Hot Runner Melt Channel Design Reduces Color Change Time

For those struggling with color changes, YUDO recommends switching to its hot runner series designed and manufactured for this purpose. YUDO Pack hot runners with ISO manifold technology offer a melt channel design that eliminate hang-up spots, reduce pressure drop and lower shear rate. In turn, this provides process technicians with a wider process window as well as a reduction in color change time.

A European cap producer approached YUDO with the challenge of reducing its color change time. The customer has a total of eight colors that it runs for a particular cap. The time to change between dark to light color was more than four hours. YUDO’s challenge was to reduce this to two hours for each color change.

YUDO’s solution was to use YUDO Pack series hot tips with nozzle tip insulators and ISO manifold technology, which ensures every corner in the manifold has a large consistent radius for good flow through the seamless, uninterrupted melt channel. YUDO designed the manifold heater layout to reduce temperature variation to below 5% in all areas.

The company says it took only two hours and 20 minutes to complete all five color changes. Looking at pure time for color change, not including barrel purging time, it took less than 10 minutes for each test. Overall scrap produced for the entire color change test with the YUDO hot runner was only 75 kg. The customer claimed that they previously scrapped, on average, 300 kg for one color change with the conventional hot runner.