Cathodic Protection / Corrosion Audits

Purpose

A corrosion audit on an existing corrosion protection system can provide the following information;

  • Areas of concern (such as coating defects, under / over protected areas)
  • Methods to improve the operational effectiveness and efficiency of a system
  • Extend periods between planned maintenance
  • Quantify the remaining life of the system
  • Detailed monitoring strategies / integrity management systems

A corrosion audit on existing buried or immersed assets where a corrosion protection system has not been installed can provide the following information;

  • Type of corrosion protection system to be installed
  • Conceptual design parameters

Techniques

Audits are performed through various techniques, including (but not limited to);

  • Close Interval Potential Survey (CIPS) – identifying effectiveness of cathodic protection system between test point installations for the entire buried / immersed length (ensuring complete coverage)
  • Direct Current Voltage Gradient (DCVG) Survey – identifying coating defects (holidays)
  • Soil Resistivity Surveys – identifying the corrosiveness of the soil as well as allowing corrosion system type to be selected, and design to be completed
  • Electrical Interference Studies – to third party structures / transit systems / overhead power lines
  • Visual, Mechanical and Electrical Inspection of system components – identifying, testing and marking all aspects of an installed system to produce straight line drawings and detailed report
  • Current Injection Tests – to determine actual current requirement of asset to enable system type selection to meet required design life

Detailed proposals / scope of works are issued on a site specific basis.