Sounds like a fillet weld to me.

Check the applicable construction code for the specific size. Most of the ASME pressure piping codes specify the fillet size as a function of the pipe wall thickness. Also, be wary, the codes sometimes indicate the size of the throat rather than the fillet leg. In that case, remember to multiply the throat by 1.414 to obtain the appropriate size to be listed on the welding symbol.

Al