What is the function of the Paper Machine Vacuum Couch Roll
2026-01-05
The vacuum couch is a crucial equipment in the wet-end forming section of a paper machine. It is installed at the end of the Fourdrinier wire and serves as the core component connecting the forming wire and the press section. Its functions are primarily embodied in four dimensions: dewatering, guiding the wire, paper stripping, and forming optimization. It directly determines the dryness, strength, and forming quality of the wet paper web:
1.Efficient dewatering to enhance the dryness of wet paper web
The vacuum couch is equipped with a vacuum chamber inside, creating a negative pressure environment through a vacuum pump. When the forming wire carries the wet paper web across the surface of the couch, the free water in the wet paper web is quickly extracted under the action of vacuum suction and discharged through the drainage system inside the couch. This process can increase the dryness of the wet paper web from 18% to 22% at the end of the forming wire to 22% to 28%, significantly reducing the load on the subsequent press section and drying section, and lowering the energy consumption of papermaking.
2.Stabilize the guide net and ensure the operational accuracy of the net section
As the main support and guide rollers for the forming wire, the vacuum couch rollers have a smooth surface and a certain degree of rigidity, which can support the high-speed operation of the forming wire and prevent issues such as deviation and wrinkling due to uneven tension in the wire section. At the same time, the speed of the couch rollers is synchronized with the paper machine, allowing precise control of the operating speed of the forming wire, ensuring that the wet paper web is evenly stressed during the forming process and improving the thickness consistency of the paper.
3.Strip the wet paper web to achieve smooth transition between work sections
After the wet paper web is formed on the surface of the forming wire, it needs to be peeled off from the wire surface and transported to the press section. The negative pressure adsorption effect of the vacuum couch can firmly adhere the wet paper web to the roller surface. After rotating through a certain angle, the wet paper web can be smoothly peeled off using a scraper or a guide roller, avoiding tearing or breaking of the wet paper web due to insufficient strength, and ensuring continuous and stable production of the paper machine.
4.Optimize paper formation, improve uniformity and strength
Under the influence of vacuum suction, the fibers in the wet paper web will be further compacted and arranged, reducing the inter-fiber pores and enhancing the tightness and uniformity of the paper. Simultaneously, uniform vacuum adsorption can prevent the fibers from flocculating due to rapid local dewatering of the wet paper web, thereby reducing formation defects such as "clouding" and "pinholes" in the paper, and ensuring the physical properties of the finished paper remain stable.
1.Efficient dewatering to enhance the dryness of wet paper web
The vacuum couch is equipped with a vacuum chamber inside, creating a negative pressure environment through a vacuum pump. When the forming wire carries the wet paper web across the surface of the couch, the free water in the wet paper web is quickly extracted under the action of vacuum suction and discharged through the drainage system inside the couch. This process can increase the dryness of the wet paper web from 18% to 22% at the end of the forming wire to 22% to 28%, significantly reducing the load on the subsequent press section and drying section, and lowering the energy consumption of papermaking.
2.Stabilize the guide net and ensure the operational accuracy of the net section
As the main support and guide rollers for the forming wire, the vacuum couch rollers have a smooth surface and a certain degree of rigidity, which can support the high-speed operation of the forming wire and prevent issues such as deviation and wrinkling due to uneven tension in the wire section. At the same time, the speed of the couch rollers is synchronized with the paper machine, allowing precise control of the operating speed of the forming wire, ensuring that the wet paper web is evenly stressed during the forming process and improving the thickness consistency of the paper.
3.Strip the wet paper web to achieve smooth transition between work sections
After the wet paper web is formed on the surface of the forming wire, it needs to be peeled off from the wire surface and transported to the press section. The negative pressure adsorption effect of the vacuum couch can firmly adhere the wet paper web to the roller surface. After rotating through a certain angle, the wet paper web can be smoothly peeled off using a scraper or a guide roller, avoiding tearing or breaking of the wet paper web due to insufficient strength, and ensuring continuous and stable production of the paper machine.
4.Optimize paper formation, improve uniformity and strength
Under the influence of vacuum suction, the fibers in the wet paper web will be further compacted and arranged, reducing the inter-fiber pores and enhancing the tightness and uniformity of the paper. Simultaneously, uniform vacuum adsorption can prevent the fibers from flocculating due to rapid local dewatering of the wet paper web, thereby reducing formation defects such as "clouding" and "pinholes" in the paper, and ensuring the physical properties of the finished paper remain stable.
