That would probably be a question better asked within your organization. Do they want to track number of occurances, length/width/volume of repair, man hours, costs, individual equipment, equipment make/model, equipment type, equipment mfgr etc?

The best thing to do in my opinion is for you to evaluate what data you have to enter then decide what you want to get out. If the data going in does not support the data going out you must modify the input or output.

To suppliment Gerald's excellent advice.

You will need to have a strong understaning of welding process control and variables.

I suggest you purchase a book... "Total Welding Management"  By J.R. Barckhoff, PE.

While the main thrust of the book is really centered in manufacturing, the process of management provided will help you to know which data is important to capture and how to look logically at your processes in order to manage them with the highest quality, productivity as well as knowing which supplies are critical to your workers succsess.