DESIGN GUIDE FOR THERMOSET PLASTIC PARTS （为热固性塑料零件设计指南）.pdfVIP

AKRON PORCELAIN PLASTICS CO. 2739 Cory Ave. P.O. Box 15157 Akron, OH 44314-0157 Phone (330)745-2159 Fax (330)745-6688 Website: email: sales@ Plastics Division ISO 9001:2008 DESIGN GUIDE FOR THERMOSET PLASTIC PARTS General Input on the best molding method for the design concept should be sought early in the design process so the part shape can be optimized accordingly. This will ultimately reduce material and manufacturing costs. Akron Porcelain Plastics can offer significant material and processing information to assist the product designer. As with other plastic materials, good thermoset plastic part design requires consideration of a number of aspects: tolerances, shrinkage, wall thickness, draft angles, radii, fillets, ribs, bosses, holes, threads, inserts, etc. The following suggestions are fundamental practices to follow when designing a thermoset molded part. Tolerances It is best to always design with generous tolerances in mind since extreme dimensional accuracy can be difficult and expensive. The main contributors to dimensional variation in the molding process are: mold dimensions, molding shrinkage, post-shrinkage, warpage, and machine process variations. Typical molding tolerances for properly designed parts are plus or minus 0.003 per inch, and are increased by an additional plus or minus 0.005 when measuring across the mold parting line. Material Shrinkage Each molded part has a characteristic shrinkage defined as the difference between the dimensions of the mold and the molded part when measured at room temperature. Shrinkage varies, ranging from 0.001 t