Type of one color coating plate
Good adhesion, rich color, wide range in molding and outdoor durability, medium chemical resistance, low cost.
Silicone modified polyester
Namely (SMP), the coating has good hardness, wear resistance and heat resistance, as well as good external durability and anti pulverization, gloss retention, general flexibility and medium cost.
High durability polyester
Namely (HDP), excellent color retention and UV resistance, excellent outdoor durability and anti pulverization, good film adhesion, rich color, excellent cost performance.
Color steel plate manufacturer
Before welding, the second printing color coated plate is easy to produce cracks. Why does this happen? So we need to understand the causes of the cracks first to find out the causes, so as to prevent accidents.
Under the action of arc heat, the zinc layer near the groove of printing color coated plate produces oxidation (forming ZnO) and evaporation, and volatilizes white smoke and steam, so it is easy to cause pores in the weld. The higher the welding current is, the more serious the zinc evaporation is and the more sensitive the porosity is. When titanium and calcium titanium electrodes are used for welding, it is not easy to produce pores in the middle current range. However, when cellulose electrode and low hydrogen electrode are used for welding, pores are easy to be produced under low current and high current. In addition, the electrode angle shall be controlled within 30 ° - 70 ° as far as possible.
Secondly, when arc welding is used for printing color coating plate, the zinc layer near the molten pool is oxidized to ZnO under the action of arc heat and evaporates, forming a large amount of smoke and dust. Therefore, good ventilation measures must be taken. In the same welding specification, the amount of smoke produced by titanium oxide electrode is lower than that of low hydrogen electrode.
Finally, when the welding current of the color coated galvanized sheet is small, the ZnO formed in the heating process is not easy to escape, which is easy to cause ZnO slag inclusion. The melting point of ZnO is 1800 ℃. The large ZnO slag inclusions have a very adverse effect on the weld plasticity. When titanium oxide electrode is used, ZnO is fine and evenly distributed, which has little effect on plasticity and tensile strength. When cellulose electrode or hydrogen electrode is used, the ZnO in the weld is larger and more, and the weld performance is poor.