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Brief introduction of vertical filter and replacement method of filter bag

Time:2019-11-15 08:48:49

Introduction to vertical filter:
The vertical filter (bag filter) is a kind of multi-purpose filter equipment with novel structure, small volume, simple and flexible operation, energy saving, high efficiency, sealing work and strong adaptability. It has many advantages, such as reasonable structure, good sealing, strong circulation ability and simple operation. In particular, the side leakage probability of the filter bag is small, which can accurately guarantee the filtering accuracy and quickly change the filter bag. The inner part of the filter bag is supported by a metal basket. The liquid flows in from the inlet and flows out from the outlet after being filtered by the filter bag. The impurities are intercepted in the filter bag. After the filter bag is replaced, it can continue to be used. Widely used in chemical industry, coating, ink, food and other industries.
1. Composition of vertical filter
The vertical filter consists of three parts: filter cartridge, filter basket and filter bag, with compact and simple structure.
2. Sealing structure of vertical filter
The vertical filter is sealed and locked by four sets of pendulum type ring head bolts to make the filter more able to withstand extremely high filtration pressure and water hammer type pressure impact.
Replacement steps of vertical filter bag:
1. Close the input valve. When there is pressure at the outlet, close the output valve.
2. After confirming that the pipeline connected to the exhaust valve has been connected to the safety place or the suction port (pay special attention to filter toxic and corrosive liquid), open the exhaust valve again to prevent the liquid from causing harm to the staff and pollution to the surrounding environment.
3. Check the pressure gauge to make sure the internal pressure is 0, and the vertical filter is separated from the pipeline system.
4. If there is a drain valve, confirm that the drain liquid is connected to the recycling place, and open the drain valve. When the residual liquid in the vertical filter flows out through the drain valve, close the drain valve.
5. Open the four sets of eyebolts on the top cover, lift the upper cover, and place the upper cover stably. (the multi bag filter needs to turn a certain angle)
6. Open the snap ring to fix the filter bag and lift out the blocked filter bag. (whether it is necessary to clean and replace the metal inner net)
7. Gently put the metal inner net back into the vertical filter, so that the inner net neckline is consistent with the vertical filter mouth.
8. Place the filter bag so that the ring mouth of the filter bag is in line with the neckline of the metal inner net. (for non top in filter or multi bag filter, buckle the bag pressure ring)
9. Put the O-ring into the O-ring groove, and the O-ring shall not be twisted or deformed.
10. Hold the upper cover handle with one hand and the other end of the upper cover with the other hand. After the upper cover is aligned, tighten the two diagonal lifting caps at the same time, and tighten all lifting caps one by one (insert the short stick into the lifting ring and tighten it).
11. Close vent valve mounted on top of vertical filter.
12. Check whether the connecting pipes are firm and whether the working pressure is within the allowable range.
13. Open the output valve.
14. Slowly open the input valve, let the liquid flow into and fill the filter slowly, to prevent the liquid from suddenly impacting the filter bag, causing the rupture, and then observe whether there is leakage. If there is no leakage, the filtration can be started.
Maintenance of vertical filter:
1. seal ring
When using, the O-ring should be placed in alignment with the o-groove to avoid deformation of the O-ring caused by improper extrusion. When it is not filtered, the Ο type sealing ring must be taken out and wiped clean, otherwise the residual liquid will adhere to its surface after solidification, resulting in hardening and poor sealing.
Replacement: if the O-ring is aged or damaged, please replace it in time. When replacing, choose the same type of O-ring.
2. filter bag
When the liquid input pressure is stable, the filtering quality is closely related to the pressure difference in the filter bag. If the pressure difference is too large, it means that the filtering aperture of the filter bag is blocked and the filtering speed is reduced. Therefore, the pressure difference should be checked regularly, and the time to replace the filter bag should be determined by the pressure difference displayed on the front and rear pressure gauges. Generally, the filter bag can bear a pressure of about 0.5-1kg/cm2 (0.05-0.1mpa). When the pressure difference reaches this range, the filter bag should be replaced in time, so as to avoid the breakage of the filter bag and the damage of the metal inner network caused by the pressure difference.
matters needing attention:
1. If the differential pressure drops suddenly, stop filtering immediately and check whether there is leakage.
2. The filter bag is made of fine fibers, and the hydrophilicity of these materials is weak. The surface of the fiber will not be wetted by water, so like other filter elements made of the same material, it should be wetted with other liquid with lower surface tension before use. Before installation, make sure to immerse the filter bag in the pre wetting liquid matching the filtering liquid for several minutes.
3. Do not open the cover when there is pressure in the vertical filter, or the remaining liquid may spray out, causing liquid loss and personal injury.
The new vertical filter used by our company is compared with the old vertical filter:
Our current vertical filter is upgraded. The color is matte. (see Figure 1, left) although the appearance of the new vertical filter is not as bright as the old one, the new one has the following advantages on the basis of retaining the old one:
1. Compared with the old vertical filter, the new vertical filter has stronger pressure bearing capacity.
2. Compared with the old vertical filter, the new vertical filter has thicker wall thickness and better workmanship. (see Figure 2)
Physical picture of filter bag: