Page 25 - Welding Robots Technology, System Issues, and Applications

Introduction and Overview

Avery Adams, founded the American Welding Society, a nonprofit organization
dedicated to the advancement of welding and allied processes. 9

Alternating current, invented in 1882 by Nicola Tesla, was applied to welding for
the first time by C.J. Holslag in 1919. However it did not became popular, for
welding, until the 1930s when the heavy-coated electrodes become generally used.

In 1920, automatic welding was invented by P.O. Nobel of the General Electric
Company. It was used to build up worn motor shafts, worn crane wheels, and rear
axle housings for the automobile industry. This process utilized bare electrode wire
operated on direct current and utilized arc voltage as the basis of regulating the
feed rate.

During the 1920s, various types of welding electrodes were developed, with a
considerable controversy about the advantage of the heavy-coated rods vs light-
coated rods. By 1930, covered electrodes were widely used. Welding codes
appeared which required higher-quality weld metal, which increased the use of
covered electrodes.

Also during the 1920s there was considerable research in trying to shield the arc
and weld area by externally applied gases. The atmosphere of oxygen and nitrogen
in contact with the molten weld metal caused brittle and sometime porous welds.
Research work was done utilizing gas shielding techniques. Alexander and
Langmuir did some exploratory work in chambers using hydrogen as a welding
atmosphere. They first utilized two electrodes of carbon, but changed later to
tungsten. The hydrogen was also changed to atomic hydrogen near the arc, because
the flame produced was more intense than the molecular form produced flame, and
as intense as an oxyacetylene flame. This then became known as the atomic
hydrogen welding process. Atomic hydrogen never became popular but was used
during the 1930s and 1940s for special applications of welding and later on for
welding of tool steels.

H.M. Hobart and P.K. Devers were doing similar work but using atmospheres of
argon and helium. Their patents (1926) were the predecessors of the gas tungsten
arc welding process, because they showed how to carry out arc welding utilizing
gas supplied around the arc. They also showed welding with a concentric nozzle
and with the electrode being fed as a wire through the nozzle. This was the
predecessor of the gas metal arc welding process (GMAW), which was developed
only 20 years later.

Stud welding was developed in 1930 at the New York Navy Yard, specifically for
attaching wood decking over a metal surface. Stud welding became popular in the
shipbuilding and construction industries.

The automatic process that became popular was the submerged arc welding
process. This "under powder" or smothered arc welding process was developed by
the National Tube Company for a pipe mill at McKeesport, Pennsylvania. It was