Paste net means that there are pieces of holes on the surface of the mesh that are blocked and cannot be filtered. Paste has a great influence on the formation and dehydration of paper sheets and normal papermaking. When the paste web appears, the paper stock around the paste web is filtered and set in the first place after the paper is on the Internet. The thickness of the pulp layer becomes thin. The paper stock at the paste net flows to the surrounding area, and the paste surface becomes a thin paste area or not. In the pulp area, it finally becomes a curtain or hole on a sheet of paper.

　　Common types of pasting nets are star-shaped white dots that are generally distributed on the surface of the net, and each small white dot blocks 1 to 4 meshes. It is also strip-shaped, with a length of about 20-30 mm and a width of about several holes. Also in the shape of the mesh joints by the star-shaped white paste into a certain width and density of the bar.

　　The main types of substances that block nets are the following types:

　　1) Mixture of fine fibers and non-fibrous qualities. When calcium carbonate is used as a filler, a mixture of yellow viscous calcium carbonate and fine fibers can cause a paste web phenomenon. Summer temperatures are high. If free rosin compounds with high freeness are used, the phenomenon of agglomeration and sticking of the rubber occurs easily.

　　2) The resin block, if using a wood pulp with a high resin content, the phenomenon that the resin block sticks to the net occurs.

　　3) Asphalt blocks, white wax spots, plastic spots, oil stains, rubber blocks, paint spots, etc. mainly appear in paper machines using waste pulp containing these impurities as raw materials.

　　Paste web not only affects the quality of paper, but also has a great impact on production. Often due to sticky webs, it has to be shut down and even shut down a few times in a shift. In the worst case, the material of the paste web is not processed at all and has to be replaced. steel.

　　Paste the network can be used to deal with the following measures:

　　1) Treatment of webs caused by non-resin barriers

　　a) When the paste web appears, the vacuum degree of the vacuum suction box should not be too high, preferably lower than normal. If the total vacuum is lowered to make the moisture of the wet paper sheet too high to affect the normal papermaking, only the first and second vacuum boxes can be reduced. The degree of vacuum; b) proper tensioning of the forming network, for the elimination of the pit bag on the net, paste the net at the offset and to eliminate the paste at the net joint is often effective; c) to strengthen the net washing in the return process of the forming net, Especially the swinging high-pressure cleaning water system should be normal, and the pressure should reach 20~25kg/cm2; d) When the pasting net is found, the foam in the front net box should be promptly removed, because the foam often has a higher content of alcohol - stupid extractions, Foams often cause paste webs when they go online with paper stocks.

　　In addition, when the temperature is high in summer, it is appropriate to reduce the freeness of rosin size, reasonably control the dissolution and addition of calcium carbonate, and prevent the formation of yellow sticky substances.

　　2) The following measures can be applied to the paste web caused by resin barriers:

　　a) Reasonably control the resin content of the pulp, which is the most basic measure; b) Reasonably control the pH, use the alum to control the resin barrier;

　　c) Strengthen the cleaning work, regularly scrub the pipelines, beaters, storage tanks, and various slurry tanks to prevent too much resin accumulation. If they fall into the paper stock, they will cause a paste web on the paper machine; d) Use resin dispersants and The fixing agent disperses and removes the resin.

　　3) When waste paper is used as a raw material, it is necessary to strengthen the treatment of waste paper to prevent the inclusion of impurities such as asphalt and plastics.

　　When the web is pasted, steam is generally used for purging, and asphalt, rubber blocks, oil stains, and paints can be cleaned with organic solvents (such as gasoline or kerosene).

　　Under normal circumstances, do not use acid treatment of the forming network, because the acid corrosion of the network cable is not smooth, easy to hang on the fiber, more heavy paste network phenomenon.

　　In general, the forming network joints are easily treated with paste and are also treated with chemicals during welding, which is related to the fact that the cable is not smooth. Sometimes, the paste web caused by the binding of fine fibers, resins, and CaSO4 precipitates can not be washed away with acids, alkalis, benzene, etc., and copper ammonia solution can be used to dissolve the small fibers therein, and good results can be obtained. Pay attention to the application of a large number of clean water after processing, so as not to corrosion the forming network.

　　For the washing of plastic nets, use 10% or less caustic soda solution or 5~10% hydrochloric acid solution (note that the concentration cannot exceed 10%) or other cleaning agent. When washing, all damp water and washing water should be turned off. Wash at the speed of the crawler. Rinse thoroughly with clean water after washing. If nets are used, high-pressure clean water and steam injection are generally used to clean the dirt on the net. They can also be washed using the chemicals mentioned above.