A Long Time Coming - Whitworth and Standardisation

Looking at the mass of components in this horizontal trunk engine, the significance of the nuts and bolts which hold it together may be lost. They are all ‘British Standard Whitworth’ The Whitworth thread was the world's first national standardised screw thread. It was devised and specified by the industrialist Joseph Whitworth in 1841. Whitworth's standard specified a 55° thread angle and a thread depth of 0.640327p and a radius of 0.137329p (p stands for the pitch). Until the introduction of ‘BSW’, the only standardization was that devised by the different engineering companies for use within their own businesses, although as the Industrial Revolution rolled on some companies personal, standardised threads became the standard among the clients who they served. 

The first, major application of the Whitworth thread system was in the construction of the engines for the gunboats, built by mass-production techniques, by a range of engineering firms, for the Royal Navy for service in the Crimean War of 1854. BSW is a fairly coarse thread and as time went on it became necessary to devise other pitch formulas to suit the thickness or texture of differing metals. Thus, British Standard Pipe (BSP) and British Standard Fine (BSF) appeared, as well as American Fine (AF) and British Association (BA), although these standards are gradually being supplanted by a new, single measure- Metric.