That brought 100 pieces found, check that it is Roy 9 pieces and when put to do.Smooth surface found that the surface roughness values cannot be welded according to STD 3 pieces.
Specimens were examined 100 pieces found nine pieces that are welded pieces and when to check a flat surface that a piece of the track surface is not as STD. 3 pcs.
Specimens tested check 100 pieces found a piece of a 9 pieces. And when the investigating the smooth, found a piece of the surface roughness value is not based on STD. 3 piece.