Do You Know The Function of Paper Machine Forming Device

The function of the forming device of a paper machine:

The forming device, also known as the wire section, is the most crucial part of a paper machine. The paper stock suspension forms the paper sheet on it, and both the quality of the finished paper and the normal production of the paper machine are closely related to the operation of the forming device. Once the wet paper web is formed in the forming device, the interlacing state of the fibers in the paper is basically set, and the basic physical properties of the paper are also determined. Subsequently, processes such as pressing, drying, and calendering of the paper machine can only improve the properties of the already formed paper web to a limited extent. The forming device is also usually the most complex part of the paper machine. During operation, the power consumption and maintenance costs of the forming device account for a considerable proportion of the entire paper machine.

The main functions of the forming device of a paper machine are as follows:

1. Obtain a well-organized wet paper web

The formation of a paper web is a complex process, which can generally be viewed as the result of fibers gradually depositing onto the surface of the forming fabric and intertwining into a thin layer. To obtain a uniformly structured paper web, in addition to requiring well-performing flow equipment, it is also necessary to enable the paper stock to undergo a reasonable dewatering process on the forming fabric surface. Generally, by controlling the difference between the wire speed and the pulp feeding speed, shaking the wire table, and selecting appropriate dewatering components, the fiber suspension can be made to be relatively calm yet have a certain degree of turbulence during the paper web formation process, thereby ensuring that the deposited fibers are evenly distributed without flocculation. At the same time, excessive and undue rapid dewatering should be avoided, as this can lead to excessive loss of sizing materials, fillers, and fine fibers in the paper stock, resulting in differences in properties between the two sides of the paper web.

2. Dewater the formed paper web to a certain dryness level

After the wet paper web is initially formed, it generally requires forced dewatering methods (such as vacuum suction and pressing) to achieve a certain dryness or wet strength, so that it can be peeled off from the forming fabric surface.

The commonly used paper machine forming devices include fourdrinier paper machine former, cylinder mould paper machine former, sandwich paper machine former, composite former, high consistency forming device and drying forming device.