manufacturer's system. In general, the smaller the
protect the eyes from sparks and molten metal.
number, the smaller the tip orifice.
Regardless of the shade of lens used, goggles should be
protected by a clear cover glass. The welding operator
No matter what type or size tip you select, the tip
should select the shade or density of color that is best
must be kept clean. Quite often the orifice becomes
suited for his/her particular work. The desired lens is
clogged with slag. When this happens, the flame will
the darkest shade that will show a clear definition of the
not burn properly. Inspect the tip before you use it. If
work without eyestrain. Goggles should fit closely
the passage is obstructed, you can clear it with wire tip
around the eyes, and should be worn at all times during
cleaners of the proper diameter, or with soft copper
welding and cutting operations. Special goggles, using
wire. Tips should not be cleaned with machinist's drills
standard lenses, are available for use with spectacles.
or other sharp instruments. These devices may enlarge
or scratch the tip opening and greatly reduce the
WELDING (FILLER) RODS.--The use of the
efficiency of the torch tip.
proper type of filler rod is very important in
oxyacetylene welding operations. This material not
HOSE.--The hose used to make the connection
only adds reinforcement to the weld area, but also adds
between the torch and the regulators is strong,
desired properties to the finished weld. By selecting the
nonporous, light, and flexible to make the torch
proper type of rod, either tensile strength or ductility
movements easy. It is made to withstand high internal
can be secured in a weld. Similarly, rods can be selected
pressures, and the rubber used in its manufacture is
that will help retain the desired amount of corrosion
chemically treated to remove sulfur to avoid the danger
resistance. In some cases, a suitable rod with a lower
of spontaneous combustion.
melting point will eliminate possible cracks from
The oxygen hose is GREEN, and the acetylene
expansion and contraction.
hose is RED. The hose is a rubber tube with braided or
Welding rods are classified as ferrous and
wrapped cotton or rayon reinforcements and a rubber
nonferrous. The ferrous rods include carbon and alloy
covering. The hoses have connections at each end so
steel rods as well as cast iron rods. Nonferrous rods
they can be connected to their respective regulator
include brazing and bronze rods, aluminum and
outlet and torch inlet connections. To prevent a
aluminum alloy rods, magnesium and magnesium alloy
dangerous interchange of acetylene and oxygen hoses,
rods, copper rods, and silver rods. The diameter of the
all threaded fittings used for the acetylene hookup are
rod used is governed by the thickness of the metals
left-handed threads, and all threaded fittings for oxygen
being joined. If the rod is too small, it will not conduct
hookup are right-handed threads. The hoses are
heat away from the puddle rapidly enough, and a
obtainable as a single hose for each gas or with the
burned weld will result. A rod that is too large will chill
hoses bonded together along their length under a
the puddle. As in selecting the proper size welding
common outer rubber jacket. This type prevents the
torch tip, experience will enable the welder to select the
hose from kinking or becoming entangled during the
proper diameter welding rod.
welding operation.
Welding Flames
LIGHTERS.--A flint lighter is provided for
igniting the torch. The lighter consist of a file-shaped
The welding flame is classified as neutral,
piece of steel, usually recessed in a cuplike device, and
carburizing, or oxidizing. Each type of flame has its
a piece of flint that can be drawn across the steel, which
own special function. The operator can adjust the torch
produces the sparks required to light the torch.
to produce the type of flame best suited for the job at
hand.
WARNING
The neutral flame, in which a balanced mixture of
oxygen and acetylene is burned, is used for most
Matches should never be used to ignite a torch;
welding operations. The oxidizing flame, in which an
their length requires bringing the hand too close to
excess of oxygen is burned, is used for welding bronze
the tip to ignite the gas. Accumulated gas may
or fusing brass and bronze. The carburizing flame, in
envelope the hand and, when ignited, cause a severe
which an excess of acetylene is burned, is used when
burn.
welding nickel alloys.
GOGGLES.--Welding goggles are fitted with
NEUTRAL FLAME.--The neutral flame does
colored lenses to keep out heat and light rays and to
not alter the composition of the base metal to any great
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