Flow mark

Flow marks, also known as flow lines, are molding defects that can occur in the manufacturing process of injection molding. They are best described as "off tone" wavy lines/streaks or patterns in the molded part around the injection ports. They commonly occur when there is a large variation between cooling speeds of sections of the material as it flows through the mold.^[1]

^ Mathieu, L.; Stockmann, L.; Haudin, J. M.; Monasse, B.; Vincent, M.; Barthez, J.-M.; Charmeau, J.-Y.; Durand, V.; Gazonnet, J.-R (December 2001). "Flow Marks in Injection Molding of PP". International Polymer Processing. 16 (4): 404–411. doi:10.3139/217.1661. ISSN 0930-777X.

[:0-1] Mathieu, L.; Stockmann, L.; Haudin, J. M.; Monasse, B.; Vincent, M.; Barthez, J.-M.; Charmeau, J.-Y.; Durand, V.; Gazonnet, J.-R (December 2001). "Flow Marks in Injection Molding of PP". International Polymer Processing. 16 (4): 404–411. doi:10.3139/217.1661. ISSN 0930-777X.

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