CN113932238A

CN113932238A - High-efficient exhaust flue of vapour electricity double-drive draught fan

Info

Publication number: CN113932238A
Application number: CN202111028417.5A
Authority: CN
Inventors: 颜刚; 时标; 梁学东; 张允洲; 崔玉岭; 葛宗琴
Original assignee: Huaneng Nanjing Jinling Power Generation Co Ltd
Current assignee: Huaneng Nanjing Jinling Power Generation Co Ltd
Priority date: 2021-09-02
Filing date: 2021-09-02
Publication date: 2022-01-14

Abstract

The invention discloses a high-efficiency exhaust flue of a steam-electricity double-drive induced draft fan, which relates to the field of exhaust flues and comprises a flue pipe, a cleaning device, a scraping device, an extruding device, a flushing device and a pollution discharge device; the fan blades are driven to rotate by blowing through the circulation of smoke, so that the threaded rotary table drives the driving fan blades to slide on the reciprocating screw rod, and the threaded rotary table moves in the reverse direction after moving to one end of the reciprocating screw rod, so that the inner wall of the flue pipe can be comprehensively cleaned, and the cleaning effect of the device is improved; and when the screw thread carousel removed, still can drive the scraper blade and remove to because at connecting rod right side wall fixedly connected with balancing weight, only can take place to slide between consequently connecting rod and the spout, and can not follow screw thread carousel synchronous emergence and rotate, just can sweep the smoke and dust of sweeping down of flue pipe bottom to both ends from this, thereby further improved the clearance effect of the device.

Description

High-efficient exhaust flue of vapour electricity double-drive draught fan

Technical Field

The invention relates to the technical field of exhaust flues, in particular to a high-efficiency exhaust flue of a steam-electricity double-drive induced draft fan.

Background

Gas combustion equipment with a closed hearth, such as a water heater, a boiler or some industrial furnaces and the like, must discharge smoke in time, a smoke discharge channel refers to a channel exhaust channel for discharging smoke generated by a coal-fired stove, and is a tubular device for discharging waste gas and smoke, and the smoke channel sends smoke dust to an external space, and is also called an exhaust channel and a ventilation channel. The traditional induced draft fans of the thermal power plant are all of an electric drive type, but the induced draft fans are large in electric consumption as main auxiliary equipment of a boiler, the power consumption rate of the thermal power plant adopting the electric induced draft fans is high, the economic operation of a unit is not facilitated, and the novel steam-electricity double-drive induced draft fans are adopted, so that the power consumption rate of the thermal power plant can be effectively reduced, the economic efficiency of the unit is improved, and the economic benefit of the thermal power plant is improved; the induced draft fan is used as important auxiliary equipment of a thermal power plant, plays a role in discharging smoke generated in a hearth in the operation process of a thermal power unit, overcomes the effects of pressure loss in a tail flue, hearth negative pressure regulation, stable combustion and the like, and is important regulation equipment of a boiler combustion system of the thermal power unit.

The existing exhaust flue is used for a long time, a large amount of smoke dust, oil stains and the like can be attached to the inside of the flue, the cleaning is difficult, the smoke dust and the oil stains can also obstruct the circulation of the smoke gas, the exhaust efficiency is reduced, and the accumulated smoke dust inside the exhaust flue can not be effectively collected and treated.

Disclosure of Invention

The invention aims to solve the problem that a large amount of smoke dust, oil stain and the like are attached to the interior of the existing exhaust flue and are difficult to clean; a large amount of smoke dust and oil stains can also block the circulation of smoke gas, so that the exhaust efficiency is slowed down; and the accumulated smoke dust inside can not be effectively collected and processed, and the high-efficiency exhaust flue of the steam-electric double-drive induced draft fan is provided.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides a high-efficient exhaust flue of vapour electric double-drive draught fan, includes:

the smoke exhaust device comprises a flue pipe, wherein an induced draft fan for extracting smoke in the flue pipe is installed at the output end of the flue pipe, and a filter screen is fixedly connected to the left side of the inner cavity of the flue pipe;

the cleaning device is arranged inside the flue pipe, two ends of the cleaning device are fixedly connected with the side wall of the flue pipe, and the cleaning device is used for cleaning the inner wall of the flue pipe;

the scraping device is arranged inside the flue pipe, and one end of the scraping device is connected with the inside of the cleaning device in a sliding manner;

the extruding device is arranged inside the flue pipe and is positioned on the right side of the filter screen;

the flushing device is arranged inside the flue pipe and positioned between the filter screen and the extrusion device, two ends of the flushing device are fixedly connected with the side wall of the flue pipe, and the flushing device is used for flushing the filter screen;

and the blowdown device is arranged on two sides of the bottom of the flue pipe and used for removing the garbage cleaned in the flue pipe.

Preferably, cleaning device includes axostylus axostyle, reciprocal lead screw, thread turn table, drive flabellum, clearance piece and spacing ring, axostylus axostyle fixed connection in flue pipe inner chamber lateral wall, axostylus axostyle middle part fixedly connected with reciprocal lead screw, reciprocal lead screw outside threaded connection has the thread turn table, thread turn table lateral wall fixedly connected with the clearance piece, just the clearance piece with the laminating of flue pipe inner wall, the equal fixedly connected with in reciprocal lead screw both ends the spacing ring.

Preferably, scrape and get the device and include connecting rod, balancing weight and scraper blade, connecting rod right side wall fixedly connected with the balancing weight, connecting rod bottom fixedly connected with the scraper blade, the scraper blade with the intraductal laminating of flue, the spout has been seted up to screw thread carousel right side wall, connecting rod and spout inner chamber sliding connection.

Preferably, extrusion device includes the movable rod, goes up the spout, spout and first wedge down, the axostylus axostyle lateral wall has been seted up lower spout, the lateral wall has been seted up on the flue pipe go up the spout, down the spout with sliding connection has between the last spout the movable rod, the right side wall fixedly connected with of movable rod first wedge, just the movable rod lower extreme runs through spout down, the movable rod lower extreme can with conflict between the balancing weight.

Preferably, a fixed plate is installed on the upper portion of one side, close to the movable rod, of the shaft lever, a first spring is fixedly connected to one side, close to the movable rod, of the fixed plate, and the other end of the first spring is fixedly connected with the movable rod.

Preferably, washing unit includes flushing pipe, extrusion groove, piston, second wedge, second spring and shower nozzle, flushing pipe fixed connection with flue pipe inner chamber, seted up at the flushing pipe middle part the extrusion groove, the equal sliding connection in flushing pipe inner chamber both sides has the piston, the piston is close to one side fixedly connected with in extrusion groove the second wedge, two the second wedge can with first wedge is contradicted, two fixedly connected with between the second wedge the second spring, the flushing pipe is close to one side of filter screen is provided with the shower nozzle, just the inside check valve that is provided with of shower nozzle.

Preferably, the left side of the top of the flue pipe is positioned above the flushing pipe and is fixedly connected with a water tank, the two sides of the water tank are both fixedly connected with a guide pipe, and the water tank is communicated with the flushing pipe through the guide pipe.

Preferably, the blowdown apparatus includes blow off pipe and blowoff valve, blow off pipe fixed connection in flue pipe bottom both sides, just the blow off pipe with flue pipe inner chamber intercommunication, the blow off pipe lateral wall is provided with the blowoff valve.

Compared with the prior art, the invention has the beneficial effects that:

1. according to the invention, negative pressure is generated in the flue pipe by the operation of the induced draft fan, the fan blades are driven to rotate by the blowing of the smoke, so that the thread turntable and the reciprocating screw rod rotate, the thread turntable drives the driving fan blades to slide on the reciprocating screw rod, and the thread turntable moves in the reverse direction after moving to one end of the reciprocating screw rod, so that the inner wall of the flue pipe can be comprehensively cleaned, and the cleaning effect of the device is improved; and when the screw thread carousel removed, still can drive the scraper blade and remove to because at connecting rod right side wall fixedly connected with balancing weight, only can take place to slide between consequently connecting rod and the spout, and can not follow screw thread carousel synchronous emergence and rotate, just can sweep the smoke and dust of sweeping down of flue pipe bottom to both ends from this, thereby further improved the clearance effect of the device.

2. The invention synchronously drives the connecting rod to move through the movement of the threaded turntable, so that the balance weight block arranged on the connecting rod is abutted with the movable rod, the movable rod moves towards the left side, then the first wedge block is abutted with the two second wedge blocks, the two second wedge blocks slide towards the two ends of the flushing pipe, so that the piston synchronously slides along the first wedge block, and the water flow in the flushing pipe is sprayed out from the spray head, thereby realizing the flushing of the filter screen, avoiding the blockage phenomenon caused by long-time use, and when the second wedge blocks are not abutted, because the check valve is arranged in the spray head, the water flow can not be sprayed outwards, and when the first wedge blocks are reset under the resilience action of the first spring, the two second wedge blocks are reset under the resilience action of the second spring, thereby also enabling the space in the flushing pipe to be restored as before, at the moment, water flow in the water tank is filled into the flushing pipe through the guide pipe, so that the flushing pipe can subsequently flush the filter screen, and the flushing effect of the device is improved.

3. According to the invention, through the arrangement of the drain pipe and the drain valve, when the scraper sweeps the smoke dust at the bottom of the flue pipe towards two ends, the smoke dust falls into the drain pipe, the water flow generated after the filter screen is flushed also flows into the drain pipe, the water flow can well dissolve the swept smoke dust, and when the device stops running, the smoke dust impurities can be removed by opening the drain valve, so that the phenomenon that the normal use of the device is influenced due to excessive accumulation of the smoke dust impurities in the flue pipe is avoided, and the practicability of the device is improved.

Drawings

FIG. 1 is a schematic view of the overall structure of a high-efficiency exhaust flue of a steam-electric double-drive induced draft fan provided by the invention;

FIG. 2 is a schematic view of a main-view semi-section structure of a high-efficiency exhaust flue of a steam-electric double-drive induced draft fan provided by the invention;

FIG. 3 is an enlarged structural schematic view of a cleaning device for a high-efficiency exhaust flue of a steam-electric double-drive induced draft fan, which is provided by the invention;

FIG. 4 is a schematic structural diagram of a high-efficiency exhaust flue of a steam-electric double-drive induced draft fan provided by the invention;

FIG. 5 is a schematic view of the internal structure of an extrusion device amplifying and flushing device of a high-efficiency exhaust flue of a steam-electric double-drive induced draft fan, which is provided by the invention;

fig. 6 is an enlarged structural schematic diagram of an area a in fig. 5 of the high-efficiency exhaust flue of the steam-electric double-drive induced draft fan provided by the invention.

In the figure: 1. a flue pipe; 2. a filter screen; 3. a cleaning device; 31. a shaft lever; 32. a reciprocating screw rod; 33. a threaded turntable; 331. a chute; 34. driving the fan blades; 35. cleaning the block; 36. a limiting ring; 4. a scraping device; 41. a connecting rod; 42. a balancing weight; 43. a squeegee; 5. an extrusion device; 51. a movable rod; 52. an upper chute; 53. a lower chute; 54. a first wedge block; 6. a flushing device; 61. a flush tube; 62. extruding a groove; 63. a piston; 64. a second wedge block; 65. a second spring; 66. a spray head; 7. a sewage draining device; 71. a blow-off pipe; 72. a blowoff valve; 8. a fixing plate; 81. a first spring; 9. a water tank; 91. a conduit.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

Referring to fig. 1 and 2, a high-efficient exhaust flue of a steam-electricity double-drive induced draft fan comprises:

the flue pipe 1, the output end of the flue pipe 1 is fitted with the draught fan used for extracting the flue gas in the flue pipe 1, the left side of the pipe 1 cavity of flue is fixedly connected with the filter screen 2;

the cleaning device 3 is arranged inside the flue pipe 1, two ends of the cleaning device 3 are fixedly connected with the side wall of the flue pipe 1, and the cleaning device 3 is used for cleaning the inner wall of the flue pipe 1;

the scraping device 4 is arranged inside the flue pipe 1, and one end of the scraping device 4 is connected with the inside of the cleaning device 3 in a sliding manner;

the extruding device 5 is arranged inside the flue pipe 1 and is positioned on the right side of the filter screen 2;

the flushing device 6 is arranged inside the flue pipe 1 and is positioned between the filter screen 2 and the extrusion device 5, two ends of the flushing device 6 are fixedly connected with the side wall of the flue pipe 1, and the flushing device 6 is used for flushing the filter screen 2;

and the pollution discharge device 7 is arranged on two sides of the bottom of the flue pipe 1, and the pollution discharge device 7 is used for discharging the garbage cleaned in the flue pipe 1.

Through the setting of above-mentioned structure, can realize carrying out effective filtration to the inside flue gas of flue pipe 1, avoid the flue gas that discharges to bring adverse effect for the environment to accord with the environmental protection requirement more.

Referring to fig. 2 and 3, wherein, cleaning device 3 includes axostylus axostyle 31, reciprocal lead screw 32, screw thread carousel 33, driving fan leaf 34, clearance piece 35 and spacing ring 36, axostylus axostyle 31 fixed connection is in 1 inner chamber lateral wall of flue pipe, the reciprocal lead screw 32 of axostylus axostyle 31 middle part fixedly connected with, the outside threaded connection of reciprocal lead screw 32 has screw thread carousel 33, screw thread carousel 33 lateral wall fixedly connected with clearance piece 35, and

clearance piece

35 and 1 inner wall of flue pipe laminate mutually, the equal fixedly connected with spacing ring 36 in reciprocal lead screw 32 both ends.

Through the setting of above-mentioned structure, after the draught fan began to work, flue pipe 1 is inside will produce the negative pressure, make the flue gas get into wherein, and will blow drive flabellum 34 through the circulation of flue gas and rotate, make between screw carousel 33 and the reciprocal lead screw 32 rotate, thereby make screw carousel 33 drive flabellum 34 slide on reciprocal lead screw 32, after screw carousel 33 removed to reciprocal lead screw 32 one end, because the setting of spacing ring 36 and the characteristic of reciprocal lead screw 32 itself, screw carousel 33 will remove to the reversal this moment, and can not change the direction of rotation of drive flabellum 34, thereby can realize the comprehensive clearance to flue pipe 1 inner wall, the cleaning performance of the device is improved.

Referring to fig. 2 and 3, the scraping device 4 includes a connecting rod 41, a counterweight 42 and a scraper 43, the right side wall of the connecting rod 41 is fixedly connected with the counterweight 42, the bottom of the connecting rod 41 is fixedly connected with the scraper 43, the scraper 43 is attached to the inner wall of the flue pipe 1, the right side wall of the threaded turntable 33 is provided with a chute 331, and the connecting rod 41 is slidably connected with the inner cavity of the chute 331.

Through the setting of above-mentioned structure, when screw thread carousel 33 moved, still can drive scraper blade 43 and remove to owing to at connecting rod 41 right side wall fixedly connected with balancing weight 42, only can take place to slide between connecting rod 41 and the spout 331, and can not follow screw thread carousel 33 and rotate in step, just can sweep the smoke and dust of sweeping down of flue pipe 1 bottom to both ends from this, thereby improved the clearance effect of the device.

Referring to fig. 2, 3 and 4, wherein, the extruding device 5 includes a movable rod 51, an upper chute 52, a lower chute 53 and a first wedge 54, a lower chute 53 has been opened on the side wall of the shaft rod 31, an upper chute 52 has been opened on the side wall of the flue pipe 1, a movable rod 51 is slidably connected between the lower chute 53 and the upper chute 52, a first wedge 54 is fixedly connected on the right side wall of the movable rod 51, the lower end of the movable rod 51 penetrates through the lower chute 53, and the lower end of the movable rod 51 can be abutted against the counterweight 42.

Through the setting of above-mentioned structure, when connecting rod 41 follows screw carousel 33 and moves to flue pipe 1 left side, the balancing weight 42 that sets up on connecting rod 41 will contradict between 51 with the movable rod to make movable rod 51 remove to the left side, thereby can ensure first wedge 54 smoothly with carry out the linkage cooperation between washing unit 6.

Referring to fig. 4, a fixed plate 8 is mounted on the upper portion of the shaft 31 near the movable rod 51, a first spring 81 is fixedly connected to the fixed plate 8 near the movable rod 51, and the other end of the first spring 81 is fixedly connected to the movable rod 51.

Through the arrangement of the structure, the movable rod 51 after being collided and moved can be ensured to be smoothly reset, and the normal operation of the whole extrusion device 5 is ensured.

Referring to fig. 4, 5 and 6, wherein the flushing device 6 includes a flushing pipe 61, an extrusion groove 62, a piston 63, a second wedge block 64, a second spring 65 and a nozzle 66, the flushing pipe 61 is fixedly connected with the inner cavity of the flue pipe 1, the extrusion groove 62 is provided in the middle of the flushing pipe 61, the pistons 63 are slidably connected to both sides of the inner cavity of the flushing pipe 61, the second wedge block 64 is fixedly connected to one side of the piston 63 close to the extrusion groove 62, the two second wedge blocks 64 can be abutted against the first wedge block 54, the second spring 65 is fixedly connected between the two second wedge blocks 64, the nozzle 66 is provided on one side of the flushing pipe 61 close to the filter screen 2, and a one-way valve is provided inside the nozzle 66.

Through the setting of above-mentioned structure, follow movable rod 51 when first wedge 54 and remove the back to having, can conflict between two second wedges 64, make two second wedges 64 slide to flushing pipe 61 both ends, thereby make piston 63 follow its synchronous emergence and slide, thereby spray away from the rivers in the flushing pipe 61 from shower nozzle 66, thereby wash filter screen 2, avoid it to lead to the phenomenon of jam because long-time the use, and when second wedge 64 did not contradict, because the inside check valve that is provided with of shower nozzle 66, consequently, the rivers can not outwards spray.

Referring to fig. 2, 2 and 5, a water tank 9 is fixedly connected to the left side of the top of the flue pipe 1 above the flushing pipe 61, a guide pipe 91 is fixedly connected to both sides of the water tank 9, and the water tank 9 is communicated with the flushing pipe 61 through the guide pipe 91.

Through the arrangement of the structure, when the first wedge-shaped block 54 is reset under the rebound action of the first spring 81, the two second wedge-shaped blocks 64 are also reset under the rebound action of the second spring 65, so that the space inside the flushing pipe 61 is recovered as before, but the water flow is reduced under the extrusion action of the first wedge-shaped block 54, at the moment, the water flow in the water tank 9 is filled into the flushing pipe 61 through the guide pipe 91, the water flow inside the flushing pipe 61 is always in a full state, so that the flushing pipe 61 can be ensured to wash the filter screen 2 subsequently, and the flushing effect of the device is improved.

Referring to fig. 1 and 2, wherein the sewage discharging device 7 comprises a sewage discharging pipe 71 and a sewage discharging valve 72, the sewage discharging pipe 71 is fixedly connected to two sides of the bottom of the flue pipe 1, the sewage discharging pipe 71 is communicated with the inner cavity of the flue pipe 1, and the sewage discharging valve 72 is arranged on the side wall of the sewage discharging pipe 71.

Through the setting of above-mentioned structure, after the smoke and dust of scraper blade 43 bottom flue pipe 1 sweeps the both ends, the smoke and dust will fall into blow off pipe 71 inside, and filter screen 2 rivers after washing also can flow into blow off pipe 71 inside, and above-mentioned rivers can also be fine dissolve the smoke and dust that will sweep, after the device stops the operation, can get rid of these smoke and dust impurities through opening blowoff valve 72, avoid flue pipe 1 inside smoke and dust impurity to pile up too much and influence device normal use, thereby the practicality of the device has been improved.

Referring to fig. 1-6, in the invention, after the induced draft fan starts working, negative pressure is generated inside the flue pipe 1, so that flue gas enters the flue pipe, and the flow of the flue gas blows the driving fan blades 34 to rotate, so that the thread turntable 33 and the reciprocating screw rod 32 rotate, and the thread turntable 33 drives the driving fan blades 34 to slide on the reciprocating screw rod 32, after the thread turntable 33 moves to one end of the reciprocating screw rod 32, due to the arrangement of the limiting ring 36 and the characteristics of the reciprocating screw rod 32, the thread turntable 33 moves in the reverse direction at the moment, and the rotating direction of the driving fan blades 34 cannot be changed, so that the inner wall of the flue pipe 1 can be comprehensively cleaned, and the cleaning effect of the device is improved; when the threaded turntable 33 moves, the scraper 43 is driven to move, and the counterweight 42 is fixedly connected to the right side wall of the connecting rod 41, so that the connecting rod 41 and the chute 331 only slide but do not synchronously rotate along with the threaded turntable 33, and the swept smoke at the bottom of the flue pipe 1 can be swept to two ends, thereby further improving the cleaning effect of the device;

when the connecting rod 41 moves to the left side of the flue pipe 1 along with the threaded turntable 33, the weight block 42 arranged on the connecting rod 41 will collide with the movable rod 51, so that the movable rod 51 moves to the left side, and then the first wedge-shaped block 54 will collide with the two second wedge-shaped blocks 64, so that the two second wedge-shaped blocks 64 will slide towards the two ends of the flushing pipe 61, so that the piston 63 will slide synchronously along with the piston, so as to spray the water flow in the flushing pipe 61 out of the spray head 66, so as to flush the filter screen 2, and avoid the blockage caused by long-term use, and when the second wedge-shaped block 64 is not collided, because the inside of the spray head 66 is provided with a one-way valve, the water flow will not spray outwards, and when the first wedge-shaped block 54 is reset under the resilience of the first spring 81, the two second wedge-shaped blocks 64 will also reset under the resilience of the second spring 65, therefore, the space inside the flushing pipe 61 is recovered as before, but the water flow is reduced under the extrusion action of the first wedge-shaped block 54, at this time, the water flow in the water tank 9 is filled into the flushing pipe 61 through the guide pipe 91, so that the water flow inside the flushing pipe 61 is always in a full state, the flushing pipe 61 can be ensured to flush the filter screen 2 subsequently, and the flushing effect of the device is improved;

then sweep the smoke and dust of flue pipe 1 bottom to both ends through scraper blade 43, the smoke and dust will fall into blow off pipe 71 inside this moment, and filter screen 2 rivers after washing also can flow into blow off pipe 71 inside, and above-mentioned rivers can also be fine dissolve the smoke and dust of sweeping down, after the device stops the operation, can get rid of these smoke and dust impurities through opening blowoff valve 72, avoid flue pipe 1 inside smoke and dust impurity to pile up too much and influence the device normal use, thereby the practicality of the device has been improved.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims

1. The utility model provides a high-efficient exhaust flue of vapour electricity double-drive draught fan which characterized in that includes:

the flue pipe (1), the output end of the flue pipe (1) is provided with a draught fan for extracting flue gas in the flue pipe (1), and the left side of the inner cavity of the flue pipe (1) is fixedly connected with a filter screen (2);

the cleaning device (3) is arranged inside the flue pipe (1), two ends of the cleaning device (3) are fixedly connected with the side wall of the flue pipe (1), and the cleaning device (3) is used for cleaning the inner wall of the flue pipe (1);

the scraping device (4) is arranged inside the flue pipe (1), and one end of the scraping device (4) is connected with the inside of the cleaning device (3) in a sliding manner;

the extruding device (5) is arranged inside the flue pipe (1) and is positioned on the right side of the filter screen (2);

the flushing device (6) is arranged inside the flue pipe (1) and is positioned between the filter screen (2) and the extrusion device (5), two ends of the flushing device (6) are fixedly connected with the side wall of the flue pipe (1), and the flushing device (6) is used for flushing the filter screen (2);

blowdown apparatus (7), blowdown apparatus (7) set up in flue pipe (1) bottom both sides, blowdown apparatus (7) are used for getting rid of the inside rubbish that cleans of flue pipe (1).

2. The high-efficiency exhaust flue of the steam-electric double-drive induced draft fan according to claim 1, wherein the cleaning device (3) comprises a shaft rod (31), a reciprocating screw rod (32), a threaded turntable (33), driving fan blades (34), a cleaning block (35) and a limiting ring (36), the shaft rod (31) is fixedly connected to the side wall of the inner cavity of the flue pipe (1), the reciprocating screw rod (32) is fixedly connected to the middle of the shaft rod (31), the threaded turntable (33) is in threaded connection with the outer side of the reciprocating screw rod (32), the cleaning block (35) is fixedly connected to the outer side wall of the threaded turntable (33), the cleaning block (35) is attached to the inner wall of the flue pipe (1), and the limiting ring (36) is fixedly connected to two ends of the reciprocating screw rod (32).

3. The high-efficiency exhaust flue of the steam-electric double-drive induced draft fan as claimed in claim 2, wherein the scraping device (4) comprises a connecting rod (41), a balancing weight (42) and a scraping plate (43), the right side wall of the connecting rod (41) is fixedly connected with the balancing weight (42), the bottom of the connecting rod (41) is fixedly connected with the scraping plate (43), the scraping plate (43) is attached to the inner wall of the flue pipe (1), the right side wall of the threaded turntable (33) is provided with a sliding groove (331), and the connecting rod (41) is slidably connected with the inner cavity of the sliding groove (331).

4. The high-efficiency exhaust flue of the steam-electric double-drive induced draft fan according to claim 2, wherein the extrusion device (5) comprises a movable rod (51), an upper chute (52), a lower chute (53) and a first wedge-shaped block (54), the lower chute (53) is formed in the side wall of the shaft rod (31), the upper chute (52) is formed in the side wall of the flue pipe (1), the movable rod (51) is connected between the lower chute (53) and the upper chute (52) in a sliding manner, the first wedge-shaped block (54) is fixedly connected to the right side wall of the movable rod (51), the lower end of the movable rod (51) penetrates through the lower chute (53), and the lower end of the movable rod (51) can be abutted against the counter weight block (42).

5. The high-efficiency exhaust flue of the steam-electric double-drive induced draft fan according to claim 4, wherein a fixing plate (8) is installed on the upper portion of one side, close to the movable rod (51), of the shaft lever (31), a first spring (81) is fixedly connected to one side, close to the movable rod (51), of the fixing plate (8), and the other end of the first spring (81) is fixedly connected with the movable rod (51).

6. The high-efficiency exhaust flue of the induced draft fan driven by both steam and electricity as claimed in claim 5, wherein the flushing device (6) comprises a flushing pipe (61), an extrusion groove (62), a piston (63), second wedge blocks (64), a second spring (65) and a spray head (66), the flushing pipe (61) is fixedly connected with the inner cavity of the flue pipe (1), the extrusion groove (62) is formed in the middle of the flushing pipe (61), the piston (63) is slidably connected to both sides of the inner cavity of the flushing pipe (61), the second wedge blocks (64) are fixedly connected to one side of the piston (63) close to the extrusion groove (62), the two second wedge blocks (64) can be abutted against the first wedge block (54), the second spring (65) is fixedly connected between the two second wedge blocks (64), and the spray head (66) is arranged on one side of the flushing pipe (61) close to the filter screen (2), and a one-way valve is arranged inside the spray head (66).

7. The high-efficiency exhaust flue of the steam-electric double-drive induced draft fan according to claim 6, wherein the left side of the top of the flue pipe (1) is positioned above the flushing pipe (61) and is fixedly connected with a water tank (9), both sides of the water tank (9) are fixedly connected with a guide pipe (91), and the water tank (9) is communicated with the flushing pipe (61) through the guide pipe (91).

8. The high-efficiency exhaust flue of the steam-electric double-drive induced draft fan as claimed in claim 1, wherein the blowdown device (7) comprises a blowdown pipe (71) and a blowdown valve (72), the blowdown pipe (71) is fixedly connected to two sides of the bottom of the flue pipe (1), the blowdown pipe (71) is communicated with the inner cavity of the flue pipe (1), and the blowdown valve (72) is arranged on the side wall of the blowdown pipe (71).