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2. All of the following improvements of the welding process refer to the 20
th
century EXEPT
a) covered electrode
b) electric arc
c) shielding gas
d) automatic welding
3. The invention attributed to a Russian inventor Benardos is
a) carbon electrode
b) acetylene
c) resistance welding
d) alternating current welding
4. The latest welding process having been introduced is
a) electrogas welding
b) laser beam welding
c) flux-cored arc welding
d) electroslag welding
3 Read the text and check your answers in the previous exercise.
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
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