09:29 Oct-05-2006 Charlie Jackson Consultant, - Trainer/Inspector Northern NDT Ltd, United Kingdom, Joined Sep 2006 6
This may seem like an obviuos to some but where did the figure of 150mm/s or 6" /s come from. Was it connected to the speed of early pulsers or just chosen as 'that seems about right'.
I have seen exponents of the higher speed with the smaller overlap and those who probe methodically slowly in backward sweeps. Accepted that both ways are in the search mode and see no difference in operators of integrity and experience being slow or fast when looking for discontinuities it seems very much a personal thing. Ive discounted the 'lazy w' merchants who slow or fast are obvious to most.