Storing and Re-Drying Tungsten Electrodes
Tungsten electrodes should be stored properly for use in welding.
There are procedures and rules for storing and re-drying tungsten electrodes
and other welding material. There are some precautions that also need
to be taken to keep them properly for getting the best results.
There are certain welding materials such as tungsten electrodes that
can be affected by moisture. They should be stored in a dry, well ventilated
store. Special rooms or cabinets have to be built for storing these
materials at the welding material control room and at the issue centers
in all factories etc. A proper temperature should be maintained in these
rooms. The temperature should generally be maintained at least 10 degrees
C above ambient so that the relative humidity is kept below 60%.
When the welding material such as tungsten electrodes has to be sent
to various construction sites for welding purposes, welding stations
should be set up. These welding stations should have ovens operating
at a temperature between 130 degrees C to 150 degrees C so that low
hydrogen electrodes can be stored properly.
All the containers that are available in the materials control and
issue centers should be stored properly. The unopened containers in
the storage room should not have any contact with the ground and the
materials should be stacked in such a way that the materials are not
damaged. Filler rods and wires should also be stored exactly as the
electrodes are stored and they should be kept in protective wrappers
until they have to be used.
When the electrodes are issued for use, they should be checked for
moisture content of the cover and then only issued. If there is moisture
content, they should be re-dried. When low alloy/low hydrogen electrodes
are issued, they should be issued in welder’s ‘hot boxes’.
These will have a distinct number and the electrode type, so that they
do not get mixed up. The welding material will be given
only when authorized and the date and time of issue will be noted. If
there is any unused material that is returned to the material control
center store, it will be segregated for baking and reissue. The electrodes
can only be re-dried a maximum of 2x. If there is any partly used or
damaged electrode belonging to this category, it will be discarded.
There should be only one type of electrode in the hot box and this should
be opened only to take out the electrode.
There are certain rules to be followed for re-drying certain types of
electrodes. This should generally according to the instructions given
by the manufacturer. If there are any changes, the welding Superintendent
in that store will give the final decision.
Cellulose electrodes should be stored dry and they should not be re-heated.
Rutile electrodes should be stored dry. If they become damp, they should
be dried for one hour at 120 degrees C before using it.
Carbon steel and hydrogen alloys should be used directly – hot from
the welder’s box. They should be treated only if affected
by moisture.
Some electrodes require special treatment and should be followed for
storing, baking and issue.
Storing the electrodes properly is the main thing. Only some electrodes,
if they contain moisture, have to be re-dried. To obtain the best results
when welding and using tungsten electrodes, it would be best to follow
all the procedures for storing and re-drying them.
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