The tuning of proportional-integral-derivative (PID) control loops was an important change at HollyFrontier’s Navajo Refinery in Artesia, N.M. Its hands-on, “mandraulic” culture was no longer cutting ...

Even though experience is not a material item, it certainly must be considered a valuable 'tool.' By way of experience, good tuners generally know the cause and effect of changes, prior to making them ...