Multi-Nip Press Part – TRI-NIP

The TRI-NIP press part is a compact set of four press rolls forming three nips. It is designed to optimize the press part of the paper machine, particularly with a shoe-press module in the third nip position. This configuration enhances dewatering efficiency and paper quality, especially suitable for high-speed machines.

Design Features

Press Rolls and Nips Configuration:

• 1st and 2nd Nips:

  • Utilizes a three-chamber suction roll as the central roll.
  • Three-Chamber Suction Roll: Contains two high-vacuum chambers for felt water suction at the nip points and one low-vacuum chamber for paper transfer from the 1st to the 2nd nip.

• 2nd and 3rd Nips:

  • A smooth press roll without a felt acts as the central roll.
  • Smooth Press Roll: Dimensioned for two nips with a linear load up to 1200 kN/m, ensuring paper transfer from the 2nd to the 3rd nip.

• 3rd Nip:

  • Features a combination of a shoe-press module and a stationary press roll.
  • Shoe-Press Module: Allows higher linear load pressing in a wider nip, achieving better dewatering.

Advantages

1. Shortened Paper Track:

   • The compact configuration reduces the paper track length in the press part.
   • Eliminates free draw forces, ensuring continuous paper contact with rolls.

2. Improved Dryness:

   • The shoe-press module in the 3rd nip increases dryness after pressing to over 50%.

3. Stability and Efficiency:

   • Ensures paper stability during passage through the press part.
   • Increases machine efficiency and runnability.
   • Optimized for high-speed machines, reaching up to 1000 m/min.

Main Parts

1. Pick-up Suction Roll:

   • One-chamber or two-chamber suction roll for transferring paper from the wire part to the press part.

2. Bottom Press Roll:

   • Ø 980 mm with coating, includes felt for dewatering.

3. Three-Chamber Suction Press Roll:

   • Ø 1,120 mm with coating, includes felt for high-efficiency dewatering.

4. Central Press Roll:

   • Ø 1,250 mm with coating, smooth surface for efficient paper transfer between nips.

5. Bearing Structure:

   • Supports the press rolls, made of common steel.

6. Shoe-Press Module:

   • Positioned in the 3rd nip for enhanced dewatering performance.

7. Felt Guiding, Cleaning, and Dewatering Equipment:

   • Ensures optimal felt performance and maintenance.

Material

• Bearing Structure and Guide Rolls: Made of common steel.
• Press Rolls Embedding: Made of cast iron.

Accessories

• Roll Removal Equipment
• Jumbo Press Drive (Mechanical and Electric Part, Control Included)

Scope of Delivery

• Complete machine as per main parts description.
• Optional accessories as required.

Advantages

1. Elimination of Re-Wetting:

   • Improved dewatering efficiency prevents re-wetting of the paper.

2. Increased Dryness Content:

   • Higher dryness levels after the press part enhance paper quality.

3. Paper Guiding:

   • Ensures paper is guided without free draw forces, improving stability.

4. Shortened Press Part Length:

   • Compact design reduces the overall length of the press part.

5. Maximum Paper Wet Strength:

   • Enhanced strength parameters such as CMT, SCT, Burst, etc.

6. Optimal Configuration:

   • Suitable for high-speed machines.
   • Achieves optimal paper voluminosity (density/thickness ratio).

The TRI-NIP press part offers a highly efficient and compact solution for modern paper machines, ensuring better dewatering, increased dryness, and improved paper quality, all while maintaining high operational speeds and stability.