History Of Hex Head Bolts And Nuts
The introduction and widespread use of hex nuts and bolts is the result of innovations in engineering and metallurgical technology. Hexagon nuts and bolts and the tools to use them require strict tolerances. As a standard fastener type, hexagon nuts and bolts are commonly used only after forging, stamping, and machining techniques have been developed before precise hex bolts can be manufactured.
Hex nuts and bolts are part of a fastening system using threads. The thread's history can be traced back to the seventh century BC, when the Assyrian king Senacherib. Sennacherib uses screws as part of the pump that supplies water to the hanging Gardens of Babylon's water supply system. The Greek mathematician Archytas of Tarentum described wood threads in the third century BC, and by the first century BC wood screws were widely used in oil and wind presses. These are usually attached to some kind of permanent handle as a rotating device.
Metal screws and bolts first appeared in Europe in the 1400s, but did not become common fasteners until the 18th century, when machine tools were developed to make them. Between 1770 and 1798, Jesse Ramsden, an English musical instrument maker, Henry Maudslay, an English engineer, and David Wilkins, an American inventor, all obtained patents for thread cutting lathes, which were used to make screw rods. Early screws were often customized with square bolt heads. Replacement bolts are custom made, so they are not in large quantities and cannot be widely used.
Square boltswere common in early applications because they were easier to make using the tools, metals and techniques of the time. The precision of the square head is low, so the wrench may not be the exact size of the bolt, but it is close enough to turn the manual square head. But the square head is large and requires more rotation space. By 1841, Joseph Whitworth, a British toolmaker, and his American counterpart, William Sellers, of the Franklin Institute, had proposed a standardized thread system. As tool makers developed new technologies for mass production, standardized bolts and nuts were soon available.
Between 1856 and 1876, the English metallurgist Sir Henry Bessemer developed the Bessemer process, which produced cheap mild steel in large quantities. Square bolt heads are easier to make when machinists use cast iron and thicker steel. However, as the machinery became smaller and more compact, hex bolts were developed to meet the demand for more compact bolt heads.
In 1830, James Nasmyth, an assistant of Henry Maudslay, designed pioneering milling accessories for his desktop lathes and made a number of hexagonal bolts for a scale model built by the Science Museum in London. By the 1840s, cold heads could be used to press metal. It was not until the 1880s that the Bessemer steel plant began to produce new mild steel of accurate thickness and quantity, and then the cool-machine began to press the hexagon nuts. This innovation means that nuts stamped from flat metal billets and machined to exact tolerances can be screwed to bolts made by the new screw machine in factories anywhere in the country. In heavy industrial applications, larger hexagon nuts quickly replace square bolt heads.
During the two wars of the 20th century, the huge military equipment and equipment maintenance forced manufacturers of war materials to achieve higher standards. The humble hex bolt and nut fastener system is vital not only to the war effort but to every aspect of modern life.