A rotomolder of soft plastic automotive dashboards and a blowmolder of plastic bottles, both with special needs, found exactly what they needed at Paratherm Corp. And, in addition to the proper heat transfer fluid for the job, each received engineering assistance in designing and preparing the applications from planning through startup, and ongoing service as the operations are maintained.
Cycling from Forming to Ambient Temps
The rotomolder needed the capability to cycle the process from forming temperature down to ambient in a controlled fashion, to maintain finished-product quality. Such a massive feat of slush molding might customarily take place in an oven chamber, heated by gas or electricity, and cooled by rapid removal of the entire rotational apparatus from the chamber combined with some sort of forced-air blasting.
Instead, an innovative new process was engineered to use indirect heat to accomplish this very demanding feat of temperature-driven quick forming and controlled curing. A single thermal fluid, capable of both heating and cooling, is circulated to the mold through high-performance universal joints while the whole apparatus spins in two axes. Paratherm MR® Mid-Range Heat Transfer Fluid, rated for service from 30-550°F, was selected for this application.
Adding a Food-Grade Requirement
The other processor needed a fluid with similar capabilities. This blowmolder of plastic bottles needed to offer its customers the highest level of confidence in the safety and nontoxic integrity of the end product, containers offered for beverage and food ingredient service. Technically, the operator needed a fluid with the capability to heat and maintain the molds to an application temperature around 300°F in some short runs, and, in other short runs with resins having lower meltpoints, to much lower temperatures that could normally be handled with water-capable equipment. This processor required a single fluid, and a single setup, for both situations.
While not common, fluids with such capabilities are readily available. But this processor also needed the fluid to be registered as food-grade with the appropriate agencies -- to give food ingredient and beverage packagers the extra assurance that all process components and auxiliaries that might contact the polyethylene end product, even if inadvertently, would be as benign as possible. Paratherm MG™ Food grade (NSF Certified) Heat Transfer Fluid, for single-fluid heating and cooling from 30-500°F, proved to be the right solution for the job.
Paratherm''s Sludgebusters™ team provides advice, expertise, and analysis for thermal fluid systems and heat transfer fluids and delivers smoothly operating systems and applications -- and maximum production -- to processors.