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31 Flow Lines
31.1 Description
Flow lines consititute a wide-ranging defect that can appear under a variety of
conditions. The typical flow line will appear as a line or loop on the part surface.
Also in this chapter on flow lines, the concerns of cold flow and hesitation will be
addressed.
Also known as: record grooves, chicken scratches, recording, stalling, hesitation
Mistaken identities: scratches, splay, meld lines, weld lines
31.2 Flow Lines Troubleshooting Chart
Table 31.1 shows the flow lines troubleshooting chart.
Table 31.1 Flow Lines Troubleshooting Chart
Molding Process Mold Machine Material
slow/fast fill velocity wall stock velocity to pressure moisture content
transfer
low fill only weight flow pattern machine performance viscosity
melt temperature filler content
mold temperature 
