OMS dryer covers

FEP dryer covers installed on the machine

Short answer: An OMS (On Machine Seaming) dryer cover is a 0.020" FEP fluoropolymer sheet that Fluoron seams around your dryer cylinder while it stays in the machine. The dryer’s steam heat shrinks it on. Clay, starch and coating stop sticking, so you can stop doctoring. Install takes 8 to 12 hours, and covers typically last 12 to 24 months.

Download the OMS sheet (PDF)

Finished FEP dryer cover on a paper machine dryer cylinder
A finished OMS cover on a dryer cylinder at a paperboard mill.

Why mills cover dryers

The first and second dryers after a size press or coater take the worst of it. Starch, clay and coating pick off the sheet and build up on the can. That means picking, sheet defects, doctoring and cleanup. An FEP cover gives the sheet nothing to stick to.

  • Better sheet quality, with no picking or buildup
  • No doctoring needed on covered dryers
  • Less unwanted draw, because the sheet releases instead of following the dryer
  • Often lets you raise dryer temperature and machine speed
  • Stops corrosion on the dryer face
  • Resurfaces pitted and grooved dryers

How OMS installation works

  1. We pull the old cover, if there is one, and clean and prep the dryer face.
  2. We lay chemically etched FEP sheet over the dryer with adhesive.
  3. Our technicians seam the sheets on the machine.
  4. The mill brings up steam, and the dryer’s own heat shrinks the cover tight.
Dryer cylinder with the old cover removed
Step 1: old cover off, dryer prepped.
Fluoron technician seaming an FEP sheet on a dryer cylinder
Step 3: seaming on the machine.
FEP sheet laid over a dryer cylinder before shrinking
FEP sheet in place before shrinking.
Glossy finished FEP dryer cover
Shrunk tight and ready to run.

All OMS installs are done on site by Fluoron service technicians. A recent dryer cover replacement at a paperboard mill in Louisiana took two days, including removing the old cover and cleaning the dryer.

Specs

MaterialTEFLON® FEP sheet, chemically etched for bonding
Thickness0.020" (0.5 mm) standard; thinner or thicker up to 0.125" for special cases
Shrink20% to 30%, using heat from the dryer
Temperature range−400°F to 401°F (−240°C to 205°C)
Install time8 to 12 hours after cleaning and prep
Typical life12 to 24 months, up to 36
FitsNon-felted, non-doctored, internally heated dryer cylinders
CleaningWarm water, soap, industrial cleaners, alcohol, diluted acid cleaners. No scrapers or metal tools.

Not a fit for your dryer?

If the dryer runs a felt or a closed doctor blade, a sleeve isn’t the answer. Our sister company AEGIS Advanced applies X550 field-cured PTFE dryer coatings and harder XR release coatings for those positions. For the rope grooves on the same dryers, see Copley Rope Savers.

Common questions

Does the dryer have to come out of the machine?

No. OMS stands for On Machine Seaming. We seam the FEP cover around the dryer where it sits, and the dryer’s own steam heat shrinks it tight.

How long does installation take?

Once the dryer is cleaned and prepped, the cover goes on in 8 to 12 hours. We plan it around your shutdown.

How long does an OMS cover last?

Typically 12 to 24 months, and some positions run 36 months. It depends on the grade and the position.

Which dryers can take an OMS cover?

Non-felted, non-doctored dryer cylinders that are heated from the inside. A felt wears the cover quickly, and a doctor blade in the closed position scrapes it off.

Will an FEP cover slow down drying?

No. The cover is only 0.020" (0.5 mm), so heat transfer isn’t a problem. Many mills turn dryer temperature up afterward, because picking is no longer a concern.

Can it fix a pitted or grooved dryer?

Yes. The adhesive fills grooves and pits, and the cover leaves a glass-smooth finish that stops further corrosion.

How strong is the seam?

Our seams are virtually undetectable, and the seal is as strong as the film itself.

Planning a shutdown?

Tell us which dryers are picking or building up. We’ll confirm they’re a fit and schedule the install around your outage.

TEFLON® is a registered trademark of The Chemours Company FC, LLC, used under license by Fluoron.

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