Electrode arc welding swing method

1、 Welding arc striking

Arc striking is the process of igniting welding arc at the beginning of arc welding.

Arc striking methods include the following two types:

1.Non contact arc ignition: high frequency voltage is used to conduct gas between electrode and weldment to generate arc, which is rarely used in shielded metal arc welding.

2.Contact arc striking: short circuit the weldment and electrode, and then pull the electrode for arc striking.

According to different operation methods, it can be divided into the following two types:

(1) Percussion method: the electrode is in vertical contact with the surface of the weldment. When the end of the electrode contacts the surface of the weldment, quickly lift the electrode and keep a certain distance to ignite the arc.

(2) Scratch method: align the end of the welding rod with the weldment, scratch on the surface of the weldment, and keep the distance between the end of the welding rod and the welding surface at 2 ~ 4mm before the metal begins to melt a lot, so that the arc can burn stably.

If the electrode is stuck on the weldment, it can be separated from the weldment only by shaking the electrode left and right for several times. If the electrode can not be separated from the weldment at this time, immediately loosen the welding tongs, disconnect the welding circuit, and remove the electrode after it is slightly cold.

3.Precautions during arc striking

Due to the low temperature and shallow penetration at the arc striking end, it is easy to have incomplete penetration. When the acid electrode is used for arc striking, lengthen the arc to preheat the groove, and then lower the arc for welding. The alkaline electrode does not use the acid electrode for arc striking, nor does it directly strike the arc. After the groove is used for arc striking, pull back the welding end and lower the arc for welding.

2、 Yuntiao

The movement of welding rod is a variety of actions of welding rod to the weld in the welding process.

The basic movement of the strip

After the electrode is fed into the molten pool along the axis, the arc length can remain unchanged, so the speed of electrode feeding into the molten pool is equal to the speed of electrode melting. If the melting speed of the electrode is greater than the feeding speed, the arc length will increase, resulting in arc breaking. If the feeding speed of the electrode is fast, the arc length will shorten, and the electrode will contact the weldment, resulting in short circuit and arc extinction.

The welding rod moves in the longitudinal direction without welding direction, and the deposited metal and the base metal form a weld. The function of the welding rod lateral swing is to obtain a certain width of weld, so as to ensure the weld fusion is good. The swing range shall be determined according to the width of the weld and the diameter of the welding rod. Only if the transverse swing is even, the required width and speed of the weld can be obtained, The normal weld width is generally not more than 2-5 times of the electrode diameter.