Prem Engineering

Shoe Press

 

Shoe Press in the Paper Machine (PM) Press Part

The shoe press is an essential component in the PM press part, classified under presses with an extended pressing zone. It is designed to handle loads ranging from 0 kN/m to a maximum of 1,200 kN/m, providing superior dewatering efficiency and enhancing the overall paper production process.

Design Features

Press Roll:

  • Features bending compensation through a hydraulic system or a classic press roll with crowning.
  • Equipped with a stationary beam to which a set of hydraulic cylinders is attached.
  • The hydraulic cylinders press the “shoe” against the rotating flexible blanket.

Shoe Profile:

  • Influenced by the shape of the loading roll.
  • A rotating elastic blanket on the lower roll slides over a thin oil layer.
  • The hydraulic system allows for precise control of the paper’s cross profile.

Main Parts

  1. Bearing Structure (1):

    • Supports the entire press assembly.
  2. Press Roll (2):

    • Provides the necessary pressure and support for the shoe press operation.
  3. Shoe Press Roll (3):

    • Equipped with a flexible blanket and hydraulic loading system.
  4. Hydraulic System for the Top Press Roll:

    • Controls the load and bending compensation.
  5. Hydraulic System for the Bottom Press Roll:

    • Ensures optimal pressure application and profile control.
  6. Safety Guards:

    • Provides safety for operators and protects the press components.

Accessories

  • Drive System:

    • Powers the press rolls and blanket rotation.
  • Control System and Control Panel:

    • Manages the press operation and hydraulic systems.
  • Assembly Tools:

    • Tools for regular maintenance and elastic blanket exchange.
  • Central Lubrication and Hydraulic Aggregate:

    • Ensures proper lubrication and hydraulic pressure maintenance.

Advantages

  1. Increased Dryness:

    • Achieves dryness levels of 35 – 40% when the entrance dryness is about 48 – 52%.
  2. Energy Efficiency:

    • Reduces steam consumption per produced tonne, lowering energy costs.
  3. Enhanced Machine Performance:

    • Increases the machine’s performance, especially beneficial for machines with limited drying capacity.
  4. Shorter Drying Part:

    • Enables the design of new machines with a shorter drying part, saving space and costs.
  5. Improved Paper Quality:

    • Enhances paper wet strength and overall quality.
  6. Reduced Web Breaks:

    • Minimizes the number of web breaks, improving runnability and effectiveness.
  7. Improved Web Strength Parameters:

    • Boosts parameters such as CMT (Concora Medium Test), SCT (Short Span Compression Test), and Burst strength.

Conclusion

The shoe press in the PM press part is a critical component for modern paper production, offering significant improvements in dewatering efficiency, paper quality, and machine performance. Its advanced design and hydraulic control systems ensure optimal operation, making it an indispensable part of high-speed paper machines.