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How to Shorten Purge Time & Start Molding More


Purging is a necessary evil for any molders existence. Profits are in the molding, not in the time lost purging. Completely removing the old and unwanted resin from the screw and barrel assembly means greater quality control. Doing it quickly means you are back online faster and molding more.

The main reasons for purging are:

  • color changes
  • resin material changes
  • to eliminate black specking
  • and routine maintenance

And a purge can take 10 minutes or up to 10 hours depending on the severity of the problem.

Choose the right purge

Slide Products offers two efficient purging compound solutions, which can be reviewed in more detail at Slide Products purging page on the web.

Purge Solution #1

Slide PDQ is a water-based purging compound to be mixed and used with a carrier resin. As the mixture is moving down the length of the barrel, the compound will physically “soft scrub” the old and unwanted resin. PDQ scours the screw and barrel to help soften the resin. This scrubbing action will break free the resin and aid with its removal. PDQ is inexpensive and very easy-to-use. If you perform frequent color changes or light-duty purges, PDQ is an excellent option.

Purge Solution #2

For heavier-duty purges that involve a stubborn resin, hard color changes such as black to white, or purges of a machine that has not been cleaned out for a long time, Slide NPT (NuPurge Technology) is your best choice. NPT is a chemically-reactive purging compound that works with the heat of the machine to set off a series of chemical reactions that destabilizes the unwanted resin, effectively altering the viscosity of the resin so that it is much more fluid and more easily pushed out the machine. While NPT is a premium purging compound, NPT performs better for nearly all purging requirements.

An investment that pays you back

Finding the right purging compound is truly an investment in your productivity. The less time required to effectively purge is time spent molding. So though cost of any purging compound is always a consideration, the cost-to-time saved ratio is the ideal way to evaluate which purge is best for you.

Both Slide PDQ and Slide NPT are designed to reduce the amount of time needed to purge, and consequently, a molder’s overall cost to purge. When evaluating a purging compound, it is important to include all costs in the analysis.

These costs should include:

  • the cost of the purging compound
  • the cost of any wasted resin
  • and most importantly, the cost of the machine downtime.

Try before you buy

Using an effective purging compound like those offered by Slide will help to reduce the cumulative costs to purge. Trial samples of the Slide purging compounds are available online at And unlike many other companies offering purging compounds, Slide Products has an extensive network of local distributors available to aid you with your purge test. If you are interested, please email your request to Slide Products.

Start saving money and contact Slide Products today.


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