Ultra Purge Solves Cap Manufacturer Issues

Moulds Plus International was approached by a cap manufacturer that was having issues with black specks showing up in the parts. The molder’s current method for purging was to run resin through the machine for both color changes and carbon removal. The company had been processing blue caps (figure 1) for a week and transitioned into a white cap (figure 2). Black specks (figure 3) had been showing up sporadically in the white caps for two days when the molder contacted Moulds Plus for assistance. An Ultra Purge Representative visited the company with a sample of the Ultra Purge P-O grade. The P-O grade is a 100% moldable purge compound that is recyclable and hot runner safe.

The trial was run on a 150 ton press and with a 16 cavity hot runner tool. In order to purge the hot runners parts were molded out of the Ultra Purge P-O (figure 4). The Ultra Purge P-O pulled out carbon specks and broke old colorant lose from the hot runners which showed up in the part as a brown color (figure 5). Brown color had never been run through the tool before but the combination of all the colors that had been processed resulted in a brown color being removed from the machine. Good parts were being produced ten shots into the white color.

As a result of using the Ultra Purge to clean the hot runners the molder was spared from sending out the tool to have it manually cleaned. The cap manufacturer is in the process of instituting standard procedures for using the Ultra Purge for all dark to light color changes and to purge any machine/hot runner that black specks start to show up on. The consistent use of Ultra Purge will keep the color and carbon from building up in the hot runners.

Remove black specs from caps