Indirect inspection tools (i.e. Close Interval Potential Survey and DC Voltage Gradient) into one integrated survey, as used in 2004 during an ECDA project covering more than 21 Km of gas pipelines in Southern […]
Under an Integrity Management Program (IMP) for natural gas transmission lines, the ECDA concept was analyzed and the process was validated from 2002 to 2004. A Plan was developed and implemented in 2004 on one 17 km pipeline and segments of two other pipelines. This […]
Although cathodically protected pipelines are often connected directly to electrical ground in stations and plants, there is little information on the amount of current required to polarize various grounding materials such as copper, tinned copper, stainless steel, silicon iron, and galvanized steel. This paper presents […]
Two leaks were found on a recently installed (1999) pipeline which was coated with extruded polyethylene and protected with directly connected magnesium anodes. This paper describes the use of external corrosion direct assessment (ECDA) principles to identify locations where corrosion could pose a threat to […]
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