faq
1 problems: continuous linear stripes along the machine direction
may be the film processing waste or lip, lip membrane surface deposition, or a trace and other auxiliary drive on
the polishing die lip surface, to eliminate mold processing residue on the head; using copper knife scraping or disassembling cleaning method to remove die die lip dirt on the surface; polishing roller
2 problems: the continuous along the edge of the scars
may be the resin raw material moisture
feeding before first dry resin
3 problem: perpendicular to the machine direction.
the film in the melt cooling roller has no sufficient cooling and sticking phenomenon, or equipment caused by mechanical vibration
reduce the cooling roller and the guide roller temperature, to prevent sticking film; reduce the resin temperature to prevent vibration of the machine;
4 problem: oval streamline
melt mixing
the use of screw mixing efficiency; material mixing head installed in the screw front; the high back pressure
5 problems: the entire surface is covered with
casting roll temperature is too high, the extrusion process is not correct, or improper selection of raw materials
raise the feeding section and compression section temperature; take measures to improve the extruder mixing capacity; the use of wide molecular weight distribution of the resin casting roller; lower temperature; the selection of raw materials suitable
6 problem: orange peel surface
lip-length convergence angle is too large or not
the convergence angle of modified die head for a longer length and smaller die lip
7 problems: excessive fog film
the high temperature cooling roller, the selection of raw materials is not correct
or
8 problem: stiffness difference
low temperature of the cooling roll, improper selection of resin
raise the temperature of the cooling roller; lower processing temperature; resin isomer content is high; and in the additive formulation in nucleating agent
9 problems: uneven thickness
die lip gap is not uniform, and the surface of the core layer melt flow ratio imbalance, or improper selection of raw materials
detection and die gap adjusted to obtain a uniform gap; detecting and regulating the flow and the extension, smooth rotation; for multilayer coextrusion, balancing the melt flow of surface layer and core layer than the resin; using the wide molecular weight distribution
