A bag dust collector back-blowing dust cleaning device

Abstract

The present invention relates to a back-blowing and dust-cleaning device for a bag-type dust collector, comprising a box body, the lower part of which is an air inlet duct, and the upper part of which is an air outlet duct; two bins are symmetrically arranged on both sides of the box body, filter bags are arranged in the bins, and the filter bags divide the bin body into an upper chamber and a lower chamber of the bin body; a blowing assembly is arranged on the upper chamber of the bin body; a valve cover suitable for opening and closing the air outlet duct is arranged on the upper chamber of the bin body, and the valve cover is controlled to rise and fall by an offline valve; an auxiliary blowing valve is arranged in the upper chamber of the bin body, and the auxiliary blowing valve is suitable for blowing gas into the upper chamber of the bin body; the inverted installation of the offline valve improves the working reliability of the offline valve, and the compressed gas acts on the rodless cavity of the offline valve cylinder most of the time, thereby reducing the gas source consumption; the use of the auxiliary blowing valve ensures that the inner and outer surfaces of the filter bag are positive pressure differential, thereby improving the blowing effect, and the control cylinder of the auxiliary blowing valve is connected in parallel with the control cylinder of the offline valve, thereby eliminating the additional investment in electrical control and enhancing the back-blowing and dust-cleaning effect of the device.

Description

Technical Field

[0001] The invention relates to the technical field of gas dust removal, and in particular to a back-blowing dust cleaning device for a bag dust collector. Background Art

[0002] The bag dust collector is widely used in industrial enterprises, and is commonly used for environmental dust removal and dust material collection devices. Commonly used medium and large bag dust collectors include multiple independent dust removal bins. When it is necessary to back-blow away the dust adsorbed on the outer surface of the filter bag and collect it in the ash hopper at the bottom of the bin, the usual structure is to cut off the flow of the bin airflow through an offline valve to eliminate the negative pressure difference between the inner and outer surfaces of the filter bag, thereby improving the blowing effect of the back-blow airflow.

[0003] Figure 1 It is a common basic structure of bag dust collector. The lower middle part of the dust collector box is the air inlet duct, the upper part is the air outlet duct, and there are several groups of symmetrical dust removal bins on both sides of the box; the bin is divided into an upper chamber and a lower chamber by multiple groups of cylindrical filter bags; the dust-laden airflow flows from the air inlet duct through the bin air duct into the lower chamber of the bin, and a manual flow regulating valve is set at the inlet of the bin air duct. The dust-laden airflow in the lower chamber of the bin flows from the outer surface of the filter bag to the inner surface, and the dust is adsorbed on the outer surface of the filter bag. The filtered airflow flows through the upper chamber of the bin and the valve port of the offline valve to the air outlet duct, and then is led to the chimney through the dust removal fan and discharged into the atmosphere.

[0004] When the back-blowing cleaning device is working, first close the offline valve to cut off the airflow in the silo. Theoretically, the pressure difference between the inner and outer surfaces of the filter bag in the silo will drop to zero. At this time, a part of the dust adsorbed on the filter bag falls naturally due to gravity, and the dust that has not been detached is further detached from the outer surface of the filter bag under the intermittent vibration of the reverse-blowing compressed air of the injection component, and is deposited in the ash hopper at the bottom of the silo, thus completing a cleaning operation.

[0005] from Figure 1 It can be seen from the observation that because the offline valve is a movable cover plate structure, the valve cover and the valve port are in hard contact with steel materials and are not designed to be tightly sealed. Therefore, when the offline valve is closed, there is inevitably some leakage of air flow, that is, there is still a certain negative pressure difference between the inner and outer surfaces of the filter bag; the airflow of the filter bag caused by this negative pressure difference is opposite to the direction of the injection airflow, thereby weakening the injection cleaning effect.

[0006] On the other hand, for easy installation, the offline valve is usually of a positive structure, that is, when the rod chamber of the offline valve cylinder receives air, the valve cover of the offline valve is lifted up and the valve is opened; when the rodless chamber receives air, the valve cover drops and the valve is closed. In normal operation of the dust collector, the offline valve is in an open state most of the time, so the compressed air acts on the rod chamber of the cylinder most of the time. Because the rod chamber has two leakage channels in the seal, it consumes more compressed air than the rodless chamber; and when the cylinder rod is not sealed tightly, the offline valve will be unable to lift from closed to open due to the pressure difference of the airflow acting on the valve cover, and the valve cannot be opened normally, resulting in the inability of the bin body to enter the dust filtering state.

[0007] Furthermore, as environmental protection indicators become increasingly stringent, the density level of filter bags has been raised. After replacing new filter bags, the overall operating resistance of existing dust collectors has increased significantly. Therefore, higher requirements are placed on the efficiency of the backwash cleaning device to ensure that the overall dust removal air volume does not drop significantly.

[0008] In summary, how to enhance the backwash cleaning effect of the device has become an urgent problem that our researchers need to solve. Summary of the invention

[0009] The technical problem to be solved by the present invention is: how to enhance the back-blowing cleaning effect of the device;

[0010] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0011] The present invention is a back-blowing dust cleaning device for a bag dust collector, comprising a box body, the lower part of the box body is an air inlet duct, and the upper part is an air outlet duct; two bins are symmetrically arranged on both sides of the box body, filter bags are arranged in the bins, and the filter bags divide the bin body into an upper bin chamber and a lower bin chamber; a spray assembly for blowing air to the filter bags is arranged on the upper bin chamber; a valve cover suitable for opening and closing the air outlet duct is arranged on the upper bin chamber, and the valve cover is controlled to rise and fall by an offline valve; an auxiliary blowing valve is arranged in the upper bin chamber, and the auxiliary blowing valve is suitable for blowing gas into the upper bin chamber;

[0012] When in the gas filtering state, the offline valve drives the valve cover to open the air outlet duct, and the filter bag is installed between the upper chamber and the lower chamber of the bin body. The dust-laden air flows through the air inlet duct-the lower chamber of the bin body-the filter bag-the upper chamber of the bin body-the air outlet duct, and the dust is isolated and adsorbed on the outer surface of the filter bag.

[0013] When the filter bag is in dust state, the offline valve drives the valve cover to close the air outlet duct, and supplies external airflow to the upper chamber of the bin through the auxiliary blowing valve, establishing a positive pressure difference between the inner and outer surfaces of the filter bag, opening the spray assembly, blowing gas into the inner surface of the filter bag, and blowing the dust in the filter bag to the bottom of the bin.

[0014] In order to solve the problem of rod seal leakage caused by the constant air supply state of the rod chamber in the conventional design, the present invention adopts an off-line valve including two cylinders fixed on the top of the warehouse body, the output ends of the two cylinders are fixed to the rod connecting plate, a movable connecting sleeve is movably arranged in the middle of the rod connecting plate, a valve stem is fixed at the bottom of the movable connecting sleeve, and a valve cover is arranged at the bottom of the valve stem;

[0015] Conventional offline valves use the output end to move downward, driving the valve cover to close the outlet air duct; the existing method uses an inverted cylinder, that is, the output end moves upward, driving the valve cover to close the outlet air duct, and now compressed gas is used to act on the rodless cavity for a long time, reducing the consumption of compressed gas.

[0016] In order to ensure that the valve cover can be closed with the air outlet duct and prevent it from being deformed and damaged by external forces, the present invention adopts a movable connection sleeve including a rod portion and a sleeve portion connected up and down; a central hole for the rod portion to pass through is opened in the middle of the rod connection plate, the inner diameter of the central hole is larger than the outer diameter of the rod portion, and the length of the rod portion is larger than the thickness of the rod connection plate, and the rod portion passes through the central hole and is connected to the locking nut; the sleeve rod is fixedly connected to one end of the valve stem;

[0017] That is to say, the movable connecting sleeve is movably arranged on the rod connecting plate, and the movable connecting sleeve can move up and down relative to the rod connecting plate. When the output end of the cylinder is in the lowest position, the valve cover falls on the air outlet duct by its own gravity. Traditionally, the movable connecting sleeve and the rod connecting plate are fixedly arranged, and the cylinder drives the valve cover to be against the air outlet duct. The valve cover may be deformed and broken by excessive force. This arrangement ensures that the valve cover can be fully closed in place and prevents it from being deformed and damaged by external force, thereby improving the reliability of back-blowing cleaning of the dust collector.

[0018] Beneficial effects of the invention: The invention is a back-blowing cleaning device for a bag dust collector. The inverted installation of the offline valve improves the working reliability of the offline valve, and the compressed air acts on the rodless chamber of the offline valve cylinder most of the time, reducing the gas source consumption; the use of the auxiliary blowing valve ensures a positive pressure difference between the inner and outer surfaces of the filter bag, thereby improving the blowing effect. When the back-blowing cleaning device operates in the pressure difference mode, more blowing compressed air will be saved; the control cylinder of the auxiliary blowing valve is connected in parallel with the control cylinder of the offline valve, eliminating the additional investment in electrical control, which is beneficial to the low-investment transformation of existing dust removal equipment and enhances the back-blowing cleaning effect of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0020] Figure 1 It is a schematic diagram of the structure of a traditional dust collector;

[0021] Figure 2 It is a schematic diagram of the structure of the present invention;

[0022] Figure 3It is a basic structural diagram of the off-line valve actuator;

[0023] Figure 4 It is a schematic diagram of the discrete components of the off-line valve actuator;

[0024] Figure 5 It is a schematic diagram of the structure and installation of the movable connecting sleeve.

[0025] In the figure: 1. Inlet air duct, 2. Outlet air duct, 3. Off-line valve, 4. Blowing assembly, 5. Upper chamber of the bin, 6. Lower chamber of the bin, 7. Filter bag, 8. Bin air duct, 9. Manual flow control valve, 21. Off-line valve, 24. Blowing valve, 25. Valve cover, 301. Support foot A, 302. Support foot B, 303. Lower bottom plate, 305. Cylinder, 306. Long screw of cylinder, 307. Upper connecting plate, 308. Rod connecting plate, 309. Movable Connecting sleeve, 310. Valve stem, 401. Locking nut, 402. Center hole of rod connecting plate, 403. Cylinder rod through hole of rod connecting plate, 404. Self-aligning guide ring upper pressure plate, 405. Rubber self-aligning guide ring, 406. Self-aligning guide ring lower pressure plate, 407. Screw through hole of upper connecting plate, 408. Cylinder rod through hole of upper connecting plate, 409. Valve stem through hole of lower bottom plate, 410. Long screw threaded hole of lower bottom plate, 501. Rod part, 502. Sleeve part. DETAILED DESCRIPTION

[0026] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0027] like Figure 2 The back-blowing dust cleaning device of a bag filter shown in the figure mainly comprises an upper chamber 5 of the bin body, a lower chamber 6 of the bin body, a blowing assembly 4, a filter bag 7, an offline valve 21, and an auxiliary blowing valve 24. Among them, a plurality of groups of filter bags 7 separate the bin body into an upper chamber 5 of the bin body and a lower chamber 6 of the bin body; the nozzle of the blowing assembly 4 is arranged at the opening of the cylindrical filter bag 7, and the compressed air is sprayed to the inner surface of the filter bag 7 regularly; the offline valve 21 can make the bin body in a dust filtering state, and the other offline valve 21 can make the bin body in a dust removal initial state; the auxiliary blowing valve 24 can supply additional airflow to the upper chamber 5 of the bin body, and the other auxiliary blowing valve 24 cuts off the additional airflow from entering the upper chamber 5 of the bin body.

[0028] During normal dust removal, all the offline valves of the silo are in the open state, and the spraying assembly 4 does not work. During the operation in the time mode or the pressure difference mode, a silo will enter the back-blowing dust removal state in sequence. The silo first closes the offline valve 21 to cut off the dust removal airflow of the silo, weaken and eliminate the negative pressure difference between the inner and outer surfaces of the filter bag 7 of the silo, and prepare for the back-blowing dust removal of the filter bag 7 of the silo. In order to further improve the back-blowing efficiency, when the offline valve of the silo is closed, the blow-assist valve 24 of the cylinder 305 gas port is opened. In addition to offsetting the leakage of the valve cover 25 of the offline valve 21, the additional airflow supplied by the blow-assist valve 24 to the silo flows from the inner surface of the filter bag 7 of the silo to the outer surface, and a positive pressure difference appears on the inner and outer surfaces of the filter bag 7, which improves the back-blowing effect during spraying.

[0029] After the offline valve is closed, the spray assembly 4 of the bin will start to spray in sequence. Because the inner and outer surfaces of all the filter bags 7 of the bin are under positive pressure difference, it is not only conducive to the back-blowing effect of the spray gas, but also in the gaps between the multiple groups of spray valves, the floating dust beaten out will not be adsorbed to the outer surface of other filter bags 7 that are not in the back-blowing state. The overall airflow in the bin moves downward, and the dust fall is accelerated, further improving the dust removal effect.

[0030] like Figure 3-5 As shown, in order to solve the possible deviation of the force caused by the cylinder rod and the valve cover rod of the inverted cylinder being not on the same center line, this embodiment provides an offline valve 21. The actuator is pre-processed and assembled by the manufacturer and shipped as a complete machine to ensure assembly accuracy. On-site installation only requires centering with the valve stem 310 and calibration of the verticality of the cylinder body, and the construction is simple and easy.

[0031] Specifically, the offline valve 21 includes two support legs A301 and B302 made of channel steel to facilitate welding and fixing during on-site installation. The two support legs are connected to the actuator lower base plate 303 through four bolts. The lower base plate valve stem 310 is set in the center of the lower base plate 303 to pass through the lower base plate valve stem through hole 409, and 8 lower base plate long screw threaded holes 410 are symmetrically arranged on both sides. Two cylinders 305 are arranged in the upper part of the lower base plate 303, with the cylinder rods facing upward, and the upper connecting plate 307 is arranged on the upper part of the two cylinders. The rubber self-aligning guide ring 405 is installed in the center opening of the upper connecting plate 307, and is fixed by the self-aligning guide ring upper pressure plate 404 and the self-aligning guide ring lower pressure plate 406. The upper connecting plate screw rod through holes 407 and the upper connecting plate cylinder rod through holes 408 are symmetrically arranged on both sides of the upper connecting plate 307. Thereafter, the lower base plate 303, the two cylinders 305 and the upper connecting plate 307 are connected to form a whole through 8 cylinder long screw rods 306.

[0032] Specifically, the ends of the two cylinder rods contain external threads, and a rod connecting plate 308 is installed on the ends of the two cylinder rods with nuts, and is leveled and locked. The rod connecting plate 308 is provided with a rod connecting plate center hole 402 for connecting the movable connecting sleeve 309, and the rod connecting plate cylinder rod through holes 403 are symmetrically arranged on both sides of the rod connecting plate 308 for connecting the cylinder rods. The movable connecting sleeve 309 is a special-shaped component, including a rod portion 501 with an external thread at the end and a sleeve portion 502 with an internal thread. The rod portion of the movable connecting sleeve 309 passes through the rod connecting plate center hole 402, and the ends are fastened with two locking nuts 401. The rod portion 501 has a vertical momentum of about 2 cm in the rod connecting plate center hole 402. The sleeve portion 502 has an internal thread depth of about 6 cm, which is used to connect the end external thread of the valve cover valve stem 310. After the insertion depth is adjusted, it is locked with a nut.

[0033] Specifically, by adjusting the welding height of the supporting feet of the offline valve 21 and the screwing depth of the movable connecting sleeve 309 and the valve stem 310, the valve cover 25 will be basically in the closed state when the actuator is in the closed position. The best adjustment state is that when the cylinder 305 rod is in the lowest position, the valve cover 25 falls on the upper air outlet duct 2 by its own gravity, and there is a gap of about 1 cm between the rod 501 connected to the valve stem 310 and the rod connecting plate 308. In an abnormal state, when the rod 501 is subjected to force upward, the valve cover 25 may not be fully closed, and when the rod 501 is subjected to force downward, the valve cover 25 may be overstressed, deformed and broken. Therefore, the correct application of the movable connecting sleeve 309 ensures that the valve cover can be fully closed and prevents it from being deformed and damaged by external forces, thereby improving the reliability of the dust collector's back-blowing cleaning.

[0034] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A bag filter back-blowing cleaning device, characterized in that: It comprises a box body, the lower part of which is an air inlet duct (1), and the upper part of which is an air outlet duct (2); The box body is symmetrically provided with bins on both sides, the bins are provided with filter bags (7), and the filter bags divide the bin into an upper bin chamber (5) and a lower bin chamber (6); The upper chamber (5) of the bin body is provided with a blowing assembly for blowing air toward the filter bag; A valve cover for opening and closing the air outlet duct (2) is provided on the upper chamber of the warehouse body, and the lifting and lowering of the valve cover is controlled by an offline valve (21); An auxiliary blowing valve (24) is provided in the upper chamber of the warehouse body, and the auxiliary blowing valve (24) is used to blow gas into the upper chamber (5) of the warehouse body; The offline valve (21) includes two cylinders (305) fixedly mounted on the top of the bin body, and also includes a support foot made of channel steel, the support foot is connected to the lower base plate (303) of the cylinder actuator through bolts, the center of the lower base plate (303) is provided with a lower base plate valve stem through hole (409), the upper part of the lower base plate (303) is provided with two cylinders (305), the cylinder rods are upward, an upper connecting plate (307) is provided on the upper part of the two cylinders, a rubber self-aligning guide ring (405) is installed in the center opening of the upper connecting plate (307), upper connecting plate screw through holes (407) and upper connecting plate cylinder rod through holes (408) are symmetrically arranged on both sides of the upper connecting plate (307), and the lower base plate (303), the cylinder (305), and the upper connecting plate (307) are connected to form a whole through a long cylinder screw (306); The end of the cylinder rod has an external thread, and a rod connecting plate (308) is installed on the end of the cylinder rod with a nut and is leveled and locked. A rod connecting plate center hole (402) is provided on the rod connecting plate (308) for connecting a movable connecting sleeve (309). Rod connecting plate cylinder rod through holes (403) are symmetrically arranged on both sides of the rod connecting plate (308) for connecting the cylinder rod. The movable connecting sleeve (309) includes a rod portion (501) with an external thread at the end and a sleeve portion (502) with an internal thread. The rod of the movable connecting sleeve (309) passes through the center hole (402) of the rod connecting plate and is fastened at the end with two locking nuts (401). The inner diameter of the center hole (402) of the rod connecting plate is larger than the outer diameter of the rod (501). The rod (501) has an up and down movement of about 2 cm in the center hole (402) of the rod connecting plate. The inner thread of the sleeve (502) is about 6 cm deep and is used to connect to the outer thread of the end of the valve stem (310). The bottom of the valve stem (310) is connected to the valve cover. By adjusting the screwing depth of the movable connecting sleeve (309) and the valve stem (310), when the cylinder rod is at the lowest position, the valve cover (25) falls on the air outlet duct by its own gravity.

Images