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Introduction to gas cutting.

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The thermal cutting equipment consists of two
cylinders, one being oxygen, the other being

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fuel gas, the fuel and the oxygen being
controlled by a regulator which are also

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attached to the hoses via a flashback
arrester.

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And the houses then connect to the cutting
torch.

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Before cutting operations can commence, the
equipment must be set, and this is done by

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first turning on the cylinders half a turn
each.

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And then set the regulator pressures for the
cutting operation.

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The operating pressures are normally set on
a ratio of one to 10, with the oxygen being

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set to around 30 PSI and the propane being set
to around three PSI.

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And once the pressures have been set, the
torch can be lit.

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And this is done by using a flint gun.

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The flame must be then set to the correct
cutting flame.

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The correct cutting flame is called a
neutral flame.

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The other two types of flame, which can be
used for cutting operations, are called the

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carborizing flame and the oxidizing flame.

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Once the neutral flame has been achieved,
the cutting operation can commence.

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To begin the cut, the operator needs to allow for
the metal to heat up to a bright cherry red,

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which is approximately nine hundred
degrees centigrade once this temperature has

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been achieved. The operator can then
initiate a jet stream, which will rapidly

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oxidize the material and start the cut.

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This brings the temperature up to around
fifteen hundred degrees centigrade.

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The operator can then begin to move smoothly
and steadily around the material, allowing

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the cut to take place.

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It is important to move at the correct pace.

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If the operator moves too quickly, the cuts
won't penetrate the material.

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If the operator moves too slowly, the
material may actually melt too much and fill

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in the cut that has already been made.

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Once the cut is complete, allow the
material to cool down before inspection.

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In this case, the operator has doused the
material and it is safe to inspect.

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The back of the material may contain dross
which would need to be removed.

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The causes of dross may be incorrect pressure
settings or the operator may have moved too

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slow, which would allow for a buildup of
molten material on the back of the material

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with optimal pressure settings and a smooth,
steady rate of cutting which comes from

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practice and experience.

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The final result will be a smooth, clean
cut.