Jasic TIG315PACDC(E202), Operator'S Manual

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5) Electrode manipulation
The electrode manipulation actually is a resultant movement in which the electrode simultaneously moves in
three basic directions: the electrode gradually moves along the welding direction; the electrode gradually moves
toward the weld crater; and the electrode transversely swings. (See Fig.13.4) Electrode should be correctly
manipulated in three movement directions after arc is ignited. In butt welding and flat welding, the most
important is to control the following three aspects: welding angle, arc length and welding speed.
(1)welding angle: the electrode should be inclined in 70
～
80º forwards. (See Fig.13.5)
(2)Arc length: the proper arc length is equal to the diameter of electrode in general.
(3)Welding speed: proper welding speed should make the crater width of the weld bead about twice the diameter
of the electrode, and the surface of the weld bead should be flat with fine ripples. If the welding speed is too high,
and the weld bead is narrow and high, the ripples are rough, and the fusion is not well implemented. If the
welding speed is too low, the crater width is excessive, and the workpiece is easy to be burned through. Besides,
current should be proper, electrode should be aligned, arc should be low, and welding speed should not be too
high and should be kept uniform during the whole welding process.
1. Feed down
2. Move along the welding direction
3. Lateral swing
Three basic movement directions of electrode
Angles of electrode in flat welding
6.Arc extinguishing
Arc extinguishing is unavoidable during welding. Poor arc extinguishing may bring shallow weld crater and
poor density and strength of weld metal by which cracks, air holes, slag inclusion and shortage the like are easy to
be produced. Gradually pull the end of the electrode to the groove and raise the arc when extinguishing arc, in
order to narrow the weld crater and reduce the metal and heat. Thus, defects such as cracks and air holes can be
avoided. Pile up the weld metal of the crater to make the weld crater sufficiently transferred. Then, remove the
excessive part after welding. The operation modes of arc extinguishing are shown in the figure.