CP of riser pulled into j-tube

[JT100]

I was told today that when trying to provide cathodic protection to a riser within a j-tube it cannot be done with sacrifical anodes. Can anyone confirm this and give me some background as to why? I was told in a 'matter of fact' way and when I enquired further I wasnt given much of an explanation beyond "the electrical circuit doesnt work properly". I cannot find much on this via google. Thanks

 

[SJones]

Usually, the riser is sealed into the j-tube which is then filled with chemically treated seawater to provide corrosion protection. There would be no need for anodes in this situation. How would you plan for anodes to survive the pull-in?

Steve Jones
Materials & Corrosion Engineer

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