Plastic mold injection product defects and solutions

Plastic mold injection products refer to plastics that are heated, plasticized and melted by a plastic mold injection molding machine, and then injected into the cavity of the molding mold for molding. After cooling and cooling, the melt is solidified and then demolded and injected.

The reasons for the defects of plastic mold injection products are: injection molding dissatisfaction, dents, fusion seams, material flow, poor gloss, pores, black spots, overflow, warpage deformation, silver writing, poor mold release, clouds, rough punching , Horseshoe shape, small center hole, large center hole, too thick substrate, too thin substrate, large birefringence, low birefringence, substrate rupture, runner fracture, radial stripes, record grooves, halo, pitting , Body burnt, cold material, jet pattern, silver pattern, uneven embossing, slip mark, flash, whisker pattern, surface peeling, bubble, discoloration, cavity, ripple, mold scale, wire drawing, crack, gate cutting Poor, poor measurement, unstable injection volume, main flow channel sticking, salivation, flow line, mold temperature, punching knife, flow channel temperature, injection speed, injection pressure, holding pressure, holding time, switching point, clamping force , Cooling time, barrel temperature, plasticizing time, plasticizing speed, back pressure and other product defects and their causes.

Solutions to defects of plastic injection products:

1. When the screw speed is constant, increasing the back pressure can increase the melt temperature and the shearing effect in the barrel.

2. Modify the mold, especially the pouring system. If the gate is too wide, the turbulence effect is poor when the melt passes, and the temperature rise is not high, so it is not uniform. The ribbon mold cavity should be narrowed.

3. Increase the temperature of the feeding section, especially the temperature at the back end of the feeding section, to make the temperature close to or slightly higher than the temperature of the melting section, so that the masterbatch will melt as soon as possible when entering the melting section, promote uniform mixing with dilution, and increase the chance of liquid mixing.