jonasinc
Materials
- Feb 17, 2005
- 23
We are investigating several corrosion monitoring techniques for on-line monitoring and have a few questions:
1. For the Electrical Resistance sensor, we have seen instruments that use two electrodes of different diameters that are both exposed to the flow, instead of both being the same diameter and only one exposed to flow. The change in the difference in resistance is used to calculate the corrosion rate. According to some literature, this is more accurate because it eliminates any resistance differences that are due to the electrodes being at different temperatures. Have you ever used electrodes of different diameters for an ER sensor?
2. We have seen Linear Polarization Resistance probes with two electrodes (one base metal and one platinum electrode) and with three electrodes (a second base metal electrode). What are the advantages/disadvantages of each? Which would you recommend for a field instrument? What is the typical material for the reference electrode for a field instrument? We would prefer not to use a glass electrode.
3. We would also like to measure the corrosion potential using a working electrode made from the pipe material and a reference electrode. What material should be used for the reference electrode? Will platinum work?
4. Is there a minimum distance that the electrodes for different sensors should be separated to reduce or eliminate interferences? For example a set of conductivity electrodes and a set of LPR electrodes or two ER electrodes.
5. Do you have the monitoring equipment for each of the above sensors? If so, would they be available to rent for about 1 month? What is the cost for each instrument for a 1 month rental?
Thank you
1. For the Electrical Resistance sensor, we have seen instruments that use two electrodes of different diameters that are both exposed to the flow, instead of both being the same diameter and only one exposed to flow. The change in the difference in resistance is used to calculate the corrosion rate. According to some literature, this is more accurate because it eliminates any resistance differences that are due to the electrodes being at different temperatures. Have you ever used electrodes of different diameters for an ER sensor?
2. We have seen Linear Polarization Resistance probes with two electrodes (one base metal and one platinum electrode) and with three electrodes (a second base metal electrode). What are the advantages/disadvantages of each? Which would you recommend for a field instrument? What is the typical material for the reference electrode for a field instrument? We would prefer not to use a glass electrode.
3. We would also like to measure the corrosion potential using a working electrode made from the pipe material and a reference electrode. What material should be used for the reference electrode? Will platinum work?
4. Is there a minimum distance that the electrodes for different sensors should be separated to reduce or eliminate interferences? For example a set of conductivity electrodes and a set of LPR electrodes or two ER electrodes.
5. Do you have the monitoring equipment for each of the above sensors? If so, would they be available to rent for about 1 month? What is the cost for each instrument for a 1 month rental?
Thank you
