Shielded metal arc welding is a manual arc welding process that uses a
consumable electrode coated in flux to lay the weld. An electric
current (either alternating current or direct current from a welding
power supply) is used to form an electric arc between the electrode
and the metals to be joined. As the weld is laid, the flux coating of
the electrode disintegrates, giving off vapors that serve as a
shielding gas and providing a layer of slag, both of which protect the
weld area from atmospheric contamination. Because of the versatility
of the process and the simplicity of its equipment and operation,
shielded metal arc welding is one of world's most popular welding
processes. It dominates other welding processes in the maintenance and
repair industry, and though flux-cored arc welding is growing in
popularity, it continues to be used extensively in the construction of
steel structures and in industrial fabrication. The process is used
primarily to weld iron and steels (including stainless steel), but
nickel and copper alloys can also be welded.
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Today's selected anniversaries:
Louis IX of France dispatched Andrew of Longjumeau as his ambassador
to the Mongols.
Lt. Stephen Decatur led a raid to destroy the captured USS
Philadelphia in Tripoli of the Barbary States, denying her use to the
enemy in the First Barbary War.
Gallaudet University, the world's only university for
hearing-impaired students, was established in Washington, D.C..
Howard Carter unsealed the burial chamber of Tutankhamun, a Pharaoh of
the Eighteenth Dynasty of Egypt.
The first computer bulletin board system, CBBS, was established by
Ward Christensen during a blizzard in Chicago, Illinois.
Wikiquote of the day:
"Politics, as a practice, whatever its professions, has always been
the systematic organization of hatreds." -- Henry Adams