Long runs and the high output of extrusion molding can result in an elevated scrap rate on extended changeovers with long periods of dead time in between production runs. Luckily Purgex™ delivers versatile purging compounds for extruders designed for performance and engineered to combat these challenges extrusion molders face. With its unique foaming action, Purgex effortlessly flows into tight spaces to remove material build-up while still retaining the power to muscle out contaminates.
Purgex purging compounds:
- Pass through dies as small as .030″ (.755mm) in diameter.
- Have a proven, successful history in purging both single- and twin-screw extruders.
- Clean multiple resins for multi-layer extrusion processes.
- Grades are available for a wide range of resins and melt indexes (MFI).
Color/Carbon Streaking
One of the most common problem areas when purging extrusion molding machines is streaking. This streaking occurs when either color or carbon isn’t completely removed from the extruder or die after purging. The easiest way to diagnose the actual cause of a molder’s streaking problem is to see when the streaking initially occurs. The general rule of thumb for this is:
If the streaking happens right after a purge, that generally signifies that the user’s current purging material, whether that’s resin or a purging compound, isn’t effectively reaching that area and cleaning the two ends of the die head.
If streaking is noticed mid-run, it could be a result of a purge material reaching, but only covering the contaminants. Eventually, material flowing over these covered contaminants during a production run will expose the contaminant to your production resin and produce an unwanted line of color.
Resin or standard purging compounds for extruders can have trouble reaching and cleaning key problem areas that cause streaking such as the far ends of the die head. Purgex purging compounds unique foaming quality and cleaning power allows Purgex to target these areas and completely remove production-delaying contaminants.
For Purgex grades recommended for Extrusion, see our Purgex Products page.