The recently developed Localized Corrosion Monitoring (L.C.M.^TM) technique has demonstrated its capability in real-time corrosion monitoring of various types of localized corrosion in a number of applications (e.g. oil/gas production, refineries, water treatments). The technique is based on the current and potential measurements on one-working electrode in a three-electrode configuration.

The L.C.M.^TM technique operates in a potential/current cyclic mode. During the first phase of the measurement cycle, the open circuit potential of the working electrode (WE) is measured. This is then followed by a period of potentiostatic control. During the free potential and potential hold periods, information on the extent and nature of localized activities on the WE is obtained via potential and current transients measurement, respectively. *

The main advantages of L.C.M.^TM are:

1. improved correlation between current and potential measurements of the working electrode;

2. provide quantitative measure of localized corrosion events and their rates;

3. discriminate between various types of localized corrosion;

L.C.M.^TM, incorporates a proprietary analysis software to provide automated quantitative evaluation of the localized corrosion behaviour.The amplitude, frequency, duration and time distribution of the localized events are determined from potential and current measurements. The L.C.M.^TM system enables the corrosivity of a service environment to be appraised continuously, allowing corrective actions to be implemented to mitigate damages.

An example of localized corrosion amplitude measurements is shown below:

Figure 1. Potential time record of carbon steel electrode in a simulated oil flow line environment.