Deep Water Cathodic Protection Survey with the SunStation

A subsea cathodic protection inspection of 2 SC Risers on a SPAR structure in the Gulf of Mexico. The ROV data has been cropped by the letter box, and certain shots have been blurred to protect the privacy of the operator. In the video, the ROV (remotely operated vehicle) approaches the SunStation monitors, which are connected to permanent zinc reference electrodes at critical area of the riser. The light from the ROV activates the SunStation when it is aimed at the soalr panels, enclosed in the housing. The SunStation requires no batteries, and is rated for depths up to 10,000 feet (sea water). Once the ROV captures the readings from the readout, it has enough data to be considered a full cathodic protection survey. This sort of survey can be done any time an ROV is in the area for any type of other work, as all it needs to complete the inspection of the SunStation is a light and a camera. More information is available at stoprust.com.

The readings are as follows (for CP engineers):

Left Side reads SPAR Hull Potential
+132 mV vs Zn sw.= (-) 0.918 V vs Ag/AgCl sw.

Right Side reads SCR potential
-022 mV vs Zn sw. = (-) 1.072 V vs Ag/AgCl sw.

Bottom is the calibration offset

Category:

Science & Technology

Tags:

• sunstation
• sun station
• cathodic protection
• monitoring
• subsea
• corrosion survey
• polatrak
• underwater inspection