You will need to submit a repair alteration to your AI for approval. If you already have a 2" nozzle on the vessel with no re-inforcement you should be in a good spot. If you want to put in larger nozzles you would need to submit design calculations.
I had a similar issue a few years ago and through investigation determined that the Operators were not warming up the glasses properly when placing them in service. Thermal shock and thermal fatigue was the result. Check to see how they are being commisioned / operated.
None that I am aware of, study the mateial as defined in the sylibus and make sure you read each question twice before answering. Damage mechanism data is key, temperatures etc.
Best of luck, you should do fine.
What is the process fluid? the cathodic ration shouldn't be an issue as you have a large anode. An insulation kit could be considered if you have concerns.
NDT Technicians should always refer to indications as exactly that "linear indications". These methods cannot establish the reason they exist nor should a technician ever refer to an indication as a crack, lap, etc. as this requires metallographic examination.
