Rewet problems

1. Rewetting after the press nip is a result of allowing the sheet to stay in contact with the felt after the maximum transfer of water from the sheet to the felt.
— may require changing the felt run geometry to minimize after-nip contact, especially common on multi-nip center rolls.
2. Rewetting the sheet may be due to a strong sheet/felt attraction.
— check on changing felt design and/or reducing the felt moisture.
3. Rewetting in the press nip is usually caused by water rimming the press roll, incorrect high-pressure roll cleaning showers, or leaking save-all pans.
— check installed rubber wipes for damage allowing localized areas of leakage.
— installation of doctor foil will improve degree and uniformity of roll dewatering.
— leaking save-all pans can be corrected by redesign or operator attentiveness.
4. For nip rewet, check high-pressure showers for grooved or blind drilled rolls to insure correct shower angle and sufficient pressure.
5. Sheet rewet always has a negative impact on press section performance and sheet dryness.