For oxyacetylene welding of lead, the filler metal
slightly carburizing flame; the tip of the inner cone
should just touch the base metal. Do not melt the base
metal any more than is required to give good fusion.
The molten puddle is controlled and distributed by
Keep the end of the welding rod within the protective
manipulating the torch so that the flame moves in a
envelope of the flame, adding the filler metal without
semicircular or V-shaped pattern. Each tiny segment
agitating the molten puddle. Run the weld from one
of the weld is made separately, and the torch is flicked
end of the joint to the other without stopping. After
away at the completion of each semicircular or
welding is completed, cool the part slowly and then
V-shaped movement. Joints are made in thin layers.
remove the remaining traces of flux with warm water.
Filler metal is not added on the first pass, but is added
on subsequent passes. When welding lead or lead
Nickel and High-Nickel Alloys
alloys, wear a respirator of a type approved for
protection against lead fumes. LEAD FUMES ARE
Oxyacetylene welding of nickel and high-nickel
POISONOUS.
alloys is similar to that for copper-nickel alloys. Good
mechanical cleaning of the joint surfaces is essential.
SAFETY PRECAUTIONS
Plain nickel is welded without a flux, but high-nickel
alloys require a special boron-free and borax-free flux
Whether you are welding, torch brazing, flame
in the form of a thin paste. The flux is applied by brush
cutting, or heating with oxyacetylene equipment,
to both sides of the seam, to the top and bottom, and to
certain precautions must be observed to protect
the welding rod. The torch should be adjusted to give
personnel and the structure from injury by fire or
a slightly carburizing flame; the tip selected should be
explosion. The precautions that follow apply
the same size as (or one size larger than) for steel of
specifically to oxyacetylene work. Other safety
the same thickness. Keep the tip of the cone in contact
precautions are listed in chapter 1 of this manual and
with the molten puddle, and keep the welding rod well
in OPNAVINST 5 100.19.
within the protective envelope of the flame at all times.
After the weld is completed, postheat the part and cool
1. CLOTHING: You should use goggles, a
it slowly. Then remove the flux with warm water.
faceplate, respirators, flameproof gloves, jackets,
leggings, and boots, as appropriate. Do not keep any
Lead
type of lighter on your person and do not wear synthetic
clothing.
Oxyacetylene welding of lead requires special
2. CYLINDER SAFETY: You should follow these
tools and special techniques. A flux is not required.
The metal in the joint area must be thoroughly cleaned
safety precautions when working with compressed gas
before welding. This cleaning is accomplished by
cylinders during cutting or welding operations:
shaving the joint surfaces with a scraper and then
-- Place cylinders a safe distance away from the
wire-brushing the metal with a clean stainless steel
actual welding or cutting operations so that
wire brush to remove oxides and foreign matter. The
lap joint is used for practically all oxyacetylene
sparks, hot slag, or flame will not touch them.
welding of lead, except that a square butt joint may be
-- Do not tamper with, or attempt to repair,
used when the welding is done in the flat position.
cylinder valves.
When the lap joint is used, the edges should overlap
each other from 1/2 inch to 2 inches, depending upon
-- Always place fuel-gas cylinders with the valve
the thickness of the lead.
end up. Acetylene cylinders should be stored in
A special lightweight torch is used for the
the vertical position for a minimum of 2 hours
oxyacetylene welding of lead. The gas pressures range
before use to stabilize the gas.
from 1 1/2 to 5 psi. A completely neutral flame must
-- Handle cylinders carefully; avoid rough
be used; the length of the flame should be somewhere
between 1 1/2 to 4 inches, depending upon the gas
handling that could damage cylinders.
pressures that are used. A soft, bushy flame is best for
-- Close cylinder valve and release gas from the
welding lead in the horizontal position and in the flat
regulator before attempting to remove the
position. A more pointed flame gives better results in
regulator from the cylinder valve.
the vertical position and in the overhead position.
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