I won’t forget and won’t let you forget, either: There are no toxic plastics, but people want to think so because they are changeable/moldable and “chemical.” The science of chemistry, like all science, challenges belief in the impossible, which we all need to some degree. So we are scared of this “unknown” and don’t really want to know it well, lest we see the nontoxic truth.
Now to maintenance of extrusion lines. Some of you are old enough to remember Bert Lance, Jimmy Carter’s banker friend and budget director, who popularized the expression, “if it ain’t broke, don’t fix it.” The folksy, ungrammatical structure appealed to the anti-intellectual sentiment popular at the time. It may be sound advice in banking and politics, but not in a factory, where staying alive means doing things to avoid both kinds of broke.
We would all agree that you fix things that are broke(n), but even this isn’t so simple. There may be a choice between buying a new one or fixing the old one, which then depends not only on direct cost but also on delivery and installation time and whether it will affect production: Will it slow down production? Stop it? Reduce consistency? Change product properties? And then, whether it’s new or old, you need to consider the maker and features that you want, the payment terms and so forth. It’s like deciding when to buy another car—new or used, cash or loan, maker’s guarantees and expected service life.
Even fixing the old is not so clean. If your car fender gets loose, maybe after backing into something you can’t put the blame on, do you crawl under the car and wire it up until you need to go to the auto shop for something else and have it fixed while the car is on the lift anyway? Or do you get it to the shop ASAP and rent a car in the meantime, whatever it costs, so no one sees the damage? Maintaining an image should not be part of running a factory, but it often is, especially when sales are involved. It may be OK to care about the image, but admit it, and don’t look for technical reasons that don’t exist. That’s like blaming plastics for the reduced fish catch this year or next.
Separate preventive maintenance from responsive maintenance.