ABSTRACT
In general, the technology used in cathodic protection (CP) monitoring does not allow for the collection of accurate, consistent, and repeatable data to compare against the criteria for protected systems as recognized by the National Association of Corrosion Engineers (NACE). Moreover, the technology widely used today often requires lengthy depolarization times to measure against the NACE 100 mV polarization criteria1. However, technology is available to accurately collect CP data and can be readily implemented into CP monitoring programs with minimal impact to cost and schedule. This is accomplished by improving the software and hardware used to measure and analyze CP monitoring data to allow the collection of Automated Waveforms. By implementing Automated Waveform Analysis during CP surveys, operators of structures using CP systems can accurately and consistently record CP data to better assess their level of protection. This technology can quantify polarization during the off cycle or predict the time it will take to depolarize a system. These features can reduce survey costs as well as minimize the detrimental effects of leaving systems unprotected for extended periods of time to depolarize.
INTRODUCTION
Cathodic protection (CP) monitoring data is periodically collected and used to compare against recognized National Association of Corrosion Engineers (NACE International) criteria for adequate cathodic protection. However, techniques widely used for cathodic protection monitoring generally do not allow for the collection of accurate and consistent data. Additionally, unlike most other types of regulatory monitoring, most CP data currently collected is not repeatable, nor does it result in the production of traceable and verifiable documentation.
The use of Automated Waveform Analysis during CP surveys, produces accurate and repeatable data. It also can be used to produce traceable quality documents for regulatory verification. Automated waveform evaluation produces data that more accurately accounts for IR (voltage) drop and can serve as a predictor of the true level of polarization afforded a buried structure.
