The dust bag is also called the filter bag, which is called the heart of the dust removal equipment. The selection of the filter bag is very important, and it directly affects the dust removal effect of the dust collector. The selection of filter cloth bag (dust removal filter bag) is selected from the following aspects: gas temperature, humidity and chemistry; particle size; dust concentration; filter wind speed; dust removal method and other factors are comprehensively considered.
1. Matters needing attention when using dust bag:
In the use of the dust bag, it is necessary to prevent the gas from cooling below the dew point in the bag chamber, especially when using the bag filter under negative pressure. Because the shell often has air leaking in, the air temperature in the bag room is lower than the dew point, and the filter bag will be damp. As a result, the dust is not loosely attached to the filter bag, but sticky, blocking the fabric holes and causing cleaning. The ash failure causes the pressure drop of the dust collector to be too large and cannot continue to operate, and some paste bags can not be dusted.
To prevent the condensation of dust removal accessories, the temperature of the gas in the dust collector and its system must be kept higher than its dew point 25～35℃ (for example, the dew point temperature of the kiln-grinding integrated machine is 58℃, and the operating temperature should be above 90℃) , In order to ensure the good use effect of the filter bag. The measure is to take appropriate heating measures. For example, installing far-infrared electric heaters and electric heaters in the dust collector, or adding a radiator in the bag room, can appropriately increase the flue gas temperature of the host. Strengthen the temperature monitoring of the dust collector and the dust removal system in order to grasp the operating conditions of the bag filter and prevent condensation.
2. Precautions for the processing and production of dust-removing cloth bags:
Too long cloth bag will cause the lower part of the filter bag to wear, especially if the bottom of the bag is within 100 mm, the main reason is that the length of the dust removal bag exceeds the length of the cage by more than 30 mm. The filter bag shrinks too much during filtration, and the bottom of the filter bag is 100 mm upward. It will rub against the bottom of the bag cage and eventually wear the bag. The damage marks are mostly from the inside to the outside, and are damaged at the bottom of the bag.
The bag spring ring is related to important links such as the sealing and load-bearing of the filter bag. The spring leaf breaks mostly occur when the dust bag is not stored properly. The spring leaf is oxidized and rusted or the spring leaf is too hard and brittle. The former belongs to the customer and the latter belongs to the supplier. . If the spring leaf is too soft, there is no problem as long as it does not affect the installation of the filter bag. If it cannot be installed, it needs to be replaced by the supplier.
Most of the sewing thread breaks are caused by wear, and there are obvious signs of wear on the broken surface. It is also caused by the different materials of the sewing thread and the filter bag, but the probability of this occurrence is extremely low, and the fracture surface is pulverized or the strength is reduced.
3. Inspection of cloth bags: Inspection of filter bags: professional inspection tools and perfect quality inspection system to ensure the quality of each dust-removing cloth bag. Due to the increasingly fierce competition in the filter material market, many manufacturers have made great discounts in terms of quality. We hereby remind users to pay attention to the following matters when ordering dust collector bags.
Dust removal cloth bags require many processes from raw materials to finished products, and each process needs to be strictly controlled. If quality problems occur in the filter bag, it usually occurs in the filter bag raw material, bag mouth diameter, filter bag length, bag mouth spring ring, and sewing thread.
The wrong use of dust bag materials is the supplier's lowest level of error, but there are also a few suppliers who use it in order to save costs. All filter materials on the filter bag should be made of the same material, or high-grade materials can be used instead, but not low-grade materials. For example, it is possible to use PTFE sewing thread for PPS filter bags, but not to use glass fiber sewing thread.
The size of the bag mouth diameter determines the airtightness of the filter bag and the porous plate. When processing a new filter bag, the supplier and the customer must communicate well to avoid errors. If the diameter of the bag mouth is too large, the filter material can be cut at an equal distance at the groove of the bag mouth. The cut length should not exceed 20 mm. Reduce the outer diameter of the bag mouth for installation. If the bag mouth diameter is too small, you can wrap 300～400mm edge strips of the same material at the bag mouth. The length of the edge strips is adjusted according to the tightness of the installation bag mouth.