The nut and bolt connection first appeared in the 15th century, although the threaded fastener came into existence sometime earlier in the form of wood screws. Following the advent of the Industrial Revolution, nuts and bolts became commonplace. The invention of the lathe in 1800 enabled threads of any pitch and diameter to be made with a greater degree of precision and reproducibility. The introduction of standardisation by Whitworth and Sellars led to the interchangeability of components and further enhanced their usefulness. The incompatibility of the Whitworth and Sellars systems was one of the factors which resulted in the establishment of the ISO system, which is slowly being adopted world-wide. This paper focuses on stresses in threaded connections, looking at fatigue failures.
