sections of cast iron. View D shows the reciprocating
TORCH MOVEMENTS.--For most oxyacety-
(or back and forth) torch movement that is most effec-
lene cutting, the torch is moved steadily forward along
tive for cutting stainless steels.
the line of cut, as shown in view A of figure 8-23.
Metals that are difficult to cut often require special
FLUXES.--Although fluxes are not used for most
torch movements. For example, the oscillating move-
oxyacetylene cutting, they are used for cutting
ment, shown in view B of figure 8-23, is suitable for
stainless steels, chromium irons, and other metals that
cutting thin sections of cast iron; view C shows the
are hard to cut. Fluxes used for cutting are nonmetallic
oscillating movement that is best for cutting heavier
compounds in powder form. As the powdered flux is
injected into the kerf, it reacts chemically with the
oxides, which have a higher melting point than the base
metal. The result of this chemical reaction is a slag that
melts at a lower temperature. The stream of cutting
oxygen washes the molten slag out of the cut and
exposes the base metal to the cutting action of the
oxygen.
Fluxes are introduced into the cut by means of an
attachment to the standard cutting torch. The
attachment, shown in figure 8-24, consists of a canister
for holding the flux, a length of air hose, and a copper
tube that is secured to the cutting torch with clamps.
Air pressure forces the powdered flux into the kerf; the
stream of cutting oxygen carries the flux deeper into
the kerf.
Judging the Quality of Oxyacetylene Cuts
To know how good a job of cutting you are doing,
you must know what constitutes a good oxyacetylene
torch cut. In general, the quality of an oxyacetylene cut
is judged by (1) the shape and length of the drag lines,
(2) the smoothness of the sides, (3) the sharpness of
Figure 8-23.--Manipulation of the oxyacetylene cutting torch.
Figure 8-24.--Flux cutting attachment.
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