Does anyone know if there is a segment in AWS D1.1 Structural Steel Weld Code that states anything related to grinding on welds and this not being acceptable?
5.24.4.1 Requires that welds ground flush may not reduce the thickness of the thinner base metal by more than 1/32" or 5%, whichever is less.
5.62 explicitly allows grinding in the use of repairs, but it does prohibit nicking or gouging the base metal.
The visual inspection required in 6.9 is generally understood to be performed before grinding flush, caulking, machining, or any other code-allowed finishing of the weld. This would not preclude repairs by grinding, such as removing excess reinforcement or overlap.
Other than that, I believe grinding is allowed unless addressed specifically in the contract documents.
when properly done, flush ground welds have the best long-term performance of any other weld finish. stress concentration points are bad news for cyclical loadings. ground flush metal is better for visual inspection, magnetic particle NDT, and ultrasonic NDT. visual weld inspection needs to be done after any finishing techniques that alter the weldment metal. Caulking and coatings occur after inspections. ground flush finish isn't necessary for most applications... but just wanted to stress that it is not a bad thing if it happens.
As a point of interest ( to me, anyway) NHRA [the National Hot Rod Association] says this regarding construction of roll cages and roll bars.
" Any grinding of welds prohibited. "
