Select electrodes based on the steel chemical composition, mechanical properties , crack resistance requirements , taking into account the welded structure, plate thickness , workingCondition , the force , a comprehensive analysis of welding performanceandotherfactors.Ifnecessary,do the welding test , develop appropriate technical measures , and then determine the choice ofElectrode.⒈ carbon steel welding is generally used with corresponding strength grade of steel rod , taking into account the complex structure , plate, stiffness, dynamic load, Weldability poor , generally used in good plasticity , impact toughness, crack resistance good low hydrogen type electrode . There are special requirements for the welding position , theUsing the corresponding specific electrode , such as vertical down welding , welding , etc. bottoming . Can be used to improve the welding efficiency iron powder type electrode .⒉ the weld cooling speed, strength increased, weld cracks easily , and then you can use a low strength than the base metal of the electrode ; carboSteel and low alloy steel welding between dissimilar , generally used with low intensity level corresponding welding of steel and low alloy steel factors to consider ,To use low hydrogen type is appropriate.⒊ for welding of carbon steel , high Cast Iron Electrodes content of the steel , increasing the weld cracking tendency , generally used in low hydrogen type electrode and the use of pre-Heat, cold and other methods , and slow to adapt to the welding process and other measures.⒋ steel weldability is poor , generally the higher Aluminium Welding Rods content , the workpiece Heavy , complex structure, easy to weld cracking , when the multi- cast alloy elements, It is more prominent. Generally used in low hydrogen type electrode and taking preheating, slow cooling methods such as welding , etc. and the corresponding measures .⒌ To ensure the quality of welding , weld the workpiece should be clean , not allowed to have oil, rust , moisture, paint and dirt, etc. , the use of low-Hydrogen type electrode is particularly important.⒍ for low hydrogen electrodes , welding electrodes shall be 350 ℃ baking 1h, and with the drying with the use , or easy to produce pores, slag , cracks and other defectsCellulose electrodes generally do not need baking , if wet, before welding according to the instructions specified temperature baking , but the temperature is too high will destroy electrode welding processEnergy .⒎ welding current specified in the instructions as a reference value , the actual operation should be specific to master, such as workpiece preheating, 5% lower than the normal current ~15% ; vertical and overhead welding welding welding current is small than the level of 10% to 15% ; comparable AC DC when reduced by 10 percent. When using the DC welder , NoteItalian manual provides welding class character , or affect the welding process.⒏ for low hydrogen type electrode generally not repeated baking , to prevent drug skin crisp , shedding