How to Improve Press Felt Dewatering in Paper Machine Press Section?

The Importance of Press Felt Dewatering Efficiency

The water absorption and filtration properties of press felt have a significant impact on the dehydration effect. The material, weaving method, and specifications of the press felt will directly affect the dehydration effect. In addition, as the usage time prolongs, the felt will gradually wear out, become thinner, increase in density, and narrow the press zone, which will actually enhance its dehydration ability. However, at the same time, the felt will gradually become dirty, leading to a decrease in dewatering capacity, which will have a negative impact on the continuous production of the paper machine. Therefore, maintaining the cleanliness of the felt is crucial to ensure smooth production.

Methods for Increase The Press Section and Press Felt Dehydration Capacity

• Increase The Pressure Line on The Press Zone

For paper machine method: increase the hardness of the press roll; Increase the number of press rolls; Increase the line pressure of each press roll; Increase the diameter of the press roll.

For press felt method: Reasonably choose the structural proportion and organizational structure of the felt to improve its pressure resistance performance.

• Increase Dehydration Time and Press Zone Area

For paper machine method: Adjust the eccentricity of the press roll and the angle of the felt pressing; Adopting a new type of large roll diameter and wide compression zone press method; Adopting double felt press form.

For press felt method: Improve the elasticity recovery performance and water holding space of the press felt.

• Increase The Fluid Pressure Difference in The Pressure Zone

For paper machine method: Use vertical dewatering press form; use dry press mothed; increase the cleaning of press felt.

For press felt method: Increase the press felt filtering capacity and self cleaning capacity.

• Increase The Pressure Uniform of Press Zone

For paper machine method: choose suitable material for press roll; choose suitable crown of press felt; choose reasonable surface opening rate of press roll.

For press felt method: Increase the uniform of press felt bottom layer and batt layer; increase press felt surface flatness and fineness; adjust suitable structure of base later and the thickness of the weft and warp yarn.

• Reduce Rewetting

Paper machine methods: Adjust the felt angle correctly when the felt is out of press section; make the wet paper sheet separate quickly with the felt after press section.

Press felt methods: Adjust the felt surface features , surface fiber thickness, denisty and forming status.