Search
Filters
Close

Monitoring And Controlling Cathodic Protection Without Using Reference Electrode ― Cathodic Production Effectiveness Margin From Multielectrode Sensor

There are mainly two commonly adopted criteria for controlling CP. One is the polarized potential criterion and the other one is the polarization shift criterion1. These criteria are not the true criterion for cathodic protection; they are the surrogate criteria (see below). The polarized potential criterion is to control the instant-off structure-to-electrolyte potential within a specified range. For example, the instant-off potential should be between -0.85 and -1.2 V vs Cu/CuSO4 (VCSE) for pipelines buried in soil. The polarization shift criterion is to control the polarization of a CP-protected structure to a given minimum value and this minimum value is usually 100 mV. The polarization is determined either by the difference between the corrosion potential of the structure measured before CP is applied and the instant-off structure-to-electrolyte potential, or by the difference between the depolarized potential of the structure and the instant-off structure-to-electrolyte potential.

Product Number: 51322-17872-SG
Author: Lietai Yang, Xiaodong Sun
Publication Date: 2022
$0.00
$20.00
$20.00

The commonly accepted practice for monitoring and controlling cathodic protection (CP) is to measure potentials of the structure with a reference electrode which sometimes requires maintenance and has a limited service life. A coupled multielectrode array sensor (CMAS) with only solid components is maintenance free and may last as long as the CP-protected structure. This paper discusses how to use a new parameter from the CMAS for monitoring and controlling CP without using a reference electrode. This parameter has been called CP effectiveness margin (CPEM) and has a value of 0% when the CP starts to be adequate and 100% when the CP starts to be excessive. When used together with the potential-measurement methods, the CPEM from a highly robust CMAS probe may provide an independent and real-time indication for the effectiveness of the CP systems and serve as a complimentary method for CP assessment.  

The commonly accepted practice for monitoring and controlling cathodic protection (CP) is to measure potentials of the structure with a reference electrode which sometimes requires maintenance and has a limited service life. A coupled multielectrode array sensor (CMAS) with only solid components is maintenance free and may last as long as the CP-protected structure. This paper discusses how to use a new parameter from the CMAS for monitoring and controlling CP without using a reference electrode. This parameter has been called CP effectiveness margin (CPEM) and has a value of 0% when the CP starts to be adequate and 100% when the CP starts to be excessive. When used together with the potential-measurement methods, the CPEM from a highly robust CMAS probe may provide an independent and real-time indication for the effectiveness of the CP systems and serve as a complimentary method for CP assessment.  

Also Purchased