Английский для сварщиков. Гричин С.В. - 27 стр.

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Text 1. Welding History - A Story of Harnessing Heat
Joining metal and welding history go back several
millennia starting in the Bronze Age then Iron Age
in Europe then the Middle East. Welding was used
in the Iron pillar in Delhi, India, about 310 AD,
weighing 5.4 metric tons (picture at left). The
Middle Ages brought forge welding, blacksmiths
pounded hot metal until it bonded. In 1540,
Vannoccio Biringuccio released De la pirotechnia,
which includes descriptions of the forging operation.
Renaissance craftsmen gained skilled in the process,
and the welding continued to grow during the
following centuries.
Welding was transformed during the 19th century. In 1800, Sir
Humphrey Davy invented the electric arc, and advances in welding continued
with the metal electrode by a Russian, Nikolai Slavyanov, and an American,
C.L. Coffin late in the 1800s.
Acetylene was discovered in 1836 by Edmund Davy, but was not
practical in welding until about 1900, when a suitable blowtorch was
developed. At first, oxyfuel welding was the more popular welding method
due to its portability and relatively low cost. As the 20th century progressed,
it fell out of favor for industrial applications. It was largely replaced with arc
welding, as metal coverings (known as flux) for the electrode that stabilize
the arc and shield the base material from impurities continued to be
developed.
In 1881 a Russian inventor, Benardos demonstrated
the carbon electrode welding process. An arc was formed
between a moderately consumable carbon electrode and the
work. A rod was added to provide needed extra metal.
Thermite welding was invented in 1893, another
process, oxyfuel welding, became well established.
Around 1900, A. P. Strohmenger brought a coated
metal electrode in Britain, which had a more stable arc, and
in 1919, alternating current welding was invented by C.J. Holslag, but did not
become popular for another decade.
Resistance welding was developed during the end of the 19th century,
with the first patents going to Elihu Thompson in 1885, and he produced
advances over the next 15 years.

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