Foam in the coating circuit

Medium severity

Symptoms

Bubbles leaving craters or uncoated voids

Probable causes

  • Air in recirculation
  • badly primed pump
  • exhausted defoamer
  • high viscosity

The Print Guy · 2026-10-05

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All Water-based coating problems (8) →

Other categories

Wire/Spiral binding (7)Binding (hotmelt/PUR) (8)Blankets (7)