Another incorrect grounding procedure occurs
when the ground is connected to both the ship on
which the generator is located and the ship on
which the welding is being done. In this situation,
part of the welding current returns through the
When grounding welding equipment, always
insulate the negative cable of the generator from the
ship on which the generator is located and run both
the positive and negative leads to the ship where the
welding is being done.
As an additional precaution, make a ship-to-ship
connection with a heavy copper cable. The cable
should be welded or bolted securely to bare metal
on each ship. If properly attached, the copper cable
will prevent most of the welding current from
returning through the water.
Figure 10-5.--Electrode holders.
This is an additional precaution, NOT
a substitute for correct use of the regular
process. This includes various types of stainless
steel, high-tensile steels, and manganese steels.
Electrodes are also available for welding nonferrous
metals and alloys such as aluminum, copper, nickel,
and certain types of bronze and brass, some of
which were originally considered unweldable.
An electrode holder is essentially a clamping
device for holding the electrode securely in any
Electrodes are manufactured for use with either
position. The welding cable passes through the
straight polarity, reverse polarity, or both. They are
hollow, insulated handle of the holder. The
also designed to be used in the different welding
advantage of an insulated holder is that it may be
positions. For example, an E6030 electrode is
touched to any part of the work without danger of
designed for flat welding and is not suitable for
short circuiting. Electrode holders permit quick and
vertical or overhead welding positions. Electrodes
easy change of electrodes.
are available in a variety of diameters ranging from
one-sixteenth to three-eighths inch and in lengths
Electrode holders are made in a number of
generally shorter than the rods used in gas welding.
different sizes and designs (fig. 10-5). Each holder
Standard lengths are 9, 12, 14, and 18 inches. They
is intended for use within a specified range of
are also available in rolls for use in machine
electrode diameters and within a maximum welding
welding. Some of these coatings may produce a
current amperage. A larger holder isrequired when
slag, but it is quite thin and does not act in the same
welding with a machine having a 300-ampere rating
manner as the shielded arc type of electrode slag.
than when welding with a 100-ampere unit. A
holder will overheat if it is smaller than that
Heavy Coated Electrodes
specified for use with a particular amperage.
The surface of heavy coated electrodes is
comparatively thick. These coatings have been
designed to improve the physical properties of the
Electrodes are manufactured in a variety of
weld. They also control arc stability and, as a result,
metals and are available for use with any alloy that
increase the speed and ease of welding in the
is classed as weldable by the electric arc-welding
vertical and overhead positions. These electrodes