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1. Pulping worker: Always check the water level of the headbox and whether the pulp discharge port of the pulping box is blocked (or whether the concentration tester is operating normally) and timely control the gram weight of the paper to ensure that the quantification meets the production standards and product quality.
2. Lead the whole class of workers to produce safely, and must not violate the operating procedures to ensure safe production.
3. Responsible for the handling of technical problems of the whole machine and the handling of equipment paper defects. Those who cannot handle major problems should report to the factory office for instructions in time.
4. Blanket workers: You should always check the operation of each roller of the blanket, and check whether the blanket is rotten and scratched. If any problem is found, deal with it in time to keep the blanket in normal operation. Paper defects such as crushing and wrinkling.
5. The blanket should not be discounted, too tight or too loose. Keep the blanket tight and moderate. When the blanket deviates, use the blanket adjuster (automatic screen guide) to adjust the blanket roller when it is involved in the sundries and pulp blocks. dig out to prevent getting involved in the blanket and causing personal accidents.
6. Gas watcher: Master the air pressure and humidity curve of each cylinder group according to the process regulations. If the air pressure of the drying cylinder of the paper machine changes, if the air meter fails, the air should be stopped in time to replace the safety valve of the air pressure meter. Once the safety valve is set, it is not allowed to adjust and overpressure. production to ensure the safe use of the dryer.
7. A steam-water separator must be installed at the drain outlet of the drying cylinder to automatically discharge the condensed water in the cylinder.
8. The surface of the drying cylinder should be kept clean, the surface of the cylinder should not be stuck with impurities, and the drying cylinder and the scraper should be kept in good agreement. If the vehicle is parked for more than 2 hours, the air should be slowly boosted after driving to prevent the drying cylinder from expanding and cracking during the heating process. .
9. During the normal production of the paper machine, it is necessary to check the operation of the machine frequently. If the bearing or roller is found to be hot or vibrated, it should be dealt with in time.
10. The main production parts in the paper machine: drying cylinder, idler, couch roll, press roll, and key parts of the wire section, care should be taken to protect them during operation, and their surface flatness and appearance should not be damaged. The quality life of the above parts is damaged due to improper operation The whole machine will be produced.
When we move up and down the knife bed of the A4 paper cutter, Guo Zengzhong, it mainly relies on the pull rod with the adapter sleeve to trigger its action. To ensure the safety of the machine in the case of accidental overload, we can configure it on the pull rod Corresponding secure pin parts. But sometimes when the resistance value of our cutting action is large, the safety pin will crack. At this time, to ensure the safety of the machine and other corresponding parts, we should stop the cutting operation immediately.
Sometimes when we use the A4 paper cutter to cut some of the discarded label paper, due to the unevenness of the paper, it is too full during the horizontal placement process, and at the same time it is too close to the right wall panel. At this time, when we cut it, its knife bed will cause its stable pin to crack instantly due to the excessive resistance value. At this time, we can only replace the accessories accordingly, but in fact, it is very troublesome to stop and replace the accessories.
Therefore, in order to avoid the occurrence of the above accidents and to avoid some unnecessary troubles, we should pay special attention to its high consistency while cutting some relatively narrow paper rolls, and at the same time make it not too close to it. Right wall panel.
Our country’s paper machine branch transmission equipment used SCR DC speed regulation in the past. Due to the existence of slip rings and carbon brushes, the reliability and accuracy of the paper machine are not high, which leads to the backwardness of the paper machine machinery and the speed is only about 200m/min, which is difficult. Compared with foreign high-speed paper machines of 1000m/min. From this point of view, the frequency conversion of the paper machine branch transmission machinery is the general trend.
Divisional transmission involves many transmission points such as the wire section, press section, front dryer, rear press, rear dryer, calender, etc. of the paper machine. Because the paper has the shortcomings of thinness and fragility, in order to prevent the paper from breaking , Curl, wrinkle, indentation, high-precision speed control must be carried out on each transmission point, and the paper must be stretched according to the stretch rate limited by the direction of the paper. In other words, in the whole process from sizing to winding, the paper web must be cascaded at a certain speed, so that there is tension.
It is the frequency conversion control based on the sub-drive that emphasizes the on-line stepless speed regulation and synchronous following performance of each transmission point. Therefore, the frequency converter used in the sub-drive must have the following characteristics:
1. The speed range is wide, and the efficiency must be above 90% in the full speed range.
2. The power factor is higher than 0.9.
3. The total distortion of the input harmonic current is less than 3%.
4. Adopt standard IGBT with high reliability and mature technology.
5. It can reduce the output harmonic components and effectively reduce the effect of dv/dt noise and torque ripple.
6. Use the communication function to realize high-speed serial transmission of data.
For example, the power of the 4 branch transmission points of a 1092 tipping paper machine in a paper mill is 11kw for pressing, 11kw for main cylinder, 7.5kw for group cylinder, and 5.5kw for roll paper. Another example is the 2820 kraft boxboard paper machine of a certain factory. The frequency converter adopts the American AB company 1336 type high-function frequency converter, the PLC adopts the AB company SLC500 series, and the operation interface adopts a touch screen. The upper computer controls the storage of operating parameters, the automatic generation of data tables, the automatic printing of production reports, and the analysis of fault alarm status. The network communication adopts the international PROFIBUS DP communication network. The motor adopts AC variable frequency motor, and uses magnetic flux vector closed-loop control. In addition, the load distribution of each transmission point can be controlled by calculating the actual power used by each transmission point, and in the production process, local tension and relaxation can be performed without affecting the speed chain by inching.
The above two examples are more typically applied to the control principle of the divisional frequency conversion control. The control principle of the divisional transmission is to maintain the speed cascade and high-speed transmission. The former uses the upper computer (PLC or industrial computer) to calculate the speed cascade. The latter is achieved through the high-speed serial communication capability of the inverter itself. In this way, the entire system has simple wiring, high degree of automation, rich information and compatible interfaces, which facilitates the integration of FA and management and control.
The result of the speed cascade is to form a series of speed chains for the main transmission points of the paper machine subsection transmission. As long as the speed of one of the points is adjusted, each subsequent transmission point is also adjusted quickly. In the actual paper machine control, it is often necessary to add a specific transmission control method according to a specific position, especially the important parameter load ratio control.
The so-called load ratio control means that in order to maintain the tightness and reasonableness of the contact between the two intermeshing rollers, the load distribution of the two rollers is required to achieve the best effect. In the control of the engagement rollers of the press section of the paper machine, the calender, etc., according to technological requirements, when the paper web breaks, the two engaged rollers are in the disengaged position, and the two rollers are in the closed position when the paper web passes. Among them, in the meshing roller closing, in order to maintain the close contact between the two rollers on the machine maple and meet the meshing requirements, a load ratio control method is required.
The main drive of the meshing roll of the paper machine still adopts the speed cascade control mode, and the secondary drive adopts the load ratio control mode. In this load ratio control, the speed closed-loop setting value is added to the main drive setting value (V setting), and the speed is increased by 5%. In this case, the output value of the speed loop is that of the current loop. The set input value (M setting) will increase, and then the output value of the main drive speed loop is multiplied by the load ratio percentage value to limit the set input value (M setting) of the secondary drive current loop, and it will be tight. Keeping up with the main drive makes the meshing degree of the two rollers closer and closer.
Papermaking, especially the papermaking technique improved by Cai Lun in the Eastern Han Dynasty (also known as "Cai Du Hou paper"), is a revolution in writing materials. It is easy to carry and widely used. It promotes the cultural development of China, Arabia, Europe and even the whole world.
The spread of paper in China has a complex and long history. As a carrier of cultural communication, Chinese culture has a long history. Therefore, paper has an important historical position in China. Paper burning is a part of the traditional paper making technology, which is convenient for people's daily life.
At present, the main raw materials of burning paper machine are bamboo, waste paper and other renewable plants, and their industrial and commercial values are generally recognized. Other raw materials used in the production of paper-making machine are gradually used to reduce the consumption of wood and other materials, which meet people's daily demand for paper, and are also the development direction of the paper machine industry Know the direction.
The BOB press felt has the good capability of filtration,drainage.High tensile strength and drying section (MG felt) of ecumenical paper machine to make lower/medium quality paper.The BOB press felt has good size stability of CD and MD,good filtration/drainage and good strength for all ecumenical,The BOB felt for striation paper can be designed of different striation on the paper surface for client’s special requirement,good third dimension on the surface,have good filtration/drainage and long life.
BOB press felt Characteristics
1.100% polyester
2.High efficiency
3.Good filterability
4.Small elongation
5.Easy to wash and clean
6.Long service life
7.International standard quality
BOB press felt
Applicability
1.Paper making dryer felt is made up of single base layer fabric and fiber layer. Base layer is woven from synthetic filament or multi-filament.
2.The structure of paper making dryer felt is designed base on different paper machine, different press position and different type of paper. Fiber layer is consisted of different lap of fiber web and different diameter of fiber for the best trainability and fiber support index.
3.Paper making dryer felt has good quality properties such as less elongation, easy to wash, no-mark on paper, long life performance etc. and can be used in all different kinds of paper making machine to produce all different kinds of paper.
The sharpness and service life of the cutters of the A4 paper cutter greatly influence the production efficiency of this A4 paper cutter. The use effect and life of the cutting tool depend on four factors: the material of making the knife, the shape and angle of the sharpening knife, the quality of the sharpening knife, and the type of material being cut.
1. Material of knife making
The cutter of the single-chip A4 paper cutter is made of high-temperature insert welding of the blade and the blade body. The blade is made of high hardness chromium tungsten manganese steel, and the blade body is made of low carbon steel. The durability of the cutting tool is directly proportional to the hardness of the steel used for the cutting edge. High-quality blades, the hardness of the cutting edge after quenching can reach HR55~60.
Second, the shape and angle of the sharpening knife
On a single-sided A4 paper cutter, a single sharpened cutter is generally used, and the sharpening angle is between 19° and 23°. However, this shape of the sharpening edge is not an ideal shape. The beveled surface of the cutter is subjected to the pressure from the part of the paper stack being cut during the cutting process, so that under the friction of the paper edge, the bevel of the blade is very Will be worn out soon. The double-edged knife has obvious advantages. Its sharpening helps to reduce the load of the machine and improve the accuracy of cutting.
The smaller the sharpening angle of the cutting tool, the sharper the cutting edge, the lower the resistance of the cut object to the knife, the wear and power consumption of the machine are also small, and the cut product is neat and the cut is smooth. However, if the sharpening angle is too small, the strength and wear resistance of the cutting edge will be correspondingly reduced, and the cutting speed and cutting quality will decrease. Therefore, the angle of the sharpening edge should be as small as possible when the tool material permits and considering the magnitude of the shear resistance of the cut object.
3. Quality of sharpening
The quality of the sharpening depends on the production materials and equipment, the sharpening process specifications and the technical level of the operator. The higher the quality of the sharpening knife, the longer the service life of the cutting knife, the better the cutting quality.
4. Types of cutting materials
During the cutting process, the speed at which the knife edge becomes blunt is related to the wear resistance of the material being cut. When cutting paper, the speed at which the blade becomes blunt depends on the texture of the paper and how hard the ash content is. When cutting harder paper with higher ash content, the faster the blade becomes dull.
The above are the four major factors that affect the use of A4 paper cutter tools.
The pressure screen is widely used in the papermaking industry and is one of the important equipments in the papermaking machinery. It is a new type of recycled pulp screening equipment, a new generation of recycled pulp processing products. In order to produce better products and improve productivity, we must strictly follow the relevant operating procedures and precautions of the pressure screen. So what should be paid attention to when operating it?
1. Before use, be sure to check the joint of the pipe to see if it is connected properly, and whether the screws on the cover and the outer frame are tightened. If not, you need to tighten them, otherwise it will affect the normal use. Whether it is tight or not, and whether the pulley is tightened, it should be checked regularly to prevent the belt from slipping and causing the pulley to fall off.
2. The rotation direction of the pressure screen should be consistent. When rotating, the inner sealing water must be opened to check whether the rotation direction is smooth, and the safety cover of the pressure screen should also be placed in a suitable position.
All of the above should be noted. Before operation, it must be checked to ensure that there is no problem. This is to prevent the pressure screen from suddenly stopping during use, which will affect the smooth operation of the operation. Therefore, we must strictly follow the operation process of the pressure screen and related precautions.