ARCAIR SLICE PACKAGE, Инструкция по безопасности и эксплуатации

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SLICE EXOTHERMIC CUTTING EQUIPMENT
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SECTION 3:
PROCESS FUNDAMENTALS
The SLICE Exothermic Cutting process uses an exothermic chemical reaction that burns, melts or vapor-
izes most materials. The reaction begins with an electrical arc or alternate energy source that causes a
steel cutting rod to burn. Oxygen flows through the center of the rod.
Because of the rod’s design, the burning makes excess heat (“exo - thermic”) which cuts the work-
piece. Once started, the burn will continue as long as oxygen flows through the rod. The heat created
melts the material being cut. The velocity of oxygen through the rod blows the molten material away,
creating the kerf or cut line.
This arc ignition process led to invention of the oxy-arc torch and design of equipment for underwater
construction and salvage.
The electrical arc that starts the burn can be from a welding power source that delivers at least 100
amps, a 12-volt lead acid or similar low-impedance battery. The cutting process can run without power,
using the heat of the reaction only, or with power, cutting with an electrical arc from a welding power
source providing more heat.
HISTORY
The exothermic cutting rod is a small oxygen lance. A prime example of the combustion triangle is one
side being fuel (the steel lance); the oxygen source (pure oxygen being forced through the lance); the
heat of combustion (some external source of heat). However, when the lance pierces a slag puddle, the
puddle becomes the source of heat until the lance is withdrawn, at which time burning stops.
In 1888, a published paper described passing oxygen through a steel tube and heating the tube to a
bright red. Heat resulted. In 1901, Ernst Henner filed a German patent on an early oxygen lance made
of two concentric tubes. In 1902, documentation shows that the oxygen lance replaced oil and gas
torches for opening furnace taps in steel blast furnaces. The oxygen lance has since been used to cut
rocks and concrete structures. An example is cutting up reinforced concrete structures such as bunker
emplacements and tank traps built in Europe during World War II.
An ideal way to start the lance, workers found, was to use a welding power source on conductive
material to strike an arc and start the burn. This process worked well in construction, even in mud and
water.
Around 1940, the burning bar or exothermic lance was first marketed as a cutting tool. A flexible ver-
sion made of an insulated cable was introduced around 1960. Not until the early 1980’s were smaller
burning bars designed for hand torch use, above and below water. A one-piece unit now allows for
adequate rod surface exposure to an oxygen supply for exothermic cutting. Arcair, an ESAB brand, is a
world leader in metal removal and cutting and sells this exothermic cutting equipment under the trade
name Arcair SLICE.
PROCESS FUNDAMENTALS