In normal blow molding of a part, we encounter stretching and thinning of the parison as it blows in the mold cavity. The technique of die shaping is one of the methods to improve and help balance overall wall thickness for improving thin area of a part and/or lightweighting.
Includes a discussion of the following:
Wall distribution obtained in typical blow molded parts.
Parison programming and die shaping to improve and/or balance wall distribution in a part.
Methodology to incorporate die shaping into the die tooling to improve wall distribution.
Biography
John Rathman is presently Principal Blow Molding Specialist at the Plastics Technical Center of Chevron Phillips Chemical Company LP located in Bartlesville, Oklahoma.
He joined Phillips Petroleum Company in 1976 at the Plastics Technical Center. He has worked in various technical areas of blow molding during his career at Chevron Phillips (milk and water bottles, bleach and detergent bottles, injection blow molding, automotive) and with special emphasize on large part blow molding.
John is an Honored Service Member and Fellow of the Society of Plastics Engineers. He has been an active director for the SPE Blow Molding Division since 2003. Also, he has held various positions on the board of the Bartlesville-Tulsa Section, which is now part of the Oklahoma Section.
