CF ChatterFix
Preventive Maintenance

Material Dryer Dew Point Verification

Hygroscopic resins absorb moisture from the air, and moisture in the melt flashes to steam during injection. The result is splay, bubbles, and — with engineering resins like nylon or PET — permanent loss of mechanical properties that no downstream inspection catches.

Interval Monthly
Est. Duration 1.0 hr
Steps 4
Applies To Plastics & Injection Molding

The Procedure

The steps ChatterFix schedules for this PM. Every step is a checkable item on the work order — a technician can speak their way through it without touching a keyboard.

  1. Measure and record dew point at the hopper inlet
  2. Inspect and replace return and process air filters
  3. Verify process temperature against the resin spec
  4. Check hoses for leaks and desiccant for contamination

Why This PM Exists

Hygroscopic resins absorb moisture from the air, and moisture in the melt flashes to steam during injection. The result is splay, bubbles, and — with engineering resins like nylon or PET — permanent loss of mechanical properties that no downstream inspection catches.

What Skipping It Looks Like

Splay that gets chased with process changes for days, and structurally weak parts that pass visual inspection and fail in service. This is the defect most often blamed on the resin supplier.

Setting the interval

Verify dew point monthly at the hopper inlet, not at the dryer outlet. Filters and desiccant condition drive most failures — check both.

Equipment This Covers

Common Questions

How often should this PM run?
Monthly. Verify dew point monthly at the hopper inlet, not at the dryer outlet. Filters and desiccant condition drive most failures — check both.
How long does it take?
Budget about 1.0 hour for a technician working to the standard procedure. ChatterFix uses that estimate for capacity planning, then learns your plant's actual time from completed work orders.
What happens if we skip it?
Splay that gets chased with process changes for days, and structurally weak parts that pass visual inspection and fail in service. This is the defect most often blamed on the resin supplier.
Can I use this checklist in ChatterFix?
Yes — this exact procedure ships in the Plastics & Injection Molding industry pack. Pick your industry at signup and it is scheduled on the right assets automatically, with no configuration.

Related Procedures

Stop Retyping Your PM Library

This procedure — and every other PM for your industry — is already built into ChatterFix. Pick your industry and it lands on the right equipment, on the right interval, in about three minutes.