Acrylic photo frame injection molding process features

Injection molding is one of the processes in the processing of acrylic frames. What are the characteristics of this process?

Acrylic photo frames have a certain water absorption, their water absorption rate is 0.3-0.4%, and injection molding must be below 0.1%, usually 0.04%. The presence of moisture causes bubbles, gas ray, reduced transparency, and the like in the melt. So dry it. The drying temperature is 80-90 ° C and the time is 3 hours or more.

The mold temperature can be 60 ° C -80 ° C, the diameter of the main channel should match the inner taper, the good angle is 5 ° to 7 °, if you want to injection 4 mm or more acrylic photo frame, the angle should be 7 °, the mainstream diameter is up to 8 To 10mm, the overall length of the gate should not exceed 50mm.

For products with a wall thickness of less than 4 mm, the diameter of the runner should be 6-8 mm; for products with a wall thickness greater than 4 mm, the runner diameter should be 8-12 mm; for the edge, sector and tabs, the depth should be 0.7 to 0.9t (t is the wall thickness of the product), the diameter of the needle gate should be 0.8 to 2mm; the lower viscosity should be smaller.

Common venting holes are 0.05 to 0.07 mm deep and 6 mm wide, and the draft angle is 30'-1° between the cavity portions 35'-1°30°.