“Purging Compounds are too expensive. We will use our own resin or regrind instead.”
These are the famous last words of a plant manager who is about to cost his company tens of thousands of dollars.
I hear comments like this more and more from people in the purchasing department at plants I'm visiting. The problem lies in the fact that most of the materials they purchase are used to create products. Purging compounds are sometimes mischaracterized as a miscellaneous cost that doesn't quite fit in their normal accounting. Purging compounds are not just a maintenance item, but rather an instrument to increase profits for the company by reducing down-time in several ways, and increased part-to-part quality or fewer rejects, less resin scrap.
Here are a few ways to reconsider the true cost of regring vs. purge:
-Conduct a cost analysis to determine to true cost of purging. First, calculate what your downtime cost is. For reference, It may be $500 per hour, not including loss of production. Next, log your down-time between changeovers, and weigh the amount of resin or purge that is used and scrapped.
-If In-house regrind is prevalent and not feasible to be reapplied in production, then consider turning to your local scrap dealer. Check with more than one scrap dealer to get fair market value for you clean regrind. Natural and separated colors will be more valuable than mixed color. Say perhaps you get .25/lb. for the regrind, then put that into a budget for a truly cost effective purge product.
-The purge product usage should be significantly less than the resin, but the big savings comes when achieving a reduction of 65% less downtime. Turn that downtime into productivity, and suddenly you're exponentially more profitable on paper.
-Without fail, you will find that the resin or regrind alone is much more costly in the long run. The same is true with cheaper quality purging products. When considering a purge compound, don’t get hung up on just the price as they are not all created equal. Get a free consultation and find out what's best for your process and resins.
Once you have selected your high performance purging compound for cost effective changeovers, it is very important to stick by your plan to be dramatically more efficient. Standardize the procedure to ensure proper use and create a “Table of Quantity” for each machine. In other words, if machine #3 requires 4 pounds of purge, then use only 4 pounds. Using additional product is wasteful and your results will see diminishing returns.
Learn about the importance of implementing proper purging procedures by downloading this free industry guide.