Operating procedures for starting and stopping the press section of a paper machine

(1) Key points of start-up operation of the press section of the paper machine:

1. Check whether all parts are in good condition, evacuate useless bolts, tools and other sundries to a safe place, check whether the automatic guidance of each bed blanket is in good condition, the adjustment is sensitive, whether the adjustment direction is correct, adjust the position of the rear baffle and the working air pressure.

2. Close the scraper of each roll, check whether the scraper is in good condition with the surface of the roll, and open the scraper of the press roll to spray water.

3. Check whether each suction box plate is clean and smooth, seal the end sealing plate of each suction box, and adjust the suction width of each suction box.

4. Pull out the blankets, check carefully, and remove the sundries in the blankets, and properly tension the blankets. (Subject to the fact that the felt does not fold when it rotates with the drive roller)

5. Open each low-pressure water pipe to wet the blanket.

6. When closing the press roll (including the squeezing roll), in the process of closing the nip, carefully check whether the front and rear sides of each nip are closed synchronously and whether they are closely matched. Find the cause, troubleshoot, and start the press section when the nip is not fully closed.

7. Start the vacuum pump.

8. Send the power-on signal, and after confirming that there is no one in the danger, start the press section to crawl.

9. Tension the blanket to the production requirements and put it into automatic tension control.

10. After each roller and the felt are running normally, change to fast.

11. During fast running, adjust the standard line of the blanket and adjust the running position of the blanket.

12. Start the blanket roller scraper of each bed and the blanket high-pressure water spray pipe to check whether it is normal.

13. When the felt is running fast and the vacuum pump is turned on, the cleaning water inside the vacuum feeding roller and the vacuum pressing roller can be turned on to clean the inside of the rollers. Otherwise, the cleaning water must not be turned on and must be turned off before receiving paper.

14. Open the high-pressure mobile water spray pipe to clean the blanket.

15. Pressurize each nip in turn, adjust the pressure according to the process requirements, and pay attention to the same pressure on both sides.

16. After confirming that everything is in good condition, the paper pick-up operation can be carried out.

(2) Main points of production operation of the positive belt in the press section of the paper machine:

1. Frequently check the operation of the equipment belonging to the press section, and deal with any abnormality in time.

2. Regularly check and adjust the speed ratio of the wire section and the press section, and the change of the tension of each press.

3. Always check the pressure on both sides and the current load of each roller, and adjust it to meet the technical requirements when any deviation is found.

4. Regularly check and adjust the tension of the blanket, the running condition of the blanket, and the sensitivity of the blanket adjuster.

5. Regularly maintain the cleanliness of the press roll and scraper.

6. Always check whether the felt rolls are wrapped with pulp, and rinse with water carefully.

(3) Key points of the shutdown operation of the press section of the paper machine:

1. After receiving the shutdown instruction, when there is no paper on the blanket, open all the high and low pressure water spray pipes to clean the blanket.

2. Rinse the surface of each roller with water, and each fixed scraper moves the scraper to wrap the material and the suction box.

3. After the blanket is cleaned, stop the high-pressure water spray pipe of the blanket.

4. Stop the swing of each roller scraper and stop the vacuum pump.

5. Stop the transmission of the press section. When the press section is shut down for a long time (more than 4-6 hours), especially when 100% synthetic fibers are used, 3-4% of the running length of the felt should be relaxed to prevent excessive tension concentration.

6. Close all water spray pipes, lift up each press to prevent crushing the felt and crushing the lower rubber roller.

7. Lift the scraper of each roller to wash both sides of the press and the pipeline on the table.