External coating technique of plastic woven bags

The principle of coating is to apply the resin to the base material woven cloth in the molten state. Only the molten resin is applied to the woven fabric and cooled immediately to obtain the two in one woven fabric. If the molten resin film is sandwiched between the woven cloth and paper or plastic film during compounding, and then it is cooled to obtain the three in one woven cloth, the flat fabric can be coated on one side to obtain the sheet cloth, or the cylinder cloth can be coated on both sides to obtain the coated cylinder cloth. Specifically, after heating, the extruder melts the polypropylene material, extrudes it through the die, extrudes and compounds it with the cylindrical plastic woven cloth on the production line, and cools it to form a coated cloth base. After the cloth base passes through the guide and preheating from the unwinding frame to the surface coating, the cloth base is turned 180 degrees through the cross turning frame on the production line, so that the uncoated surface faces up, and then the cloth base passes through the second guide, the second preheating and the second coating to complete the double-sided coating, so as to ensure continuous production without shutdown. During the coating process, if the vehicle is returned for some reason, the corona machine, preheating and cooling roll water valves shall be closed in time. Open them one by one after entering the car. If the woven cloth has serious Ruffle edges, do not put it on the operating surface to correct the deviation, and appropriately increase the unwinding tension. Before the coating material is poured into the mixer, the dust on the outer skin of the packaging bag shall be cleaned first. During mixing, the coating shall be kept clean to avoid dust entering the hopper.