How To Form The Wet Paper Sheet on Paper Machine

How Did The Wet Paper Sheet Forming on The Fourdrinier Paper Machine

The paper pulp dispersed evenly in the headbox flows at a certain speed onto the forming fabric of wire table. Due to the pressure difference between the two sides of the forming fabric and the vibration of the wire table caused by gravity and suction, most of the water in the paper material is filtered and discharged by the forming fabric. The fibers and fillers in the paper pulp are interwoven and evenly distributed on the forming fabric, forming wet paper sheets.

The Affects of Fourdrinier Paper Machine Forming and Dehydration

1. The properties of pulp include fiber water filtration and pulp ratio, pulp temperature, approach flow concentration, and chemical additives.

2. Dewatering Element: There are many types of dewatering element used in the forming section, and due to their different structural types or specifications, their effects on the forming and dehydration of paper sheets are also different. The commonly used dehydration components are as follows: table roll, vacuum suction box, vacuum couch roll,  water baffle.

3. Forming Fabric: The type and size of the forming fabric have a significant impact on the formation and dehydration of paper sheets. Generally speaking, high mesh number single woven fabric dehydrate slowly, but have a higher retention rate for small fibers and fillers, which is beneficial for reducing the double-sided nature of the paper. For example, when using high viscosity pulp to make thin paper, it is advisable to use high mesh (90 mesh) single woven fabric; Produce general cardboard. Can use 40 mesh single woven fabric; Production of general cultural paper and industrial paper, using a single woven fabric of 60-70 mesh.

4. Paper Making Conditions: The operator needs to rely on various methods to achieve a reasonable dehydration rate and good forming of the paper pulp. Firstly, choose a reasonable spray angle, and secondly, control the ratio of wire table speed to wire speed reasonably; The third is to reasonably control the vacuum degree of the vacuum dehydration component.

5. Vibration of wire table: The vibration of the wire table directly affects the water filtration performance of the paper pulp, and the greater the vibration, the faster the water filtration. If the vibration is too high, it will cause the fibers already deposited on the web to detach from the web surface, thereby damaging the uniformity of the paper. Therefore, it is necessary to strictly control the amplitude and vibration frequency of the web, and choose appropriate ones to improve the uniformity and dewatering performance of the paper.

6. Dandy roll: Its function is to improve the surface condition and surface bonding strength of the top surface of the paper sheet (the side that is not in contact with the wire), and to improve the uniformity of the paper sheet.

7. Defoaming device: steam defoaming device is usually used on the web to reduce foam spots on the paper surface and improve the uniformity of the paper.