Sandblasting: the Origins of Abrasive Blasting
When sandblasting was invented in 1870, the process had a profound impact for various manufacturers. Although sandblasting is now outlawed in many countries due to the risks of the dangerous lung disease silicosis, it was the basis for all forms of abrasive blasting that now form a vital part of numerous manufacturing industries across the world.
Sandblasting was invented by Benjamin Chew Tilghman, an American soldier born in Philadelphia, Pennsylvania. It is believed that he came up with the idea for sandblasting after seeing the effects of wind-blown sand on windows in the desert. In 1870 he filed a patent for the sandblast process in the US listing many uses for it including sharpening files, engraving, cleaning boilers and enhancing wood grains. A patent was issued in the UK the following year.
Benjamin was awarded the American Institute of the City of New York’s Great Medal of Honor and the Franklin Institute’s Elliott Cresson Medal for his invention. He went on to refine the process for various other manufacturing techniques taking out a number of patents. In 1879 he moved to the UK and set up sand blasting businesses in London and Altrincham.
From Benjamin’s initial invention a number of new abrasive blasting techniques were developed including Thomas Pangborn’s sand blasting machine developed in 1904, which combined the use of abrasive materials with compressed air.
The first blasting enclosure was patented in 1918 to protect workers from the dangers of breathing in sand particles when blasting. Since then a huge variety of blast cabinets have been developed including pressure fed cabinets, suction principle cabinets and wheel blasting cabinets.
Wheel blasting, which uses centrifugal force to propel the abrasive against an object, was patented in 1932 and wet blasting was developed by Norman Ashworth in the 1950s as an alternative to sand blasting after it was banned in many countries.
In the early 1900s most people believed that sharp edged abrasives like silica sand were the best way of blasting. It was later proved that this was not the case and by 1939, blasters were using a variety of other materials as an alternative to sand including aluminium oxide, coconut shells, copper slag, fruit stones, glass beads, plastic abrasives, powdered abrasives, quartz, silicon carbide, steel grit and walnut shells.
However, even using these new types of abrasive, blasting still posed a number of health risks, particularly in portable air blasting and blast rooms. Abrasive blasting technology therefore had to adapt over the years to make blasting safer for operators. This included the introduction of various types of personal protection equipment such as blast helmets, blast suits and respiratory equipment.
Supporting technology has also emerged including abrasive recovery equipment, dust extraction systems and dust collectors which increase the efficiency of blasting operations. spray booths and spray room technology has also developed alongside blasting technology as many manufacturers require facilities for both surface preparation and finishing.
The abrasive blasting industry has grown exponentially since 1870. Blasting technology has come a long way and changed a lot and although blasting with sand is no longer considered the best method of abrasive blasting, Benjamin’s idea is still a vital part of a huge array of manufacturing operations.