Look to PlasticsToday's Product Watch for updates on recent developments in the world of plastics processing machinery. New for rotational molders is the Carrossel independent-arm rotational molding machine from Rotoline Industrial Equipment Ltda. (Chapeco, Brazil), an affiliate of Reduction Engineering Inc. (Kent, OH). The company will introduce the machine at the Brasilplast exhibition this month (May 9-13) in São Paulo, Brazil.
The new unit features Rotoline's round-shape oven and "reverse air re-circulation" with a more powerful oven burner system than previous systems, leading to more efficient heat distribution. Straight arm configuration is standard with offset arm an option. Efficiency of these rotomolding machines is improved by balancing the recirculation fan, exhaust fan, and the burner position controlled by a proportional-integral-derivative (PID) program, thus reducing gas consumption and cycle time, according to the company. The company's circular oven has no dead space and so helps with greater fuel efficiency.
The machine's five stations (oven, pre-cooling, cooling, unloading, and loading) permit great versatility in production. With independent arms, the operator can make adjustments at different times on each arm for process optimization. The system has Allen-Bradley controls, and all of its wiring is integral and included with the machine upon startup with "plug and play" connections to the general panel.
ADG Solutions (Fairfield, CT) is now the exclusive North American importer of a patented continuous screen changer developed and manufactured by Italy's Fimic Officine Meccaniche SAS. The screen changer has a 20-year track record outside North America, where users have found it possible to reprocess highly contaminated plastics scrap without the extruder downtime or constant operator intervention that conventional systems require for cleaning away buildup from the filter screen.
ADG has already shipped five of the screen changers and has several on order, according to Sandy Guthrie, president of the company, which he founded recently. Guthrie started his plastics career in 1978 with a sales position at Sterling Extruder, which had been founded by his father. He became director of sales for Sterling and then, in 1989, joined Davis Electric as president of that manufacturer of wire/cable production equipment. In 1991, Guthrie founded Merritt Extruder, which merged with Davis Electric in 1994. When Merritt Davis was sold to Davis-Standard in 2005, Guthrie stayed on as business director until December 2010.
Of his new business, he says, "The mission of ADG Solutions is to provide equipment systems that can transform plastics scrap into high-value raw material, regardless of the original condition of the scrap or the difficulty of handling it." In addition to the Fimic screen changers, ADG also offers reclaim extruders and systems from Davis-Standard and washing equipment from Italy's Tecnofer, The company also offers a range of size reduction systems for polystyrene foam, with those machines manufactured by ADG Solutions. This equipment achieves a 90:1 reduction in volume, densifying PS foam from 0.5 lb. per cubic foot to 45 lb/ft3. The machines size-reduce, melt, and prepare the material in a form that can be ground for reuse.
"The Fimic screen changer can handle scrap containing up to 3% loadings of paper, labels, or cardboard without a slowdown or stoppage of the process, and even contaminants close to an inch in diameter do not pose a problem," said Guthrie. "The self-cleaning action is very efficient, with purgings averaging less than 2.5 lb. per cleaning cycle and minimal discharge of good material along with contaminants."
The self-cleaning cycles are subject to automatic PLC control. In each cycle, as molten polymer enters the screen changer, contaminant accumulates on the screen plate, which is a stainless steel component drilled to the equivalent of a 40-mesh screen. The buildup continues until backpressure reaches a preset level. This actuates a rotating blade that sweeps the screen and purges the contaminant through a central discharge port.
Alternatively, cleaning can be actuated automatically according to a pre-set timer, or manually at the push of a button.
Besides paper, the system can handle other contaminants, such as metal foil, wood, textile fibers, and un-melted plastic. Four models are available, with screen diameters from 12.5 - 25 inches and throughput capabilities from 1200 - 6000 lb/hr. Replacement screens and blades are available. Working life of a screen is typically two weeks.
In other plastics machinery news, Battenfeld Italia s.r.l., a 100% subsidiary of Austria's Wittmann Battenfeld, has been renamed as Wittmann Battenfeld Italia. From July it will supply the company's complete range of injection molding machinery plus the Wittmann auxiliary equipment and robots into the Italian market. The Italian subsidiary is in Solaro, near Milan. The company has long been responsible for the sales and technical service support of the Battenfeld (now Wittmann Battenfeld) injection molding machines and, more recently, the Tempro temperature controllers made by the Wittmann Group.
The final item in this Product Watch segment is White Rhino, which its supplier, Slide Products (Wheeling, IL) says is the only rust preventive to achieve the NSF H-1 designation permitting use in operations requiring food-approved active ingredients. The preventive also contains no trichloroethylene. With the NSF H-1 designation, this rust preventive is good for molding operations requiring food-approved ingredients or for medical molding projects.
According to the supplier, White Rhino offers up to 2 years of protection under normal operating conditions. Its dry formulation neutralizes fingerprint acids and is self-cleaning and self-healing. It sets up quickly to offer protection against moisture and light acids.
Slide's Super Grease lubricant has also acquired the NSF H-1 designation. Slide also has mold releases and mold cleaners with food-approved active ingredients. NSF is a non-profit, non-governmental agency that helps develop industry standards. In recent years it has taken over tasks previously handled by the FDA and now handles the testing and certification for food equipment.