Steel ladle bottom pouring fume collection system and fume collection method

Abstract

The present invention proposes a ladle bottom pouring smoke collection system and a smoke collection method, which belong to the field of smoke collection in the foundry industry. The ladle bottom pouring smoke collection system includes a smoke exhaust main pipe, a docking valve, a ladle bottom pouring collection hood, a walking track and a reserved opening sealing device; the ladle bottom pouring collection hood includes a first independent collection hood and a second independent collection hood. During pouring, the two independent ladle bottom pouring collection hoods are docked as a whole and symmetrical along the docking surface. The pouring smoke collection system of the present invention can form a small sealed space at the pouring station by improving the design and sealing method of the dust hood, and cooperating with the switching of the docking valve. The space has good sealing performance and can greatly reduce the air volume required for dust removal compared with the top suction hood, thereby greatly improving the collection efficiency. Compared with the solution of isolating the entire pouring workshop, it is more energy-saving and better operable.

Description

Technical Field

[0001] The invention belongs to the field of smoke collection in the casting industry, and in particular relates to a ladle bottom pouring smoke collection system and a smoke collection method. Background Art

[0002] In the pouring process of large castings in the foundry industry, a crane is required to lift the ladle for pouring. The ladle leaks molten steel into the sand box or mold through the pouring valve at the bottom of the ladle. A large amount of smoke and dust will be generated during the pouring process, mainly splashing dust caused by the falling molten steel, smoke and dust generated by the gasification of the sand box core, and smoke and volatiles generated by the heating of the molding sand. A large amount of smoke and dust leads to a harsh environment at the pouring site, so the smoke and dust need to be collected.

[0003] The existing bottom pouring collection hoods of the pouring ladle are mostly top suction type, side suction type and semi-enclosed mobile type. However, due to the need to move the hanging ladle and operate the bottom gate, the dust hood is far away from the pouring point and cannot effectively collect a large amount of smoke and harmful gases generated during the pouring process, causing environmental pollution in the entire workshop. Chinese invention patent CN110538853A discloses a method for using a movable fully enclosed casting dust removal facility, in which dust hood tracks are set on both sides of the casting sand box, a movable dust hood is set on the track, and electric rolling shutter doors are installed on both sides of the dust hood. The top of the dust hood is connected to the storage bin of a large vacuum cleaner through a wire hose to achieve the closure of the pouring area and improve the smoke collection effect. However, the dust hood uses a wire hose to adjust the position, which is complicated to operate and costly, and it is impossible to avoid the smoke from overflowing through the pouring port during pouring. There are still problems of low smoke efficiency and high air leakage rate. Summary of the invention

[0004] In view of the problems existing in the pouring of the above-mentioned large castings, the present invention proposes a ladle bottom pouring fume collection system and a fume collection method which can effectively seal the dust and fume during the pouring process, have high efficiency in collecting fume and high air volume utilization.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] The ladle bottom pouring smoke and dust collection system comprises a smoke exhaust main pipeline, a docking valve, a ladle bottom pouring collection hood, a walking track, a reserved opening sealing device, and a lighting and monitoring system.

[0007] The bottom casting collection cover includes a first independent collection cover and a second independent collection cover. The top of the first independent collection cover is provided with a smoke exhaust port, a reserved opening for a crane and a reserved opening sealing device, and the bottom is provided with a walking device; the smoke exhaust port is matched with a main pipeline docking valve, and the reserved opening for the crane is a rectangular gap with three sides closed and one side open.

[0008] The reserved opening sealing device includes a sealing baffle, a tensioning spring, a control motor, a sliding groove, a retractable elastic rope, a tarpaulin coating, a rolling rod and an overhead crane inductive positioning device; a sliding groove is arranged above the boundary of the overhead crane reserved opening along the extension direction of the track, the sealing baffle is located above the sliding groove and just covers the overhead crane reserved opening, and the retractable elastic rope is pulled by the control motor to perform telescopic movement, and the tensioning spring is used to assist in tightening the sealing baffle; a tarpaulin coating is also arranged at the overhead crane reserved opening, and the tarpaulin coating is retracted by the rolling rod, and is usually retracted and rolled into a roll. When the sealing baffle moves, it is pulled out with the sealing baffle, and is the same size as the sealing baffle when fully unfolded; the overhead crane inductive positioning device is a row of magnetic overhead crane inductive positioners arranged along one side of the overhead crane reserved opening, which can sense the position of the overhead crane and be interlocked with the control motor to control the telescopic distance of the sealing baffle.

[0009] The second independent collecting hood has the same structure as the first independent collecting hood and can move freely on the walking track. During pouring, the two independent bottom casting collecting hoods are connected as a whole and are symmetrical along the connecting surface. The reserved opening of the overhead traveling crane is in the shape of a rectangular hole.

[0010] Preferably, except for the docking surface and the overhead crane reserved opening, the other three side surfaces and the top surface of the first and second independent collecting hoods are steel structure wall panels, and the height from the bottom of the side structure wall panels to the ground is greater than 2 meters.

[0011] Preferably, a heat-resistant material is laid inside the steel structure wall panel, and the heat-resistant material is an aluminum silicate plate.

[0012] Preferably, a buffer labyrinth sealing structure is provided at the butt joint surface between the first independent collecting hood and the second independent collecting hood.

[0013] Preferably, the buffer labyrinth sealing structure is sealed by a concave-convex structure, and a rubber pad is provided at the concave part.

[0014] Preferably, the bottom cast collecting hood has a consistent height at all locations along the track direction, the cross section perpendicular to the track direction is gradually elevated, and the smoke exhaust port is located at the highest point of the hood body.

[0015] Preferably, the pouring sand box can be arranged in an underground pit, a semi-underground pit or on the ground.

[0016] The present invention also discloses a fume collection method of the ladle bottom pouring fume collection system, comprising the following steps:

[0017] a. Separate the first independent collection hood from the second independent collection hood, lift the ladle by the overhead crane into the pouring area, roughly locate the ladle bottom pouring valve and the sand box riser, and then close the two independent ladle bottom pouring collection hoods;

[0018] b. Adjust the position of the bottom pouring collection hood, connect the exhaust port of the bottom pouring collection hood with the dust suction port of the main pipeline, and turn on the fan;

[0019] c. Start the control motor at the reserved opening of the crane on the top of the ladle bottom pouring collection cover, sense the position of the crane through the crane sensing positioning device, move the sealing baffle to seal the reserved opening of the crane, and now the hanging ladle and the sand box are sealed in the ladle bottom pouring collection cover;

[0020] d. The operator locates the ladle bottom pouring valve and the sand box riser, opens the ladle bottom pouring valve, injects molten steel into the sand box or steel mold, and starts pouring;

[0021] e. After the first sand box pouring is completed, the hanging ladle moves inside the pouring collection cover at the bottom of the ladle along the reserved crane opening of the cover body under the command of the operator. Under the guidance of the crane induction positioning device, the motor is controlled to drive the double-sided sealing baffles to move correspondingly with the movement of the crane. After the ladle is positioned at the next pouring point, the second sand box pouring is carried out;

[0022] f. When all the sand boxes in the ladle bottom pouring collection hood are poured, the smoke in the hood is emptied, the ladle bottom pouring collection hood moves on the walking track, and the smoke exhaust port moves to the next docking valve under the smoke exhaust main pipeline;

[0023] g. After the docking is completed, move the ladle to the predetermined pouring position, open the exhaust main pipe docking valve, and enter the next pouring cycle;

[0024] h. When the molten steel in the ladle is used up, the smoke in the pouring collection hood at the bottom of the ladle is emptied, the first independent collection hood and the second independent collection hood are separated, and the overhead crane is driven to move the ladle away for replacement.

[0025] Preferably, when the sand box needs to be arranged in the pouring pit before pouring, the sand box pouring riser is arranged in a straight line along the direction of the walking track of the bottom pouring and collecting cover, and is arranged in the middle of the reserved overhead crane opening of the bottom pouring and collecting cover.

[0026] Preferably, the movement of the ladle bottom pouring collection cover and the overhead crane ladle must be directed by the operator inside the cover, and they can move simultaneously or separately.

[0027] Compared with the prior art, the advantages and positive effects of the present invention are:

[0028] 1. The pouring fume collection system of the present invention improves the design and sealing method of the dust hood, adopts a fully enclosed collection form, an openable / closed mobile hood combination structure, and is matched with the switching of the docking valve to form a small sealed space at the pouring station with good sealing performance. Compared with the top suction hood, it can greatly reduce the air volume required for dust removal and improve the collection efficiency. Compared with the solution of isolating the entire pouring workshop, it is more energy-saving and more operable.

[0029] 2. The mobile bottom pouring collection hood adopts a gradually rising hood structure to buffer the large amount of smoke and dust discharged at the moment of pouring, and can effectively collect it at the highest point, which is conducive to controlling the entire system with lower air volume.

[0030] 3. By setting the switching valve of the smoke exhaust main pipeline, the bottom pouring collection cover can be applied to each pouring station to save environmental protection dust removal investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A front view of a ladle bottom pouring fume collection system provided by an embodiment of the present invention;

[0032] Figure 2 A top view of a ladle bottom pouring fume collection system provided by an embodiment of the present invention;

[0033] Figure 3 A cross-sectional view of a ladle bottom pouring fume collection system in the form of a pit provided in an embodiment of the present invention in a direction perpendicular to the track;

[0034] Figure 4 Figure 3 A cross-sectional view of a ladle bottom pouring fume collection system in a semi-pit form provided by an embodiment of the present invention in a direction perpendicular to the track;

[0035] Figure 5 Figure 3 A cross-sectional view of a ladle bottom pouring fume collection system in a form where the sand box provided in an embodiment of the present invention is on the ground and in a vertical direction to the track;

[0036] Figure 6 A schematic diagram of a sealing device for a reserved opening of a ladle bottom pouring fume collection system provided in an embodiment of the present invention;

[0037] Figure 7 A schematic diagram of the joint between two ladle bottom pouring collection hoods in the ladle bottom pouring smoke collection system provided by an embodiment of the present invention;

[0038] Figure 8 A working state diagram of the ladle bottom pouring smoke collection system provided by the embodiment of the present invention when collecting smoke;

[0039] In the figure, 11: exhaust main pipe, 12: docking valve, 21: exhaust port, 22: first independent collecting hood, 22': second independent collecting hood, 23: walking device, 24: buffer labyrinth sealing structure, 241: concave-convex structure, 242: rubber pad, 25: reserved opening sealing device, 251: control motor, 252: tarpaulin coating, 253: sealing baffle, 254: tension spring, 255: sliding groove, 256: shrink elastic rope, 257: rolling rod, 26: overhead crane reserved opening, 27: walking track, 31: ladle, 32: ladle bottom pouring valve, 41: sand box, 42: pouring pit. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] like Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a ladle bottom pouring smoke collection system, including a smoke exhaust main pipe 11, a docking valve 12, a ladle bottom pouring collection cover, a walking track 23, a reserved opening sealing device 25 and a lighting and monitoring system.

[0042] The bottom-wrapped pouring and collecting hood includes a first independent collecting hood 22 and a second independent collecting hood 22'. The first independent collecting hood 22 is provided with a smoke exhaust port 21, a crane reserved port 26 and a reserved port sealing device 25 at the top, and a running device 23 at the bottom; the smoke exhaust port 21 cooperates with the main pipeline docking valve 12, and the position can be adjusted according to different pouring points, so that one set of equipment can be used at multiple points. The crane reserved port 26 is a rectangular gap with three sides closed and one side open. This allows the crane to move flexibly and facilitates pouring. The second independent collecting hood 22' has the same structure as the first independent collecting hood 22, and both can move freely on the running track 27; during pouring, the two independent bottom-wrapped pouring and collecting hoods are docked as a whole, and are symmetrical along the docking surface, and the crane reserved port 26 is a rectangular hole.

[0043] Further Figure 3 As shown, the bottom casting collection cover has the same height along the track direction, and the cross section perpendicular to the track direction is gradually raised. The smoke outlet 21 is located at the highest point of the cover body, which makes it easy for smoke to flow to the smoke outlet, improves the smoke exhaust efficiency and avoids smoke overflow. Figure 3-5 As shown in the figure, according to the work needs and the actual situation on site, the casting sand box can have three different layout forms: Figure 3 In the form of a pit. Figure 4 It is a semi-underground pit. Figure 5 It is an above-ground form, and different arrangements will not affect the collection efficiency of the bottom-cast collection hood described in this solution.

[0044] Further Figure 6 As shown, in order to ensure the sealing of the bottom casting collection cover, the reserved opening sealing device 25 includes a control motor 251, a tarpaulin coating 252, a sealing baffle 253, a tensioning spring 254, a sliding groove 255, a shrinking elastic rope 256, a rolling rod 257 and an overhead crane induction positioning device; the overhead crane reserved opening 26 is provided with a sliding groove 255 above the boundary along the extension direction of the track, and the sealing baffle 253 is located above the sliding groove 255 and just covers the overhead crane reserved opening 26. The shrinking elastic rope 256 is pulled by the control motor 251 to perform telescopic movement, and the tensioning spring 254 tightens the bottom fixed point of the sealing plate, and relies on elasticity to approach the overhead crane wire rope, thereby playing a role in assisting in tightening the sealing baffle 253.

[0045] A tarpaulin film 252 is also provided at the reserved opening 26 of the crane. The tarpaulin film 252 is extended and retracted by a rolling rod 257. It is usually retracted and rolled up. When the sealing baffle 253 moves, it is pulled out with the sealing baffle 253. When it is fully unfolded, it is the same size as the sealing baffle 253. The crane induction positioning device is a row of magnetic crane induction positioners provided along one side of the reserved opening 26 of the crane. It can sense the position of the crane and interlock with the control motor 251 to control the extension and retraction distance of the sealing baffle 253. In the above-mentioned reserved opening sealing device, the sealing baffle and the tarpaulin film are matched to adopt a follow-up sealing method, so that the bottom casting collection hood is always in a sealed state after closing, and the sealing performance is good. Compared with the top suction hood, the air volume required for dust removal can be greatly reduced, and the collection efficiency is improved.

[0046] In order to improve the overall strength and stability of the device, the first independent collection cover 22 and the second independent collection cover 22', except for the docking surface and the overhead crane reserved opening 26, the other three sides and the top surface are all steel structure wall panels, and the heat-resistant material is laid inside. The heat-resistant material is an aluminum silicate plate and is set in a stretched mesh form, which can play the role of sound absorption, heat insulation, and splash prevention. It can not only protect the operators in the collection cover, but also prevent the deformation of the collection cover caused by overheating of molten iron. The bottom of the side structure wall panel is more than 2 meters above the ground, which does not block the operator's line of sight, has a large moving space, has no effect on command and operation, and is easier for operators to use.

[0047] Further Figure 7As shown, a buffer labyrinth sealing structure 24 is provided at the docking surface of the first independent collecting hood 22 and the second independent collecting hood 22'. The buffer labyrinth sealing structure 24 is sealed by a concave-convex structure 241 to increase the sealing performance of the two bottom-cast collecting hoods after docking. In addition, a rubber pad 242 is provided at the concave part to play a buffering role when the two movable hoods are docked.

[0048] In addition, there is a blind spot in the collection hood for the crane operator. Therefore, in order to facilitate the crane operator to move the crane and avoid unnecessary operations, a monitor is provided in the bottom casting collection hood. The monitor can be located at the four top corners of the collection hood. In order to increase visibility, a lighting device is also provided in the collection hood.

[0049] The present invention also discloses a fume collection method of the ladle bottom pouring fume collection system, comprising the following steps:

[0050] a. Separate the first independent collecting cover 22 from the second independent collecting cover 22', lift the ladle 31 by a crane into the pouring area, roughly position the ladle bottom pouring valve 32 and the riser of the sand box 41, and close the two independent ladle bottom pouring and collecting covers. Figure 8 shown.

[0051] b. Adjust the position of the bottom pouring collection hood, connect the smoke exhaust port 21 of the bottom pouring collection hood with the main pipeline connection valve 12, and start the fan.

[0052] c. Start the control motor 251 at the reserved opening 26 of the crane on the top of the ladle bottom pouring collection cover, sense the position of the crane through the crane sensing positioning device, move the sealing baffle 253 to seal the reserved opening 26 of the crane, and now the hanging ladle and the sand box are sealed in the ladle bottom pouring collection cover.

[0053] d. The operator locates the ladle bottom pouring valve 32 and the riser of the sand box 41, opens the ladle bottom pouring valve 32, injects molten steel into the sand box, and starts pouring; at this time, the ladle bottom pouring collection hood is a closed structure, and the smoke and dust generated are collected by the top collection port. There is no pouring space in the hood, which can buffer the large amount of smoke and harmful gases generated by the gasification of the core in the initial pouring.

[0054] e. After the pouring of the first sand box is completed, the hanging ladle, under the command of the operator, moves inside the pouring collection cover at the bottom of the ladle along the reserved crane opening of the cover body. Under the guidance of the crane induction positioning device, the control motor drives the double-sided sealing baffles to move accordingly with the movement of the crane. After the ladle is positioned at the next pouring point, the second sand box is poured.

[0055] f. When all the sand boxes in the bottom pouring and collecting hood are poured, the smoke in the hood is emptied, the bottom pouring and collecting hood moves on the walking track 27, and the smoke exhaust port 21 moves to a docking valve under the smoke exhaust main pipeline 11.

[0056] g. After the docking is completed, move the ladle to the predetermined pouring position, open the docking valve 12 of the smoke exhaust main pipeline 11, and enter the next pouring cycle.

[0057] h. When the molten steel in the ladle is used up, the smoke in the pouring and collecting hood at the bottom of the ladle is emptied, the first independent collecting hood 22 and the second independent collecting hood 22' are separated, and the overhead crane is driven to move the ladle away for replacement.

[0058] In order to further reduce the positioning time of the overhead crane and shorten the pouring time of molten steel, when the sand box 41 is arranged in the pouring pit 42 before pouring, the sand box pouring riser needs to be arranged in a straight line along the direction of the walking track 27 of the ladle bottom pouring collection cover, and arranged in the middle of the reserved overhead crane opening 26 of the ladle bottom pouring collection cover. It can be understood that the arrangement of the sand box pouring riser does not have to be a straight line, and pouring can also be achieved with a certain lateral distance, because the overhead crane can also move laterally, but the amplitude is smaller, and because the outlet of the bottom ladle is generally eccentric, it can be rotated according to the center of the overhead crane hook to adjust the lateral distance between the bottom pouring opening and the moving direction of the crane. It should be pointed out that the movement of the ladle bottom pouring collection cover and the overhead crane ladle must be commanded by the operator inside the cover and operated in conjunction with the monitor. They can move simultaneously or separately.

[0059] The device of the present invention can flexibly adjust the mold according to different castings, and is not only applicable to sand boxes, but also to other forms of molds.

Claims

1. The ladle bottom pouring fume collection system is characterized by: It includes main smoke exhaust pipe, docking valve, bottom casting collection cover, walking track, reserved opening sealing device, lighting and monitoring system; The bottom casting collection cover comprises a first independent collection cover and a second independent collection cover, wherein the first independent collection cover is provided with a smoke exhaust port, a reserved opening for a crane and a reserved opening sealing device at the top, and a walking device at the bottom; the smoke exhaust port is matched with a main pipeline butt valve, and the reserved opening for the crane is a rectangular gap with three sides closed and one side open; The reserved opening sealing device comprises a sealing baffle, a tensioning spring, a control motor, a sliding groove, a retractable elastic rope, a tarpaulin coating, a rolling rod and an overhead travelling crane inductive positioning device; a sliding groove is arranged above the boundary of the overhead travelling crane reserved opening along the extension direction of the track, the sealing baffle is located above the sliding groove and just covers the overhead travelling crane reserved opening, and the retractable elastic rope is pulled by the control motor to perform telescopic movement, and the tensioning spring is used to assist in tightening the sealing baffle; a tarpaulin coating is also arranged at the overhead travelling crane reserved opening, and the tarpaulin coating is retracted and stretched by the rolling rod, and is usually retracted and rolled into a roll, and is pulled out with the sealing baffle when the sealing baffle moves, and is the same size as the sealing baffle when fully unfolded; the overhead travelling crane inductive positioning device is a row of magnetic induction overhead travelling crane inductive positioning devices arranged along one side of the overhead travelling crane reserved opening, which can sense the position of the overhead travelling crane and be interlocked with the control motor to control the telescopic distance of the sealing baffle; The second independent collecting hood has the same structure as the first independent collecting hood, and both can move freely on the walking track; during pouring, the two independent bottom pouring collecting hoods are butt-jointed into a whole, and are symmetrical along the butt-joint surface, and the reserved opening of the overhead traveling vehicle is in the shape of a rectangular hole; Except for the butt joint surface and the reserved opening for the overhead crane, the other three sides and the top surface of the first independent collection cover and the second independent collection cover are all steel structure wall panels, and the height of the bottom of the side structure wall panels from the ground is greater than 2 meters; A buffer labyrinth sealing structure is provided at the butt joint surface between the first independent collecting hood and the second independent collecting hood; The bottom-cast collecting hood has a consistent height at all locations along the track direction, and the cross-section perpendicular to the track direction is gradually elevated, and the smoke exhaust port is located at the highest point of the hood body.

2. The ladle bottom pouring fume collection system according to claim 1, characterized in that: The interior of the steel structure wall panel is provided with a heat-resistant material, and the heat-resistant material is an aluminum silicate board.

3. The ladle bottom pouring fume collection system according to claim 1, characterized in that: The buffer labyrinth sealing structure is sealed by means of a concave-convex structure, and a rubber pad is arranged at the concave part thereof.

4. The ladle bottom pouring fume collection system according to claim 1, characterized in that: The pouring sand box can be arranged in an underground pit, a semi-underground pit or on the ground.

5. The fume collection method of the ladle bottom pouring fume collection system according to any one of claims 1 to 4, characterized in that: The following steps are involved: a. Separate the first independent collection hood from the second independent collection hood, lift the ladle by the overhead crane into the pouring area, roughly locate the ladle bottom pouring valve and the sand box riser, and then close the two independent ladle bottom pouring collection hoods; b. Adjust the position of the bottom pouring collection hood, connect the exhaust port of the bottom pouring collection hood with the dust suction port of the main pipeline, and turn on the fan; c. Start the control motor at the reserved opening of the crane on the top of the ladle bottom pouring collection cover, sense the position of the crane through the crane sensing positioning device, move the sealing baffle to seal the reserved opening of the crane, and now the hanging ladle and the sand box are sealed in the ladle bottom pouring collection cover; d. The operator locates the ladle bottom pouring valve and the sand box riser, opens the ladle bottom pouring valve, injects molten steel into the sand box or steel mold, and starts pouring; e. After the first sand box pouring is completed, the hanging ladle moves inside the pouring collection cover at the bottom of the ladle along the reserved crane opening of the cover body under the command of the operator. Under the guidance of the crane induction positioning device, the motor is controlled to drive the double-sided sealing baffles to move correspondingly with the movement of the crane. After the ladle is positioned at the next pouring point, the second sand box pouring is carried out; f. When all the sand boxes in the ladle bottom pouring collection hood are poured, the smoke in the hood is emptied, the ladle bottom pouring collection hood moves on the walking track, and the smoke exhaust port moves to the next docking valve under the smoke exhaust main pipeline; g. After the docking is completed, move the ladle to the predetermined pouring position, open the exhaust main pipe docking valve, and enter the next pouring cycle; h. When the molten steel in the ladle is used up, the smoke in the pouring collection hood at the bottom of the ladle is emptied, the first independent collection hood and the second independent collection hood are separated, and the overhead crane is driven to move the ladle away for replacement.

6. The smoke collection method according to claim 5, characterized in that: When the sand box is arranged in the pouring pit before pouring, the pouring riser of the sand box is arranged in a straight line along the walking track direction of the pouring and collecting cover at the bottom of the ladle, and is arranged in the middle of the reserved overhead crane opening of the pouring and collecting cover at the bottom of the ladle.

7. The smoke collection method according to claim 5, characterized in that: The movement of the ladle bottom pouring collection cover and the overhead crane ladle must follow the instructions of the operator inside the cover, and they can move simultaneously or separately.

Images