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MOLDING TECHNICAL SHEET

WPP > SERIES

Description : 10% Thru 40% Wollastonite Filled Polypropylene

Material Pre-dry : Normally it is not necessary to pre-dry this material. However, dark colors or humid conditions may require drying to optimize material properties and part appearance. Dry material in a desiccant dryer at 180 F for 2-3 hours or 160 F for > 4 hours. Barrel Temperatures (Range): Rear: 400 - 415 F Middle: 410 - 425 F Front: 415 - 435 F Nozzle: 420 - 440 FManifolds: Maintain manifolds, runners and tips 10 to 20 F above the front zone temperature to allow easier filling. (Gate drool is best eliminated using screw decompression rather than reducing tip temperature.) Mold Temperature (Range): 100 - 120 F (Core) Cooler temperatures may be needed 110 - 130 F (Cavity) to maintain dimensions or eliminate sinks in thick sections. Back Pressure (Range): 20 - 50 psi Injection Speed : medium to fast Screw Speed: medium Injection Pressure: Adjust to just above a short shot. Injection Time: Adjust to just above a short shot- Weigh parts for consistent packing pressure and part consistency. Cushion (Range): 0.2 - 0.5 in. Nozzle Type: Free flowing / Standard * Some conditions may have to be altered to obtain acceptable parts. (proper mold filling, dimensional stability, etc.) Please do not run too cold, molded in stress & rough surface may become a problem. If you must run below melt or temperatures recommended for dimensional precision you may compromise impact and esthetics. Retest parts to confirm performance. wppmold 6/99