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New Year’s resolutions for extruders

New Year’s resolutions for extruders
This is the traditional time of year for us to look at the past, present and future . . . by learning from the past, thinking in the present and planning for the future. We call them resolutions, and they are often promises to do something we haven’t done well or at all in the past.

  • Maintenance. See that enough money is budgeted to cover this function (not just spare time for others). Do you have a preventive maintenance schedule that includes what to test, how often, who gets the results and who is responsible for fixing things?
  • Materials. This is where the money is, so people should understand them—things like the difference between regular and linear-low polyethylene; the reason we need to dry nylons and acrylics (they are not the same reasons); why certain additives are used; and what “degraded polymer” means. Also, think about the relation between resin prices and oil prices (around 300 pounds petroleum/42-gallon barrel). You can start with my cartoons from a recent PlasticsToday webinar (e-mail me for a free copy of the Powerpoint slides).
  • Process data. Know the vital signs (melt temperature, melt pressure, motor current), make sure their measurement is reliable and get this information in digestible form to the right people. Know how much is too much for each of these, and find out how excesses are signaled (if they are), where the data are kept and how to get at them.
  • Get reliable measurements of the screw channels and barrel diameter, so you can follow wear and its effect (not always bad). Following output per rpm and melt temperature is more important, and is needed to justify repair or replacement.
  • Be aware of particle size and shape, as they influence intake in single-screw flood-fed machines (most of them). Include bulk density and lubricity in tests on incoming raw materials.
  • Deal with one of my favorite proverbs (see above): “Always put off until tomorrow what you can get away with putting off until tomorrow,” which I have on my wall next to the other proverb, “If not now, when?”
  • Go to industry events like SPE ANTEC in Detroit on March 18 to 21 and extrusion-focussed Minitec in Charlotte on May 1 and 2. If you can’t go, get the list of speakers, call or write the ones that relate to your work and ask them for a copy of what they will say, or at least some comments on it. If you do this after the events, you can read the published papers or at least abstracts, and ask questions about them.
  • Ask yourself what you believe about plastics related to the environment and health. Do you believe that plastics are necessary evils, toxic or otherwise pollutants? If so, where do you get the evidence—is it quantified or just a general image? Do you squirm, as I do, when you see phrases such as “plastic pollution,” “epidemic” or “drowning in plastic?” Do you want your products to look “green” to maintain or gain sales, because of real environmental/health advantages or both? There’s usually nothing wrong with giving customers what they want, but that’s not the same as agreeing with their reasons.
  • And resolve to open and read PlasticsToday e-newsletters as soon as they show up in your in-box. We’ll do our best to get practical and meaningful information to you, but it won’t matter until you read it.

Post your list of resolutions somewhere where you can see it, or put a note in your electronic calendar to check it on the first of each month, or whatever else you can think of that gets you to review what’s been done, what needs doing and what isn’t important any more.

Allan Griff is a veteran extrusion engineer, starting out in tech service for a major resin supplier, and working on his own now for many years as a consultant, expert witness in law cases and especially as an educator via webinars and seminars, both public and in-house. He wrote the first practical extrusion book back in the 1960s as well as the Plastics Extrusion Operating Manual, updated almost every year, and available in Spanish and French as well as English. Find out more on his website,, or e-mail him at

Griff conducts live seminars across the country. The next ones are scheduled for Costa Mesa, CA, on Feb. 20 and Baltimore on March 14. Seminars in your plant are also available. If you can’t attend his live events, he offers a Virtual Seminar, which can be seen at anytime, anywhere. E-mail Griff at the address listed above for more information.

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