WebApr 10, 2024 · Unreasonable hot runner size. Solution. Improve injection speed and melt flow. Improve the exhaust system of the mold. Increase the mold wall thickness and switch to a grade where the melt flows easily. … WebCommon defects linked to the processing of the plastic resin in the mold include: Blistering – Bubbles or raised imperfections that are generally caused by too much heat and/or …
Scary Plastic Part Defects and How to Avoid Them
Flow lines are off-color lines, streaks, and other patterns that appear on the surface of a part. These are caused by the shot of molten plastic moving at different speeds throughout the injection mold, which ultimately causes the resin to solidify at different rates. This is often a sign that injection speed and/or … See more Sink marks appear as depressions, dents, or craters in thick sections of a part. Thicker sections take longer to cool, which can have the often unanticipated side effect of the inner … See more What is delamination? Delamination is a condition that causes a part’s surface to separate into thin layers. These layers, which appear like coatings that can be peeled off, are caused by the presence of contaminants in the … See more “Short shots” refer to instances in which the resin doesn’t entirely fill the mold cavity, resulting in incomplete and unusable parts. What causes short shots in injection molding? Typically, they are the result of … See more Also called knit lines, these defects mark where two flows of molten resin came together as they moved through the mold geometry. This … See more WebDec 1, 2001 · To solve weldline and flow mark defects, the gate thickness is reduced to increase the melt front velocity and the melt front velocity of the flow mark area is … towing service for private property
Flow Mark in Injection Molding: Causes and Solutions - Moldie
WebNov 16, 2024 · Most Common Injection Molding Defects: 1. Burn Marks: One of the most common injection molding defects is “burn marks.” On molded plastic pieces, burn marks are black or rust-colored … WebNov 22, 2024 · 1．Mold Temperature Too Low. If the mold temperature is too low, the material temperature will drop very fast, so the injection pressure and the holding pressure will not be high enough to press the … WebMay 9, 2024 · Reduce the injection pressure. Reduce the temperature of the mold and plastic being injected. Check the diameter of the ejector pins and the pin hole … towing service brooklyn