BUG-O Systems Flame Cutting - Manual (Page 7)

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INTRODUCTION
GAS CUTTING OF FERROUS
(CARBON STEEL) METALS
Gas cutting is a process of preheating carbon steel to
its combustion temperature, then burning it rapidly by
means of a regulated jet of oxygen. A cutting torch is
used for this operation.
The process is primarily a chemical one. It is based
on the chemical relationship of oxygen to iron metals
that have been heated to a temperature of 1400° to
1600° F (760° to 871° C). Only the metal within the
direct path of the oxygen jet is affected.
In cutting, a “kerf” is formed. This is a narrow slit having
uniformly smooth and parallel walls. A skilled workman
using a BUG-O and a machine cutting torch can
maintain the following tolerances with respect to
squareness and straight alignment of the cut surface:
1/32nd of an inch (.79mm) on plate thickness up to 4
inches (100mm) and 1/16th of an inch (1.58mm) on
plate thicknesses from 4 to 12 inches (100 to 300 mm).
In actual gas cutting, the iron or steel removed from
the “kerf” is not entirely burned or consumed by the
oxygen. About 30 to 40 percent of the metal is washed
out of the cut as unconsumed or metallic iron due to
the eroding effect of the oxygen jet.
Flame Cutting Handbook.p65 5/9/2007, 8:06 AM 7