Electrode Angle
The angle that the electrode makes with the
work is im portant to ensure a smooth, even
transfer of metal. When welding in down
hand, fil let, horizontal or overhead the
angle of the electrode is generally between
5and 15 degrees towards the direction of
travel. When vertical up welding the angle
of the electrode should be between 80 and
90 degrees to the work piece.
Travel Speed
The electrode should be moved along in the
direction of the joint being welded at a
speed that wil l give the size of run required.
At the same time, the electrode is fed
downwards to keep the correct arc length at
all times. Excessive travel speeds lead to
poor fusion, lack of penetration etc, while
too slow a rate of travel wil l frequently
lead to arc instability,slag inclusions and
poor mechanical properties.
Material and Joint Preparation
The material to be welded should be clean
and free of any moisture, paint, oil, grease,
mill scale, rust or any other material that
will hinder the arc and contaminate the
weld material. Joint preparation will
depend on the method used include
sawing, punching, shearing, machining,
flame cutting and others. In all cases edges
should be clean and free of any
contaminates. The type of joint will be
determined by the chosen application.
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