Close Interval Potential Survey
A Close Interval Potential Survey is used to determine the effectiveness of the Cathodic Protection System by measuring the Pipe-To-Soil potentials along the pipeline between test stations, and to ensure they are performing up to NACE SP0169 specified standards. Close Interval Potential Surveys are sometimes referred to as Close Interval Surveys. When practical, interrupted surveys are used to measure the IR-drop free, Instant Off, potentials.
The primary steps taken when performing a Close Interval Survey are:
Allied Corrosion Industries’ field-proven pipeline Direct Assessment specialists are fully trained and Operator Qualified in the technology of taking and efficiently recording Close Interval Survey pipeline potential data.
Some of the typical Close Interval Survey data sets that Allied Corrosion routinely collects are native (un-polarized) potentials, polarized “on” potentials, and instant “off” IR-drop free potentials. The potential data sets are tagged with sub-meter accurate GPS locations, along with major surface physical attributes, which are encountered along the pipeline route, i.e. roads, creeks, fences, power lines, etc…
When rectifiers are to be interrupted, Allied Corrosion Industries’ survey team can accommodate any timing specification that the pipeline owner may require. We are also well versed in handling telluric current interference that typically affects the accuracy of CIS potentials. Allied Corrosion owns and utilizes all the major potential data management software programs. This allows us to furnish potential data sets that can be directly imported into the customer’s data base, thus eliminating the requirement of manually entry of data.
Consequently, when accurate potential data is a primary consideration that can be easily imported into the customer’s data base, Allied Corrosion Industries’ Closed Interval Survey services are the first choice of the pipeline owner/operator.
Allied Corrosion Industries’ personnel embrace the strategy that the job is not finished until the ROW is free of all survey materials. This includes the removal of all making flags, survey wire, crew trash, and/or any other materials used during the survey. Allied takes pride in ensuring that the ROW is left in a cleaner state than before the survey was initiated.
Our crews have over 20 years experience and include NACE Certified CP Engineers, Technicians and Testers. We have performed Close Interval Potential Surveys on over 6,000 miles of pipelines throughout the United States. Our goals of quality, safety, and on time delivery are reflected in our work and performance.