How to Do with Air Leakage of Nomex Filter Bag
Nomex filter bags often encounter some puzzles and problems in the process of operation. Air leakage of dust collector is a common problem. Air leakage will not only reduce the whole dust removal effect, but also directly shorten the service life of Nomex filter bag dust removal cloth bag.
In order to prolong the service life and dust removal efficiency of Nomex filter bags, air leakage must be prevented. Here are two effective methods to prevent air leakage:
Strengthen sealing
(1) Strengthen the sealing of dust removal system: to prevent air leakage, it is also necessary to strengthen the sealing of rigid impeller tripper, inlet and outlet valves, conveying equipment, pipelines, inspection doors and other equipment, so as to reduce and eliminate air leakage.
For example, to improve the machining accuracy, all joints of shell and pipeline must be continuously welded without air leakage and desoldering; The joints of valves, ash unloading and ash return equipment shall be padded and firmly connected with fasteners without air leakage.
(2) Strengthen the sealing of manhole door: the design of manhole door cover plate shall meet the strength and stiffness requirements. The door frame and door cover plate must be flat during fabrication. During assembly, sealing strip shall be used for sealing, and the door shall be compressed with pressure block.
Common sealing strip structures are 'U' and 'y'.
(3) Strengthen the sealing of the back blowing valve: the ash cleaning energy of the back blowing Nomex filter bag comes from the back blowing machine. In order to protect its motor and avoid frequent opening, the back blowing machine is generally set to the normally open state. If the back blowing valve is not tightly closed, the positive pressure gas generated during the operation of the back blowing machine will be continuously blown into the bag chamber during the non ash cleaning period, Seriously interfere with the normal filtering work of the dust collector.
The main manifestations are: increased continuous working resistance caused by air leakage; During ash cleaning, due to air leakage of several other anti blowing valves and energy dispersion, the ash cleaning energy in the ash cleaning bag room is insufficient, affecting the ash cleaning effect.
In order to improve the operation efficiency, it is recommended to seal the reverse blowing valve with a sealing ring.
Optimized design and installation
The volume of pulse Nomex filter bag in rotary kiln is huge. In order to facilitate transportation, it is usually made by disassembly, split shipment, on-site assembly and so on.
Improper on-site installation is easy to cause up and down dislocation of equipment, and forced installation is easy to produce local deformation, uneven weld, etc; After the equipment is put into operation, under the combined action of wind power, ash cleaning power and thermal stress, the above defects are easy to form high stress concentration, resulting in local cracking and air leakage of the equipment.
In the design of dust collector, in addition to considering that the equipment body has sufficient strength and stiffness, the installation procedure shall be optimized to minimize the cumulative installation error and improve the installation quality.
