Blythewood, SC Frank Maples quenches the beverage industry's thirst for PET containers by helping his company, Schmalbach-Lubeca, produce 10,000 bottles per hour. The bottles are typically processed through a blow molder with fluid temperatures that reach 280F in a hot-set procedure used for forming the bottles. However, when a customer that produced isotonic beverages required a cold-set container, Maples knew that would require a change in oil used in cooling the blow-molding machine.
"The problem was the viscosity of the oil," says Maples, the technician who maintains the blow molding machines. "We needed to get the fluid temperature down to about 55F, but at that temperature, the pumps cavitate, and work harder to pump the highly viscous oil, drawing more amperage."
Maples could have used water-glycol, but that would have meant buying new equipment. Use of chloroflourocarbons, which run at cool temperatures, is regulated by U.S. EPA guidelines. Instead, he choose Paratherm MR, a new heat transfer fluid from Paratherm Corp. (Conshohocken, PA).
Paratherm MR is a mid-range heat-transfer fluid rated for service from 30 to 550F. The low-viscosity fluid is nontoxic and contains no chlorinated hydrocarbons, aromatics, heavy metals, sulfur, or nitrogen compounds that are EPA regulated. Its low vapor pressure permits designers latitude in the choice of equipment which does not require pressurization for preventing fluid boiling and pump cavitation.
The fluid's low viscosity requires less pumping energy, so smaller motors and pumps can be specified on batch reactors and molding machines.