Except for rod diameter, the welding rod selected
drills or other sharp instruments. These devices may
is determined by specification on the basis of the
enlarge or scratch the tip opening and greatly reduce
metals being joined. These specifications may be
the efficiency of the torch tip.
either federal or military. This means that they apply
to all federal agencies and the military establishment.
HOSE
Filler metals are presently covered by one or both of
these specifications.
The hose used to make the connection between the
torch and the regulators is strong, nonporous, and
Many different types of rods are manufactured for
flexible and light enough to make torch movements
welding ferrous and nonferrous metals. In general,
easy. It is made to withstand high internal pressures,
shipboard welding shops stock only a few basic types
and the rubber used in its manufacture is specially
that are suitable for use in all welding positions. These
treated to remove sulfur to avoid the danger of
basic types are known as general-purpose rods. One
spontaneous combustion. Welding hose is available in
such general-purpose rod that will be found in any
various sizes, depending upon the size of work for
Navy welding shop is a rod suitable for oxyacetylene
welding of low-carbon steel. Such a rod is class 1, type
which it is intended. Hose used for light work is 3/16
A, as specified in AWS-A5.2-88. The same specifica-
or 1/4 inch in diameter and has one or two plies of
tion covers welding rods (class II) for use on cast iron.
fabric. For heavy-duty welding and cutting operations,
the hose will have an inside diameter of 1/4 or
Rods for gas welding on other common materials
5/16 inch and three to five plies of fabric. Single hose
are covered by other specifications. At the time this
may be ordered in various lengths up to 600 feet on a
manual was written, the following specifications ap-
spool. Some manufacturers make a double hose that
plied: copper-base alloys, MIL-R-19631B; corrosion-
conforms to the same general specifications. The hoses
resisting and heat-resisting steel, MIL-R-5031B, class
used for acetylene and oxygen are the same in grade,
5; nickel-base alloys, including Monel, QQ-R-571C;
but they differ in color and have different types of
threads on the hose fittings. The oxygen hose is
GREEN and the acetylene hose is RED. For added
SETTING UP THE EQUIPMENT
protection against mixing of the hoses during
The procedure for setting up oxyacetylene
connection, the oxygen hose has right-hand threads
equipment is as follows:
and the acetylene hose has left-hand threads. The
acetylene fittings also have a notch that goes around
1. Secure the cylinders so that they cannot be
the circumference of the fittings for an additional
upset. Ensure that the acetylene cylinders have been in
identification factor.
the vertical position a minimum of 2 hours before
removing the protective caps.
WELDING RODS
2. Crack the cylinder valves slightly to blow out
any dirt that may be in the valves. Close the valves.
The term welding rod refers to a filler metal, in
Check for grease and oil on or near the valves and
wire or rod form, used in gas welding and brazing
fittings of the cylinders. Wipe the connections with a
processes and in certain electric welding processes
clean cloth.
(tungsten inert-gas) in which the filler metal is not a
part of the electric circuit. A welding rod serves only
one purpose--it supplies filler metal to the joint.
As a rule, rods are uncoated except for a thin film
CAUTION
resulting from the manufacturing process. Welding
rods for steel are often copper-coated to protect them
Never crack gas cylinder valves toward
an individual and always wear safety glasses.
from corrosion during storage. Most rods are furnished
in 36-inch lengths and a wide variety of diameters,
ranging from 1/32 to 3/8 inch. Rods for welding cast
iron vary from 12 to 24 inches in length and are
3. Connect the acetylene pressure regulator to the
acetylene cylinder and the oxygen pressure regulator to
frequently square rather than round in cross section.
the oxygen cylinder. Using the appropriate wrench
The rod diameter selected for a given job is governed
provided with the equipment, tighten the connecting
by the thickness of the metals being joined.
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