← Defect Guide

Flow Mark

Wavy or streaky marks along the flow direction, mainly from low mold temperature or injection speed.

◆ Common Causes

  • •Mold temperature too low (especially early shots)
  • •Injection speed too low
  • •Melt temperature too low
  • •Flow restriction at gate/runner
  • •Insufficient warm-up

◆ Solutions

  • ✓Raise mold temperature (into recommended range)
  • ✓Increase injection speed
  • ✓Raise melt temperature and injection pressure
  • ✓Consider enlarging the gate
  • ✓Warm up before judging early shots

◆ Resin-Specific Notes

PP

Prone to waviness at low mold temperature. Secure mold temp.

ABS

Improves well with mold temperature and speed.

PC

High viscosity. Adequate melt and mold temperature.

◆ Resins Prone to This Defect

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This content is a field-reference summary. Final judgment requires on-site engineer verification.

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