The electrode is formed by the two parts of the metal cores and coating, the cores of the main role is as an electrode and filler metals; coating is mainly arc stability, protection, deoxidization, alloying and improve the welding process.
The basic principle for the selection of electrode:
1 intensity principle: choice of electrode base material with the same strength grade. Generally used for welding of low carbon steel and low alloy steel.
2 with the same composition principle, namely selection and chemical composition of the parent material in the same or similar electrode. For welding of heat resistant steel, stainless steel and other metal materials.
3 anti crack principle, selection of basic electrode with good crack resistance, so as to avoid joint cracks in the welding process and use. General for welding structure dynamic load bearing stiffness, complex shape and use.
4. Anti blowhole principle, by welding process conditions, such as welding joints of oil and rust cleaning inconvenience should be selection of stomatal resistance and strong acid electrode, so as to avoid the welding process in gas retention in the weld and the formation of pores.
5 low cost principle, in order to meet the requirements of the use of technology, to the selection of good performance, low cost and high efficiency of the electrode.