Main faults and avoidance methods of air filter bag

1. Burning: The main reason for the burning of the dust collector bag is that the initial layer thickness on the surface of the dust collector bag is not enough, and the temperature of the flue gas is too high. If the temperature of the flue gas treated by the dust collector for a long time exceeds the working conditions of the bag, it is easy to harden and shrink the dust bag or melt and cause holes. If the thickness of the initial layer is not enough, sparks in the flue gas will flow in, or the dust will heat up, which may also cause the dust bag to burn out the holes. The burning of the dust bag is mainly reflected in the newly replaced dust bag online. Since no pre-coating is performed after online replacement, the high-temperature flue gas carries sparks and directly touches the bag, which is easy to burn and damage the dust bag.

2. Wear: The wear of the dust removal bag mainly occurs in the middle part of the dust collector, and on a single dust removal bag, it mainly occurs within 1 meter of the bag from the outlet. The main reason is the uneven distribution of flue gas, the high flow velocity in the middle of the single chamber, and the excessively high filtration gas velocity at the outlet of a single dust bag, which causes dust to impact and wear the bag, and also causes the fabric fiber tension of the dust bag to be affected. damage, it is easy to perforate local bags, and the service cycle is too short. It is recommended to add a protective layer or replace with a more wear-resistant cloth bag for the dust bag that is frequently worn.

3. The distance between the dust removal bags is too small, and the skeleton is bent, which may easily cause wear between the bags. If the clearance between the bag and the skeleton in the diameter direction is too small, the cleaning effect will be poor, which will shorten the cleaning cycle and increase the pressure of the air injection; wear. Special attention should be paid to the characteristics of some filter cloths that change greatly with temperature and have elongation characteristics.

Fourth, when there are holes or burrs in the welding of the skeleton, or the rough surface caused by corrosion, the wear of the cloth bag will also be accelerated. The bag and the hole of the flower plate are not tightly sealed, which will cause the wear of the anti-fold at the top of the bag.

5. The misalignment of the venturi or pulse tube relative to the cloth bag will easily cause the air flow from the blowing pipe to directly wash the upper section of the cloth bag and cause wear. If the bag is cleaned too frequently, it will accelerate the wear of the bag.

6. Excessive filtration air velocity will break the initial dust layer, and the dust will impact the cloth bag and cause excessive wear. If the cleaning frequency of the cloth bag is too high at this time, the fabric of the cloth bag will be loosened and the wear of the cloth bag will be accelerated. The dust contained in the flue gas exceeds the design standard, which will also accelerate the wear of the cloth bag. Too much dust accumulation in the small ash hopper will cause the flue gas in the flue gas chamber to contain too much dust, which will also accelerate the wear of the cloth bag.

7. Measures to reduce wear and tear: During the production process of the dust removal bag, thicken the weak parts of the dust removal bag; during the installation process of the bag, adjust and replace the bag whose distance is too small and the skeleton is bent; the dust removal bag and the skeleton are in the diameter direction. The matching should be appropriate, and the length of the skeleton should be slightly smaller than the length of the cloth bag; the skeleton should be strictly inspected before use, and the damaged skeleton should not be used; the dust removal bag and the perforated plate should be sealed tightly without leakage, and fluorescent powder can be used to check for leaks if necessary; Venturi and pulse tube are properly aligned. In the process of operation, it is necessary to prevent the factors that the filtration speed is too high, the cleaning cycle of the bag is too short, and the pressure of the compressed air is too high. When setting the pulse cleaning cycle of the dust collector, it is better to ensure that the dust collector works under a stable pressure and the set pulse cleaning cycle time is the longest; the pulse cleaning time can ensure that the initial dust does not fall off, set The shortest cleaning time is better; if the initial dust layer is insufficient, the cleaning period can be extended as compensation; if the pressure difference control is used, the stability of the inlet and outlet pressure setting of the dust collector can be improved.