Measurement of the root gap in a T-JOINT weld
root gap - the minimum distance between the ends of the elements to be welded which is measured during the assembly of the butt joint for welding
To measure the root gap, use the top High-Lo arm separately from the main gauge plate . Position the taper gauge in the groove, bringing it into contact with the ends of the elements to be welded as shown by the illustration. Take the value of the desired parameter from the scale denoted by the letter C.