Weld Line defect analysis and troubleshooting
What is weld line? Weld line, the most common of many defects in injection moulding products. Except for a few very simple injection molded parts, they occur on most injection molded parts (typically in the form of a line or V-groove), especially large complex items that require use of multi-gate molds and inserts. Weld line not only affects appearance quality of plastic parts, but also affects mechanical properties of plastic parts to varying degrees, such as impact strength, tensile strength, elongation at break, etc. In addition, welding marks also have a serious impact on the design of product and life of plastic parts, and therefore it should be avoided or improved as much as possible. Main reason for weld line is that molten plastic encounters in the cavity when insert, hole, flow rate is inconsistent, or area where filling flow is interrupted, confluence of multiple melts occurs; when gate injection is filled, materials...