How does a paper machine work

A paper machine is a necessary papermaking machine for every paper mill. The emergence of this machine has replaced the traditional manual papermaking, which not only improves the quality of paper but also improves the production efficiency. For special understanding, let the editor of China Paper Industry Network give you a brief introduction:

The paper machine can be divided into fourdrinier wire type, rotary wire type, sandwich wire type, stack wire type and facing roll type if it is divided according to the structure of the wire part. Papermaking machinery can be said to be a linkage machine composed of multiple pieces of equipment. The parts of the machine are divided into two parts: wet part and dry part. Wet end parts include stock flow equipment, wire section and press section; dry end includes dryers, calenders and reels.

After mixing, sizing, filling and purification, the raw materials are converted into pulp with papermaking properties, and then the pulp is sent to the pulp flow equipment of the paper machine at a concentration of 0.3%-1.3%. After the distribution and leveling of the slurry by the slurry flow distributor and the headbox, the slurry will be uniformly and stably transported to the running surface of the forming wire. The pulp stream is filtered and dewatered on the wire to gradually form a continuous wet web. The net case parts are mainly provided with case rollers, vacuum suction boxes, couch rolls and other forming parts. When the wet paper web formed on the wire case is dehydrated to a moisture content of about 20%, it can be peeled off from the wire surface and sent to the press section for further dehydration.

The press section is composed of several sets of roller presses, and the wet paper web is supported by the press felt and is dewatered by mechanical extrusion between the press rollers. In order to maintain the good dewatering performance of the press felt, the upper press roll is equipped with a felt washing device. After the press section, the dryness of the wet paper web is generally about 40%.

The wet paper web after dehydration in the press section needs to be further dehydrated by heating and drying. The drying section of the paper machine consists of many drying cylinders, which can be heated from the inside by steam. The paper web is pressed tightly on the cylinder surface to improve the heat transfer efficiency. After thorough drying, a calender consisting of 6-8 rolls is used to improve the overall web surface quality.

The above is the specific content introduced by the editor of China Paper Industry Network. After reading it, you should have some understanding of the working principle of the paper machine. The appearance of the paper machine is the product of technological innovation, and it is also the embodiment of the wisdom of the people.