In addition, when the basic electrode is DCEP welding, the hydrogen content is lower than that of DCEN?
Because of the alkaline electrode contains a lot of calcium fluoride (CaF), the decomposition of fluorine in the arc under the ionization potential of fluorine is high, not easily ionized, and the outermost layer of fluorine has seven electrons, cannot lose electrons to become positive ions, but easy to get electrons becomes negatively charged, if the answer is that will, fluorine ion mass to welding pool movement, so will increase caused by splash, arc burning instability. The reverse, however, and when using the reverse connection, positive ion electron in hydrogen, in the molten pool is formed on the surface of HF, the surface can be greatly reduced in welding seam hydrogen.
The welding process is all on the increase of hydrogen from hydrogen weld, welding material, workpiece oil rust and water vapor in the air, so the general basic low hydrogen welding welding before drying;When AC welding of basic electrode, the arc is unstable, and the DC reverse connection is more stable than the direct current connection. Therefore, the welding torch is low and the welding arc is relatively stable;DC electric arc welding, welding welder with positive output, torch (holder) cathode is connected with the output end of the wiring method, called "connect law" also known as positive;DC electric arc welding, welding welder with negative output, torch (holder) connection is connected with the output end of the cathode, called "reverse method" is also known as reverse polarity.When welding with a DC arc welding machine, the welding heat obtained by the direct welding method is high.In the MIG welding, weld reverse DC deep shallow, weld and weld pool is flat, is conducive to the gas pool in the liquid metal, and the arc than is then stable, the protective effect of welding material of gas production slag is better.
The key point is that the welding rod can use acid and basic electrode, AC only use acid electrode, and arc welding with basic welding rod. The quality of DC welding and arc stability are better than those of AC welding. If it's an electric welder, it's AC
