How To Look Up Tungsten Electrode Products
Tungsten electrodes are used in TIG/GTAW
welding and in plasma
arc welding. It has to be bought with
care. There are many companies which manufacture tungsten
electrodes. Among all the pure metals, tungsten has
the highest melting temperature. A tungsten electrode
that is of high quality will arc easily, have an improved
arc time and result in a good quality weld with minimum
contamination. The tungsten electrode should have
very small grain structure and allowing for better
migration of oxides to the tip. You can have clean
finish or ground finish tungsten electrodes. Clean
finish tungsten electrodes are the ones that have
been chemically cleaned. Ground finish tungsten electrodes
are the ones that have been ground to a uniform shape
with a polished surface. This makes them right for
optimal heat conduction. The tungsten electrode
should meet the ISO6848 and AWS A5.12 standards.
There has been a lot of improvement in the manufacture of tungsten electrodes.
The addition of oxides to pure tungsten has resulted in tungsten alloys
that give the same level of emission as pure alloys but at a much lower
temperature. This helps in improving the arc time of the electrode and
the arc stability.
It is best to choose a tungsten electrode that performs well with
all metals and all welding power sources for hand held welding. For
all types of automated welding operations, it is best to choose the
type of tungsten electrode that suits it, through testing it.
Each oxide has a different physical characteristic. This affects the
work of the tungsten electrode. This is color coded and shows us with
which oxide it is mixed. There is no standard for these color codes
and can vary in U.S., Europe and Japan.
After choosing the blend of oxide with tungsten to suit your needs,
you should choose the diameter of the tungsten electrode. They are available
in packages of ten in a variety of standard diameters. Choosing the
diameter of the tungsten electrode is important as it will affect the
welding performance and welding bead shape.
In welding with tungsten, an arc of electricity is created between
the tungsten electrode and the material to be welded. A filler metal
is fed into the molten metal pool while welding. This process requires
an air or water cooled torch to keep the tungsten electrode in place
as it is connected to the TIG welder. The welding equipment should adhere to the norms
set by the government and have GTAW in quality standards.
The advantage of Tungsten welding
is that it welds of high quality can be made with
or without filling, good control of heat and having
low distortion. The problems faced are that of an
erratic arc, high electrode consumption and leading
to porosity of the weld.
Different types of tungsten electrodes are
used for different purposes. Pure tungsten electrodes
are used for general use and are classified as WP
or EWP. Cerium oxide and lanthanum oxide help in improving
arc stability. They also help in starting easily and
decreases burn-off. Thorium oxide is especially designed
for DC operations. It can also handle high temperatures.
Since it is radioactive and inhalation of the fumes
while grinding thorium can be hazardous to health.
Thorium electrodes can be replaced with greater concentration
of lanthanum electrodes. Zirconium electrodes increase
current capacity, increases electrode life, improves
arc stability and starting. Manufacturers can also
manufacture other tungsten alloys that will be with
specific metal additions which will follow EWG classification
under the AWS system.
So you can search the internet or go to the specific shops that deal
in tungsten electrodes and get the suitable product for your needs.
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