TPT July 2007

P lastic & C omposite T ube

New ‘Yellow Jacket’ vertical extruders for coextrusion

Wayne Machine & Die Company, USA, has launched a new Yellow Jacket vertical extruder series. This series is unlike typical vertical extruders with inline gearboxes that have all the weight of the mechanical section on one side of the post. Instead, the motor is positioned on the opposite side of the extrusion processing section, resulting in a more balanced weight distribution. This helps to prevent ‘tip overs’ – a major safety problem with vertical extruders. The design also allows the use of double reduction helical gearboxes with shaved ground and hardened gears. These are an alternative to the often inefficient soft gear worm or enveloping worm-type gearboxes that are typically found on direct drive vertical extruders. The helical gearbox enables delivery of more power to the screw, less wasted energy converted into heat from friction, The Prandelli Plus system, from Prandelli SpA, Italy, consists of a PE-Xb/AL/PE-Xb composite pipe and dezincification-resistant brass connectors. Connections are made using an axial sliding operation. During the manufacture of Prandelli Plus pipe the inner core is covered lengthwise with butt-welded aluminium foil. The fluid runs through this inner core, with full compliance with PE-X pipe standards. The fi The Prandelli Plus system uses PE-Xb/AL/PE-Xb composite pipe and brass connectors

and less abrasive gear wear than is found in worm drives. Processors are able to run engineering and highly filled resins in coextrusion applications, which require high levels of screw torque. The extruders also process PE, PVC, EVOH, PP, TPR, silicone, rubber, food and most thermoplastics. A high temperature/anticorrosive package is also available for Teflon FEP, Saran, ETFE, PFA and liquid crystal polymers. The new single-post series is available in ½", 5 / 8 ", ¾", 1", 1¼", and 1½" sizes, while the double post machines are designed for 2" and 2.5" sizes. The units feature timing belts for easy speed range changeovers, AC flux vector drive, auto-tune temperature controls, bimetallic barrels and optional remote stations. Suitable for coextrusion of sheet, tubing, profile, rod, blown film, cast film, fibre, aluminium is then covered with a further layer of cross-linked polyethylene (PE-Xb). Due to the size of the pipe, the finished product has high mechanical and thermal resistance, making it suitable for both heating and sanitary systems, the latter often being under stress. Important characteristics of Prandelli Plus pipe include corrosion proofing, smooth and even surface, thermal conductivity, low noise, and a barrier to oxygen. Prandelli Plus has been designed to safely withstand any stress that may occur within hydraulic, heating and sanitary systems. The tube can be classified as PN16, meaning it can withstand a pressure of 16 bar at a temperature of 20°C for a continuous operation period of 50 years. The tube can work constantly at a running temperature of 60-70°C. It can withstand temperatures of up to 80°C and malfunction temperatures of the hot water generator or control systems of up to 95°C. For applications in panel heating systems, the maximum temperature is 90°C and the malfunction temperature is 100°C, as provided for by the specific UNI EN ISO

Pipe for heating and sanitary systems

15875-1 regulations. Prandelli SpA – Italy Fax : +39 0308 921739

Email : prandelli@prandelli.com Website : www.prandelli.com

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J uly /A ugust 2007