Paper Machine Clothing

About polyester forming fabric

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1.Features
1.1 Long life, wear resistance, low consumption
1.2 High fatigue strength, acid resistance, weak alkali resistance
1.3 Light traces, good molding quality
1.4 Lightweight, easy to transport, easy to use
2.Selection
2.1 Type: It should be based on the use of plant equipment, processes, paper types, pulp and other conditions to choose the appropriate type
2.2 Length: 0.5% elongation of the polyester forming fabric during use. When selecting the length, the shortest dimension that can be installed on the machine should be taken.
3.Installation
3.1 Before installing the mesh belt, check whether the equipment is in good condition.The parts that come in contact with the net are forbidden from unevenness, slanting, sharp hairs, sand, etc. The guide system must be flexible.
3.2 The direction of operation must be in accordance with the direction of the arrow on the mesh belt, place the mesh belt in the correct position, and the rollers are parallel to each other to prevent the nets from being deflected.
3.3 There should be a swinging high pressure water device that flushes the mesh belt. Medium and low speed paper machine water pressure is not less than 6-10kg/cm2, speed exceeds 350m/min, water pressure is not less than 10-15kg/cm2, when using multi-layer forming nets, water pressure requirements 15-30kg/cm2. Water should be clean and without sand.
3.4 When installing the mesh belt, first slightly tension the net, add water to lubricate and run. After the sizing, pay attention to adjust the tension of the net to the normal level, the tension of the low speed paper machine is kept at 3-4kg/cm2, and the tension of the medium and high speed paper is kept at 4-6kg/cm2.
4.Using
4.1 At the beginning of operation, natural elongation will occur. During the first 1-2 days of operation, we must pay attention to adjust the tension of the mesh at any time to reach the standard, maintain the tension, and stabilize the mesh after 3 days of operation.
4.2 In the process of use, it is necessary to use high pressure water spray and clean the net in time, and turn off the high-pressure water in time when shutting down, so as not to damage the mesh.
4.3 When large area flushing, use 5% alkaline solution or 10% acidic solution, wash with a soft-bristle or nylon brush, and wash with water after washing.
4.4 When the machine is shut down for a long time, the mesh belt must be relaxed, and the suction system must be stopped. If you need to repair the paper machine in the middle of use, you should carefully retreat the mesh belt. When installing the mesh belt, it must be installed according to the original running direction.
5.Storage
5.1 Polyester mesh is made of high molecular organic material and should be stored in a dry environment at room temperature, avoid high temperature and humidity.In order to avoid mesh deformation, storage time should not be too long.
5.2 When the storage temperature is too high or too low, it should be stored in the production workshop for two to three days prior to use to avoid length dimensional changes.
6.Precautions
6.1 When installing or removing, it is necessary to properly protect the mesh, and avoid creases caused by mesh belt damage and extrusion.
6.2 The mesh is strictly prohibited from dry grinding, or ditch or slip due to inappropriate tension.
6.3 The mesh is strictly prohibited from turning over, otherwise it will wear out quickly.
6.4 Do not flush the mesh with high temperature steam or brush with a metal brush.
6.5 Fireworks and high temperatures are strictly prohibited.

Paper Machine Clothing

Problems and Causes of Problems during the Use of Papermaking Machinery Forming Fabric

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1.Mesh belt edge wear too fast:The vast majority of paper-making machinery is worn out at the joints with vacuum and no vacuum (10-15cm mesh edge).
Solution:1.Try to increase the width of the vacuum box opening.
2.Add atmospheric lubrication water to the edge of the real empty box.
3.Add a reinforcing rib to the appropriate position.
4.Check whether there are edges or gaps in the side wiper and the real empty box. In particular, the joints of the ceramic panels are weak.
5.Check whether there is serious wear on the edges of the rolls(After the roller wear, the diameter of the roll becomes smaller and the tension of the net is smaller than that of normal mesh, which further accelerates the wear.).
2.Overall wear:
1.The quality of the panel is unqualified.
2.The tension of the net is small, and the backhaul tension of the single-layer fabric is 3-4kg/cm, and the backhaul tension of the forming fabric is 5-6kg/cm.
3.Poor pulp quality.
4.The high air pereability of mesh causes the loss of pulp, and there are too many filler particles between the mesh and the real empty box panel, which will also speed up the overall wear of the mesh.
5.The low permeability of the mesh allows the vacuum to increase and the wear is accelerated.
6.The roller speed and the mesh speed are out of sync.
7.The speed of the mesh is not synchronized.
3.Local wear out too quickly:
whether the molding board, wiper board, vacuum box panel has the wrong stubble, uneven and the gap;
whether the rolls have local wear and corrosion.
4.Local bulge:
whether the molding board, wiper board, vacuum box panel has the wrong stubble, uneven and the gap;
chest roll vacuum roller whether there are solder joints and other protrusions, whether the rubber roller has impurities.
5.Guide roll wrapped slurry:
the cleaning water pressure is low, the mesh internal fiber is much;
the mesh air pereability is low;
there is a problem with the cleaning method. The two and half nets should clean the paper surface of the net, the nozzle is blocked, and the best distance between the nozzle and the net is 15-20cm.
6.The pulp in the vacuum box is too full:
Insufficient air permeability;
Short pulp fiber causes a lot of loss;
The retention agent has poor quality or little addition.
7.The mesh belt runs with a wide range of movement: The corrector is not working properly and the mesh is not straight.
8.The net becomes narrow after being used for a period of time:After running for a period of time, the line deflection (the local network operation is inconsistent) is due to the local wear of the molding board, the wiper board, the real empty box panel or the guide roller.
9.The comparison between the type D and the life of the previous mesh:D-type can effectively solve the two sides different of the paper, accelerate the dehydration and improve the speed, but the life of the forming fabric will decrease, the main reason is that the waterline is shortened and the wear speed is accelerated. Life expectancy is down by a third or even a half.