Technology Takes Aim At Drying Specialized Resins
Novatec develops new at-the-press drying solutions for molders tackling highly tailored nylons and other specialty materials.
An increase among molders in running highly tailored nylons—some for the first time—has encouraged Novatec to develop features aimed at ensuring these materials are dried properly. As a result, Novatec has taken two technologies established in central drying and adapted them to its line of NovaWheel portable dryers: Moisture Manager and OverDry Protection.
Novatec’s Moisture Manager uses valves in the dryer and a dewpoint measurement out of the drying hopper to determine if moisture is being pulled from the resin, or if the resin is already dried to the appropriate moisture level. If the resin is already dry, the blower loop will exclude the desiccant, recirculate and heat without using dry air at -40 F/C dewpoint. If, however, the moisture monitor in the hopper outlet senses that the resin requires additional drying at any point, dry air is introduced into the loop automatically, and then bypassed again automatically when the desired dryness is achieved. Each resin can have a recipe that ensures proper resin moisture always.
As for OverDry Protection, once this feature is turned on, the dryer will automatically adjust the drying setpoint parameters to maintain the correct drying temperature based on an algorithm in the control program. Once the operator inputs the desired drying temperature, the dryer control takes it from there, determining the appropriate hopper exit temperature at which the drying temperature should be reduced, and automaticallyfind the temperature that gives the proper temperature profile in the hopper. No further intervention is necessary, and the dryer will automatically adjust and maintain the temperatures to have a consistent drying-temperature profile.
In cases where operators change a gaylord or resin source—and the resin temperature or moisture is different from the previous lot—the dryer control automatically adjusts to maintain the temperature profile.
OverDry Protection will be standard on Novatec’s NovaWheel portable dryers; Moisture Manager will be available as an option.
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