FOCUS ON SHEET METAL
Soon , more complex shapes such as rails , squares , rounds and double-T beams could be created .
Factories appeared across Europe and America , with ravenous requirements for metal and skilled sheet metal workers . 1861 saw the merger of multiple unions , including the General Tramping Union of Tinplate Worker . This ultimately led to the founding of the General Union of Braziers and Sheet Metal Workers in the UK and Ireland .
However , it was Henry Bessemer ’ s invention of a process in 1856 that made it possible to mass-produce steel cheaply from cast iron that turbo-charged industrial progress . With better strength and durability , steel was rapidly used to build railway tracks , ships etc . Carl Wilhelm Siemens developed his regenerative furnace , further propelling the use of steel . One of the greatest steelmaking centres of the 19th and 20th centuries was in Sheffield , England .
A noteworthy example of sheet metal work is the dome of St . Paul ’ s Cathedral in London , UK , completed in 1708 . The outer dome is made from over 3,000 tons of copper hammered into shape by hand . The dome , a masterpiece of engineering from Sir Christopher Wren and an iconic landmark , dominates the London skyline . The dome symbolises aspirations and the spiritual connection between heaven and earth .
Right : Sir Henry Bessemer . Picture from
Meyers Lexicon books written in German language . Collection of 21 volumes published between 1905 and 1909 .
Image : Shutterstock . com .
The historic locomotive , Rocket , at the National Railway Museum in York , England . Image : Shutterstock . com .
“ With the introduction of the Bessemer process , steel became one of the cornerstones of the world ’ s industrial economy . Available in large quantities and at a competitive price , steel soon supplanted iron in buildings where steel framing and reinforced concrete made ‘ curtain-wall ’ architecture possible , leading to the first skyscrapers . And in shipbuilding , steel began to replace wrought iron plates . Cunard ’ s SS Servia was one of the first steel liners – complete with another innovation , electric
lighting ,” commented WorldSteel , in its ‘ Steel Story ’ chronicle tracing steel ’ s development .
20th century production
Steel production has always gone hand-in-hand with economic development .
“ In the mid-20th century , steelmaking advanced on many fronts . Basic oxygen steelmaking and electric arc furnaces transformed the main production processes , making them faster and more energy-efficient . They even allowed manufacturers to reuse scrap as input material . Along with introducing new primary techniques , steelmakers also improved on traditional techniques of casting and rolling to create sheets , shapes and steel to precise customer requirements . Some of these developments came from Europe , the USA and Russia . But new steelmakers , especially in Japan and Korea , quickly developed their own innovations that , in turn , inspired steelmakers worldwide ,” said Worldsteel .
“ The rise of electric arc furnaces ( EAFs ) in the 1960s paved the way for mini mills and a significant change in the steel industry . Traditional integrated mills based on BOFs require a blast furnace to supply molten iron as input . They are large and costly to build . Mills based on an EAF are different . Using scrap or direct reduced iron ( DRI ) or pig iron as input materials , they are generally smaller and simpler to build and operate . They can also be set up with a smaller level of capital , and that opened the door to a new breed of entrepreneurs ,” it continued .
“ While mini mills were emerging in the USA and Europe , Asia saw innovation in scale and output . Pursuing rapid growth in the 1960s and 1970s , Japan , followed closely by South Korea , developed massive state-of-the-art integrated
Sheet metal aluminium workers .
20 | ismr . net | ISMR February 2024