Plastics Technology

MAY 2012

Plastics Technology - Dedicated to improving Plastics Processing.

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Advertisement Q. Can this be integrated with existing drying hoppers even though they aren't Novatec drying hoppers? A. Yes, MoistureMas- ter™ can be retrofit- ted to an existing drying hopper. No matter if the drying hopper is from Conair, AEC, UNA-DYN, Motan or others–the sensor can easily attach to the base of the hopper. Novatec has a host of adaptors and diverter assemblies to help you get it installed quickly and easily–and the retrofit is available today. Q. Can this be integrated in material lines as well? A. Yes, MoistureMaster™ can be installed in material lines as well–for example in a silo line to verify moisture content of incoming resin. Q. What are the limitations today? A. There is no minimum throughput, but the maximum throughput is currently about 3000 lb./hr. based on pellets with a bulk density of 38 lb./ft 3 . Adaptor flanges are available to connect the MoistureMaster™ drying hopper up to a large silo flange. The current MoistureMaster™ to temperature limitations, although we expect to introduce MoistureMaster™ MoistureMaster™ PPM receptivity down to the 5-10 PPM range. Q. What is the sample size? How often does MoistureMaster™ take a measurement? A. The sampling zone has a volume that encompasses about 1 lb. of material. Nearly one million measure- ments are taken every second (something that couldn't be done with earlier control technology). The mean average for this time frame is then recorded. This gives the user a nearly continuous online reading of the moisture of the pellets passing sensor to anything from a small is not for bottle grade PET due PET later in 2012. The PET version will also have targeted through the chamber. With the separate Novatec MoistureMaster™ controller, you can then monitor and trend your pellet moisture online and automati- cally. The controller can also broadcast the trending to your in-house QC system. Offline measurements should be a thing of the past–and your employees can get your process under control. Q. How do we verify that the measurement system is working correctly? How do you calibrate the device? What level of maintenance is required? A. MoistureMaster™ has a built-in self calibrating func- tion that should be sequenced about once a month. It can also be calibrated using a moisture specific offline analyzer or Novatec can check samples on a regular maintenance basis. Since there are no moving parts, there isn't a preventative schedule involved here. Q. What is the lowest level of moisture capable of being measured? A. The sensor can maintain its accuracy of ±10 ppm down to a value of about 50-100 ppm. The upcom- ing MoistureMaster™ PET will be targeted at 5-10 PPM levels for PET bottle production. Q. Does MoistureMaster™ need to be calibrated for each resin type? A. MoistureMaster™ needs to be set for the resin family (ABS, PC, etc.) that is being measured. At present, there is a list of over one-hundred resin families that have been pre-calibrated in the PLC controller which should satisfy the vast majority of applica- tions. If you have a new resin that's not on the menu, Novatec can test it for you and send you the special codes to upgrade your PLC. Q. Can MoistureMaster™ measure the moisture in regrind, flake or granules? A. The shape and particle size doesn't affect the ability to accurately measure the moisture content. The value displayed from the sensor will be the average moisture of the virgin/regrind mix that is currently in the measurement chamber (prox 1 lb.) If the moisture is varying, the output will show what the average value is for all the material in the sensor at that time. If the mixture has been blended, the blend should also reflect a consistent average.

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