Universal Purging Compound Functions Through Broad Temperature Range
MD Plastics' Barrel Blitz Universal purging compound boasts complete removal of carbonized material.
A new universal purging compound that reportedly completely removes carbonized material from the screw, barrel and nozzle of the injection molding machine is being launched in North America at NPE2018 by machinery supplier MD Plastics, Columbiana, Ohio. Manufactured by the U.K.’s Aquapurge, Barrel Blitz Universal (BBU) is made from a stable, easy-clearing polymer and Aquapurge’s proprietary Scrubber Concentrate.
This mechanical purging compound is effective from 320 F to 698 F, so it’s effective for higher temperature materials; is said to be easily cleaned out by any material, including clear ones; is ideal as a strip down material; and is supplied as an easy-to-use free-flowing powder. BBU boasts fast, smooth color changes by removing all trace of the previous job from the barrel. According to MD Plastics, one molder switched from a black part to a white part within six shots by feeding just 6 kg (13.23 lb) of BBU through the hopper.
In addition, difficult material changes such as running PE before PC, which can lead to milky moldings, are reportedly solved when using BBU, as this purging compound is said to ensure that all traces of the PE run are completely removed from the screw and barrel. Recent formulation changes have simplified the process for removing a high-temperature material like nylon before molding a lower temperature material such as a TPE.
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