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Past and Present Situation of Domestic Paper Machines

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Past and Present Situation of Domestic Paper Machines

  As we all know, the invention of paper is one of the four great inventions in China, which has a long history in China. So far, in some remote areas, the ancient method of papermaking is still popular. And it has been sought after by some enthusiasts.

  In 105 AD, Cai Lun summarized the use of linen fibers in papermaking since the Western Han Dynasty. Using bark, hemp head, rags, old fishing nets and other raw materials, he improved the papermaking process, marking the beginning of the papermaking machine.

  In the eighteenth century or so, paper-making technology has been further developed in Europe. It has been further improved and developed by the Netherlands, France and the United Kingdom. It has developed into the familiar concept of paper-making machine, long net paper-making machine and circular net paper-making machine.

  After nearly 200 years of development, in the early 20th century, paper machine has become a large, high-yield industrial machine.

  Since the 1950s, more development and innovation have been made in papermaking machinery. For example, vertical continuous cooking, displacement scrubber, hot rolling mill, new pressure screen and slag remover have appeared in pulping equipment. In papermaking machines, new types of pulp boxes, grippers, composite machines, polyester forming nets and so on appear. There are many kinds of technologies.

  After the 1960s, the controllable DC motor speed control system began to be widely used in papermaking machine. Electronic technology was used to detect, control and record papermaking process parameters, such as machine speed, concentration, temperature and flow rate of materials, drying, quantitative, board thickness and so on. By the 1980s, large vertical continuous digesters could produce more than 1,000 tons of pulp per day. Paper width can reach 10 meters, speed more than 1000 meters per minute, daily output also exceeds 500 tons.

  Up to now, with the development of science and technology, the performance of paper machine technology has been further improved. The maximum daily output is close to 2,000 tons, and the year-on-year data have doubled.

  However, with the development of energy-saving, environmental protection and new technology, the future development direction of paper machine will be to develop towards large-scale, highly intelligent and high utilization rate. The pursuit of quality and efficiency will further enhance the development of paper machine.


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