The
Importance of Low-Hy Rods in a Welding JobLow-hydrogen
welding rods are the backbone of structural welding. Known as "low-hy"
to welders in the field, this versatile electrode is manufactured to contain less
than 0.6% of moisture in the covering and is required by currently acceptable
welding standards and procedures to be stored in an environment that maintains
factory quality dryness. Its low hydrogen content ensures a smooth, strong
weld that is very ductile, making it the welding rod of choice for structural
welding jobs. It
is well known that prior to beginning a structural welding job that low-hydrogen
electrodes must be conditioned properly to avoid damaging defects in the welds.
One of the ways utilized to protect the low-hydrogen coating is to double coat
using a titania layer to help avoid defects when low hydrogen deposits are required.
But problems such as porosity, hydrogen embrittlement, lack of fusion and cracking
can result if standard low hydrogen rods are not stored according to the manufacturer's
specifications. Specifically,
hydrogen can adversely affect a weld and some steels under a variety of conditions.
The primary source for the presence of hydrogen is moisture in the electrode coating
picked up through exposure to the atmosphere. For this reason with any welding
job proper storage, handling and treatment of low hydrogen electrodes is critical
to prevent a defective weld. This is especially important in the construction
and erection of multiple story buildings which rely for their support and inner
structure on welded steel beams. A
defective weld can result in the collapse of a building or during subsequent inspection
rejection of the weld. This requires rebuilding a portion of the metal inner structure
of a skyscraper or other building sometimes at a cost of many millions of dollars.
Welding
electrodes are manufactured to be within acceptable moisture limits consistent
with the type of covering and strength of the weld metal to be used with the electrode.
They are then packaged in a container which has been designed to provide the degree
of moisture protection considered necessary by the industry for the type of covering
involved. A common mistake is opening the container from the wrong end, or tossing
them around which can crack the low hydrogen coating on the welding rods rendering
them useless. With
any welding job It is very important to maintain your rods or electrodes within
a temperature range of 100°F and 300°F. This temperature range has been
determined by the welding industry to be adequate to prevent atmospheric moisture
from entering the welding rod coating and subsequently entering the weld during
the welding process. In
particular, maintaining low-hydrogen electrodes in a dry, consistently heated
environment is a must. Ask any welding professional and they will recommend that
low-hydrogen electrodes be stored in a rod oven. Any other rudimentary method
such as utilizing an old refrigerator or microwave with a 100 watt light bulb
is laughable and is in no way acceptable for today's welding professional.
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