I’m following the instruction manual

From Harry T…Injection molder in Houston, TX

Question:

 

I’m following the instruction manual, and everything seems to be working correctly but my PC is not drying completely. I’m using a compressed air dryer and I was told that it would dry most materials under most conditions.

 

Answer:


We’ve heard this story before. Unfortunately, you never know when the problem will crop up. Compressed air dryers only produce a dew point of about -10 degrees, under the best of circumstances, but summer temperatures or high humidity can push the dew point up to +10 or +20 degrees. That’s when you notice defects in your molded products.
There are also other problems with regular compressed air dryers but let’s concentrate on your current problem.
First, I think you should call the manufacturer of your dryer and see if there is any way to return it, depending on how old it is and what your warranty says. If that is not possible, ask if they have a membrane option. If you buy the membrane option and install it, you will get -40˚dew point process air and that should solve the current problem.
Note that regular compressed air dryers consume a lot of compressed air and when you add an optional membrane, the compressed air usage goes even higher. Next time you buy a dryer, consider one with a built-in membrane to save lots of energy and be guaranteed that you can dry all resins, regardless of the time of year.

 

Mark Haynie...Sales Manager – Dryer Products, Novatec, Inc.