Reprint from LINK, Spring 2021

A number of year’s back I was engaged by a Midwestern distributor to review an application problem that had intermittently plagued one of their more important customers. Upon meeting with their customer, I learned the problem occurred during the assembly of a stainless steel Nylon insert lock nut to a like stainless steel screw. Although this was a sporadic problem, when it occurred the customer would experience assembly difficulties like nuts that were very hard to turn, nuts that reached installation torque levels before seating, and in the worst cases, nuts that became totally frozen (seized) in mid-run down position, often breaking the screw in torsion.