The production process of mica paper

The production process of mica paper is: storage tank - net section copying and forming - press section dewatering - drying section drying - Rolling paper into tubes.

1、Net copying and forming

The mica pulp in the storage tank is diluted with water that meets the quality requirements to a concentration of 2% to 3%, and the extracted pulp is pumped from the pulp into the net section of the paper machine, where it is further diluted to a suitable concentration (generally between 0.3% and 0.7%) according to the requirements of different thicknesses of mica paper.

2、Press section dewatering

Mica paper machine press section consists of vacuum suction box, press roll, felt guide roll, tensioning roll and press roll. Before entering the press, the wet mica paper is dewatered in the vacuum suction box to cut down the moisture when entering the press.

The mica paper is subjected to considerable linear pressure in the press section, which not only removes water (about 0.7% water after two stages of pressing), but also reduces the gap between the mica scales of the laminated paper sheet, so that the mica scales forming the mica paper are closely packed, thus improving the electrical function and tensile strength of the paper.

The felt used to make mica paper is called paper felt, which is circular in shape, and its effect is that: the active pressure roller drives each roller of the web and press section to run in the felt one after another and keep it at a suitable speed; the mica is wetted using the effect of the felt whose specific surface area is much larger than that of the circular grid. The tires are attached to the felt and sent to the press section for dewatering, where the felt absorbs the water and then filters and discharges it.

3、Drying of mica paper

The drying of mica paper in the production process is to remove moisture and make it a kind of insulation material with suitable dryness for electrical appliances. To ensure the insulation function of mica paper, the moisture content of the finished paper should be between 0.2% and 0.5%.

The drying of mica paper machine is composed of upper and lower two drying cylinders, drying rollers, steam pipes and transmission section.

During the drying process of mica paper in the drying section, more water vapor will occur because of the evaporation of water. If it is not discharged from the workshop in time, it will condense into water droplets, which will not only reduce the drying power, but also the water droplets will cause spots or holes on the paper. Thus, it is necessary to install ventilation equipment, timely exclusion of steam occurring in the drying process.

4, mica paper coiling

Mica paper winding is a process in the papermaking process. Paper winding is completed by the paper machine, its effect is to paper machine finished paper rolled into a cylinder for slitting and rewinding.