Blast furnace forehearth door interlocking device

Abstract

This invention discloses an interlocking device for a blast furnace taphole door, belonging to the technical field of blast furnace ironmaking equipment. It includes a taphole safety door equipped with a door status detection switch, which is electrically connected to an intermediate relay control box. The intermediate relay control box is electrically connected to an equipment status indicator light and a local audible and visual alarm. A mechanical locking assembly is also provided between the taphole safety door and the door frame. This invention detects the closed / locked state of the taphole safety door and interlocks it with the operating permit circuits of the mud gun and taphole opening machine. Simultaneously, it utilizes a cleaning ring, cleaning teeth, and elastic reset pin structure to improve the reliability of the door locking under harsh operating conditions. This achieves forced locking of equipment in the taphole area, status indication, and audible and visual alarm linkage, effectively preventing accidental equipment activation when personnel enter the hazardous area. It has the advantages of high safety, reliable interlocking, and strong adaptability to the dusty environment in front of the furnace.

Description

Technical Field

[0001] This invention belongs to the technical field of blast furnace ironmaking equipment, and particularly relates to an interlocking device for the taphole door of a blast furnace. Background Technology

[0002] In the blast furnace ironmaking process, the taphole area is the core area for tapping, plugging, and related maintenance and cleaning operations. It is a high-risk work area due to its consistently high temperature, dust, noise, and frequent equipment operation. Common equipment in the taphole area includes tapping machines and mud guns. These devices require frequent start-ups, shutdowns, and reciprocating movements. If personnel accidentally enter the hazardous area or the equipment is started under unsafe conditions, it can easily lead to mechanical injuries, equipment collisions, high-temperature splashes, and other safety accidents. Therefore, strict requirements are placed on the safety isolation and interlocking control of this area.

[0003] Most existing blast furnace taphole doors or control doors only serve a simple physical isolation function and typically lack a complete and reliable safety interlock with equipment such as taphole opening machines and mud guns. When the taphole door is open, the relevant equipment may still be ready to start, making it difficult to effectively prevent dangerous actions through control logic. Especially when personnel enter the taphole area for inspection, maintenance, and cleaning operations, if communication between on-site personnel and operators in the control room is not timely or information transmission fails, accidental activation can easily occur, posing a significant safety hazard.

[0004] To address this issue, we propose an interlocking device for the taphole door in front of the blast furnace. Summary of the Invention

[0005] The purpose of this invention is to solve the problems in the prior art by proposing a blast furnace taphole interlocking device.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A blast furnace taphole door interlocking device includes a taphole safety door: The iron tap safety door is equipped with a door status detection switch, which is electrically connected to an intermediate relay control box. The intermediate relay control box is electrically connected to the equipment status indicator light and the on-site audible and visual alarm, and is used to connect in series with the operating permission circuit of the mud gun and the opening machine in front of the blast furnace. A mechanical locking assembly is also provided between the iron-mouth safety door and the door frame. The mechanical locking assembly includes a mounting base, a guide rail, a handle, a slot, a cleaning ring, cleaning teeth, a telescopic spring, a positioning plate, a positioning seat, and a pin. The mounting base is fixedly connected to the door frame or a fixed bracket. The guide rail is set on the mounting base. The pin is slidably connected to the guide rail. The handle is fixedly connected to the side wall of the pin. The slot is set on the side wall of the guide rail and is used to limit the handle. The positioning seat is fixedly connected to the iron-mouth safety door and is set opposite to the pin. The cleaning ring is set between the mounting base and the positioning seat. The cleaning teeth are set on the inner wall of the cleaning ring and contact the outer surface of the pin. The positioning plate is fixedly connected to the tail of the pin. The telescopic spring is connected between the mounting base and the positioning plate. The door status detection switch is set to correspond to the locking position of the mechanical locking assembly, so as to output an allow operation signal when the pin is inserted into the positioning seat and the iron gate safety door is closed in place, and output a prohibit operation signal when the iron gate safety door is open, not closed in place, or the pin is not locked in place.

[0007] This solution integrates the taphole safety door, door status detection switch, intermediate relay control box, equipment status indicator light, on-site audible and visual alarm, and mechanical locking components, and connects them in series with the mud gun and taphole machine operation permission circuit. This ensures that the equipment can only operate when the safety door is closed and properly locked. The equipment is forcibly locked when the door is open, not closed, or not locked. At the same time, it links status indication with audible and visual alarms, ensuring the safety of blast furnace operations from both mechanical and electrical perspectives.

[0008] Preferably, the end of the positioning seat facing the pin is provided with a flared guide structure, the inlet size of which is larger than the outer diameter of the pin, so that when there is a positional deviation during the closing of the iron gate safety door, the pin can still enter the positioning seat under the guidance.

[0009] The positioning seat of this solution adopts a flared guide structure, which can compensate for the positional displacement caused by door installation deviation, thermal expansion and contraction and hinge wear, so that the pin can be automatically guided to center and smoothly inserted into the positioning seat, improving the locking power and adaptability to working conditions, and avoiding the inability to lock due to misalignment.

[0010] Preferably, the cleaning ring is a ring-shaped or sleeve-shaped structure, and a plurality of cleaning teeth are distributed at intervals along the inner circumference of the cleaning ring. The cleaning teeth are inclined toward the pin axis and form a scraping contact with the outer surface of the pin to remove dust, slag or oxide particles from the pin surface.

[0011] The cleaning ring and the inclined cleaning teeth of this design continuously scrape away surface dust, slag and oxide particles when the pin reciprocates, preventing impurities from entering the guide rail and positioning seat and causing jamming and wear, thus significantly enhancing the operational stability and reliability of the device in a high-dust furnace environment.

[0012] Preferably, the telescopic spring is sleeved on the outer periphery of the pin or disposed on the rear side of the pin, one end of the telescopic spring is fixedly connected to the mounting base, and the other end is fixedly connected to the positioning plate.

[0013] The telescopic spring is stably sleeved on the outer periphery of the latch or installed at the tail, ensuring uniform force distribution and smooth movement. It can continuously provide elastic thrust to the latch, enabling the latch to automatically lock after the door is closed, ensuring timely and reliable locking, and preventing it from easily springing back and loosening.

[0014] Preferably, at least two slots are provided, corresponding to the unlocking position and the locking position of the pin respectively. The handle can be selectively engaged in the corresponding slot, thereby keeping the pin stably in the retracted state or the engaged state.

[0015] This solution uses a guide rail with dual slots corresponding to the unlocking and locking positions. The handle can be inserted and positioned to keep the latch stably in the retracted open state or the locked state. It is easy to operate, has a firm positioning, can resist on-site vibration, and avoids accidental unlocking or loosening.

[0016] Preferably, the equipment status indicator is a dual-color indicator, including at least a prohibited operation indication state and a permitted operation indication state; the on-site audible and visual alarm includes a warning light and an audible alarm unit, and emits an audible and visual alarm signal when the iron gate safety door is opened or not closed properly.

[0017] The solution features dual-color equipment status indicator lights that can intuitively distinguish between permitted and prohibited operating states. The on-site audible and visual alarm will simultaneously issue an audible and visual warning when the door is abnormal, achieving clear visibility of on-site and remote status and timely alerts for abnormalities, effectively reducing the risk of human error.

[0018] In summary, the technical effects and advantages of this invention are as follows: This invention integrates the mechanical locking structure of the taphole safety door with the door status detection switch, intermediate relay control box, equipment status indicator light, and on-site audible and visual alarm. This ensures that when someone enters the taphole area, or when the door is not closed or locked, the mud gun and taphole machine cannot obtain operating permission. This not only achieves physical isolation but also enables forced interlocking at the control level, significantly improving the inherent safety level of blast furnace operations. Attached Figure Description

[0019] Figure 1 This is a first-view structural diagram of the present invention; Figure 2 This is a schematic diagram of the second perspective structure of the present invention; Figure 3 for Figure 2 A magnified view of part A in the middle.

[0020] In the diagram: 1. Iron gate safety door; 2. Door status detection switch; 3. Intermediate relay control box; 4. Equipment status indicator light; 5. On-site audible and visual alarm; 6. Mounting base; 7. Guide rail; 8. Handle; 9. Slot; 10. Cleaning ring; 11. Cleaning teeth; 12. Telescopic spring; 13. Positioning plate; 14. Positioning seat; 15. Pin. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] like Figures 1 to 3 As shown, a blast furnace taphole door interlocking device includes a taphole safety door 1, a door status detection switch 2, an intermediate relay control box 3, an equipment status indicator light 4, a field audible and visual alarm 5, and a mechanical locking assembly for reliably locking the taphole safety door 1.

[0023] The taphole safety door 1 is located at the entrance to the hazardous work area in front of the blast furnace taphole, used to restrict personnel from entering the hazardous area without permission. The taphole safety door 1 can be a steel frame door structure, preferably a combination of a high-temperature resistant steel frame and heat-resistant steel plates. It can also be a fence door, a frame mesh door, or a closed door with an observation window, depending on the site layout. The taphole safety door 1 can be hinged or sliding, as long as it can cooperate with the mechanical locking components and door status detection switch 2 described later.

[0024] The door status detection switch 2 is located near the iron safety door 1 and the door frame or locking part. Its function is to detect whether the iron safety door 1 is in the closed and locked position. Preferably, the door status detection switch 2 can be a high-temperature resistant and dustproof limit switch, such as a heavy-duty roller limit switch; it can also be a magnetic proximity switch, Hall effect switch, or safety interlock switch. To improve reliability, the door status detection switch 2 is preferably located in the mating area between the latch 15 and the positioning seat 14, so that its detection object includes not only the closing action of the door body, but also the locking state after the latch 15 is actually inserted into the positioning seat 14, thereby avoiding the misjudgment that the door is safely closed based solely on the door panel being close together.

[0025] An intermediate relay control box 3 is located in the firing room. The intermediate relay control box 3 receives signals from the door status detection switch 2 and converts these signals into control signals for the operating permission circuits of the mud gun and the opening machine. The intermediate relay control box 3 may contain intermediate relays, safety relays, terminal blocks, a 24VDC or 220VAC power module, fuses, surge protectors, and necessary switching switches. Preferably, the intermediate relay control box 3 uses a dustproof and waterproof metal enclosure with a protection rating of IP54, IP55, or higher to adapt to the furnace environment. More preferably, the control method employs a power-off interlocking logic; that is, if the door status detection switch 2 does not output a "closed in place" signal, or if the door status detection circuit experiences an abnormality such as a broken wire, power failure, or component damage, the operating permission circuits of the mud gun and the opening machine are automatically disconnected, thereby preventing erroneous operation due to a single point of failure.

[0026] The equipment status indicator light 4 is used to visually display the current interlock status to the operator. Preferably, the equipment status indicator light 4 is a dual-color indicator light or a group of indicator lights, where a red light indicates "operation is prohibited or the door is not closed properly", and a green light indicates "operation is permitted or the door is closed and locked properly". The equipment status indicator light 4 can be installed on the outside of the iron gate, on the column near the door, at the control point of the blasting room, and on the control panel of the operating room to achieve synchronous display on site and remotely.

[0027] The on-site audible and visual alarm 5 is used to issue audible and visual warnings to on-site personnel when the iron tap safety door 1 is in the open state, not properly closed, or the interlocking circuit is in the locked state. The on-site audible and visual alarm 5 preferably includes a flashing warning light, a buzzer, and a voice module. The voice module can output prompts such as "Iron tap door open, equipment operation prohibited" or "Safety door not properly closed, do not start equipment," to improve on-site visibility and reduce misoperation.

[0028] In this embodiment, the mechanical locking assembly includes a mounting base 6, a guide rail 7, a handle 8, a slot 9, a cleaning ring 10, a cleaning tooth 11, a telescopic spring 12, a positioning plate 13, a positioning seat 14, and a pin 15.

[0029] Mounting base 6 is fixedly connected to the door frame, fixed post, or supporting component connected to the door frame, serving as the mounting base for pin 15. Mounting base 6 can be made of welded steel plate or cast steel, preferably Q235B, Q355B, or stainless steel. Guide rail 7 is provided on mounting base 6, and guide rail 7 is used to guide and limit the linear movement of pin 15. Guide rail 7 can be a grooved guide rail, a sleeve guide structure, or a sliding groove structure. To improve wear resistance, wear-resistant bushings, copper bushings, nylon guide bushings, or self-lubricating bushings can be provided between guide rail 7 and pin 15.

[0030] The latch 15 is slidably connected within the guide rail 7 and is the core component for achieving the mechanical locking of the iron gate safety door 1. The latch 15 is preferably a cylindrical, square, or rod-shaped component with a guide chamfer, and can be made of 45# steel, 40Cr tempered steel, or stainless steel. Its front end can be chamfered to further improve the smoothness of its entry into the positioning seat 14. A handle 8 is fixedly connected to the side wall of the latch 15, allowing the operator to manually pull or push the latch 15. The handle 8 can be fixed to the latch 15 by welding, threaded connection, or pin connection, and preferably has an external heat insulation layer or heat-resistant rubber sleeve to improve the comfort of hand operation.

[0031] The slot 9 is located on the side wall of the guide rail 7, and preferably has two or more limiting slots at different positions. The handle 8 can be inserted into the slot 9 to stably maintain the position of the pin 15. For example, when it is necessary to keep the iron gate 1 in the unlocked state for personnel passage or maintenance, the handle 8 can be pulled to the retracted position of the pin 15 and inserted into the corresponding slot 9; when the gate is closed, the engagement between the handle 8 and the slot 9 is released, and the pin 15 moves forward and inserts into the positioning seat 14 under the action of the telescopic spring 12, forming an automatic lock. If necessary, a corresponding slot 9 can also be provided in the locking position to improve vibration resistance and prevent the pin 15 from retracting due to environmental vibration.

[0032] The positioning seat 14 is fixedly connected to the blast furnace safety door 1 and is positioned opposite to the latch 15. The positioning seat 14 has a positioning hole or insertion cavity for the latch 15 to be inserted. To accommodate slight offsets in the blast furnace front door due to thermal expansion and contraction, hinge wear, or installation errors, the end of the positioning seat 14 facing the latch 15 is preferably configured with a flared guide structure. This flared structure can automatically correct and guide the latch 15 during door closing, ensuring that even with slight lateral or vertical errors, the latch 15 can smoothly enter the positioning seat 14, thereby improving the locking success rate.

[0033] A cleaning ring 10 is disposed between the mounting base 6 and the positioning base 14, and is located on the movement path of the pin 15. The cleaning ring 10 is preferably a ring structure fixed to the front end of the mounting base 6 or the outlet of the guide rail 7. Cleaning teeth 11 are disposed on the inner wall of the cleaning ring 10, and the number can be two, three, four, or more, preferably evenly spaced circumferentially. The cleaning teeth 11 can be made of elastic metal sheets, wear-resistant engineering plastic teeth, rubber scrapers, or composite material scrapers, and form a pressing contact with the outer surface of the pin 15. Thus, when the pin 15 reciprocates, the cleaning teeth 11 can scrape off dust, slag, and oxide particles adhering to the surface of the pin 15, preventing impurities from entering the interior of the guide rail 7 or the inner cavity of the positioning base 14 with the pin 15, reducing jamming and wear.

[0034] The positioning plate 13 is fixedly connected to the tail of the pin 15, and the telescopic spring 12 is connected between the mounting base 6 and the positioning plate 13. The telescopic spring 12 continuously applies an elastic pushing force to the pin 15 in the direction of the positioning base 14, so that the pin 15 can automatically move forward and insert into the positioning base 14 after the door is aligned. The positioning plate 13 is not only used to connect with the telescopic spring 12, but also serves to limit the spring, transmit force, and prevent the pin 15 from dislodging from the guide rail 7. The telescopic spring 12 is preferably made of fatigue-resistant spring steel, such as 65Mn spring steel or stainless steel spring wire, to adapt to frequent use conditions.

[0035] In this embodiment, the door status detection switch 2 is preferably set to correspond to the locking end position of the latch 15. For example, the door status detection switch 2 can be set on the mounting base 6 so that the door status detection switch 2 is triggered when the latch 15 is fully inserted into the positioning base 14 and reaches the predetermined end of its travel; or a sensing element can be set near the positioning base 14 so that the door status detection switch 2 can sense that the latch 15 has entered the positioning state. In this way, the intermediate relay control box 3 can only receive a real and valid permission signal when the iron gate safety door 1 is closed and the latch 15 has completed mechanical locking. This avoids the misjudgment that "the door panel appears to be closed, but is actually not locked".

[0036] The working principle is as follows: During normal maintenance, cleaning, or when personnel need to enter the hazardous area of ​​the taphole, the operator first pulls handle 8, causing pin 15 to retract along guide rail 7 away from positioning seat 14, and handle 8 can be engaged in the corresponding slot 9 to keep pin 15 in the unlocked position. At this time, taphole safety door 1 can be opened, and door status detection switch 2 outputs an open or not-in-position signal, which is sent to intermediate relay control box 3. Upon receiving the signal, intermediate relay control box 3 immediately cuts off the operating permission circuit of mud gun and taphole machine, preventing them from starting or performing dangerous actions. At the same time, equipment status indicator 4 switches to the prohibited operation state, and on-site audible and visual alarm 5 is activated, emitting audible, visual, and voice prompts to remind on-site personnel and remote operators that the taphole area is currently under safety protection.

[0037] After personnel leave the danger zone, close the iron safety door 1. As the door approaches the closed position, the positioning seat 14 gradually aligns with the latch 15. If there is a slight deviation in the door, the flared guide structure at the front end of the positioning seat 14 will guide and correct the latch 15. At this time, after releasing the engagement between the handle 8 and the slot 9, the telescopic spring 12 pushes the positioning plate 13 and the latch 15 forward, allowing the latch 15 to enter the positioning seat 14 via the cleaning ring 10. During the forward movement of the latch 15, the cleaning teeth 11 continuously scrape away dust, slag, and oxide particles from the surface of the latch 15 to prevent impurities from affecting the insertion accuracy and smoothness. After the latch 15 reaches the final locked position, the door status detection switch 2 is triggered, outputting a door closed and locked signal to the intermediate relay control box 3.

[0038] After receiving the signal that the door is closed and locked in place, the intermediate relay control box 3 restores the operating permission circuit for the mud gun and the tapping machine. The equipment status indicator 4 simultaneously switches to the permitted operating state, and the on-site audible and visual alarm 5 deactivates or outputs a safety deactivation prompt. At this point, a complete interlocking link is formed in the tapping area: "mechanical locking in place—electrical permission restored—equipment operational." If the tapping safety door 1 reopens, or if the latch 15 disengages from the locked position due to vibration, jamming, or other reasons, the door status detection switch 2 changes its output state, and the intermediate relay control box 3 immediately cuts off the equipment operating permission, achieving immediate locking.

[0039] It should be noted that in this embodiment, the mud gun and the opening machine can be existing blast furnace front equipment, and their control circuits generally have operation permission input terminals. In this application, the door status detection signal is connected in series with the above-mentioned permission circuit through the intermediate relay control box 3 to achieve interlocking. Preferably, the permission for mud gun rotation, propulsion, and mud-driving actions can be integrated with the permission for opening machine rotation, propulsion, and drilling actions into the interlocking circuit. Alternatively, depending on the on-site control architecture, only the most dangerous action circuit can be disconnected. Those skilled in the art can make conventional wiring adjustments based on the actual control system.

[0040] The cleaning ring 10 can be configured as a detachable structure to facilitate the periodic replacement of the cleaning teeth 11; a wear-resistant bushing can be added to the inner wall of the positioning seat 14; a tapered guide head can be added to the front end of the pin 15; the door status detection switch 2 can adopt a dual-switch redundant arrangement to further improve the interlocking reliability; the intermediate relay control box 3 can be connected to the PLC system to realize status uploading, historical record and remote monitoring, but even if it is not connected to the PLC, the mechanical-electrical interlocking function of this application can still be realized independently.

[0041] The mounting base 6 can also be fixed to the iron gate safety door 1, while the positioning base 14 is fixed to the door frame or fixed bracket. As long as the corresponding locking detection relationship is maintained between the pin 15, the positioning base 14, and the door status detection switch 2, it still falls within the protection scope of this invention. The guide rail 7 can be in the form of a U-shaped groove, a circular sleeve, or a double-sided guide plate; the slot 9 can be an open slot, a semi-circular slot, or a structure with a locking block; the cleaning teeth 11 can be a flexible scraper or a hard bristle structure. These are all equivalent variations of the concept of this application.

[0042] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A blast furnace taphole door interlocking device, comprising a taphole safety door (1), characterized in that: The iron tap safety door (1) is equipped with a door status detection switch (2), which is electrically connected to an intermediate relay control box (3). The intermediate relay control box (3) is electrically connected to the equipment status indicator (4) and the on-site sound and light alarm (5), and the intermediate relay control box (3) is used to connect in series with the operating permission circuit of the mud gun and the opening machine in front of the blast furnace. The iron-mouth safety door (1) is further provided with a mechanical locking assembly between itself and the door frame. The mechanical locking assembly includes a mounting base (6), a guide rail (7), a handle (8), a slot (9), a cleaning ring (10), a cleaning tooth (11), a telescopic spring (12), a positioning plate (13), a positioning seat (14), and a pin (15). The mounting base (6) is fixedly connected to the door frame or a fixed bracket. The guide rail (7) is set on the mounting base (6). The pin (15) is slidably connected to the guide rail (7). The handle (8) is fixedly connected to the pin (15). The side wall of the guide rail (7) has a slot (9) set on the side wall of the guide rail (7) and used to limit the handle (8). The positioning seat (14) is fixedly connected to the iron safety door (1) and is set opposite to the pin (15). The cleaning ring (10) is set between the mounting seat (6) and the positioning seat (14). The cleaning teeth (11) are set on the inner wall of the cleaning ring (10) and contact the outer surface of the pin (15). The positioning plate (13) is fixedly connected to the tail of the pin (15). The telescopic spring (12) is connected between the mounting seat (6) and the positioning plate (13). The door status detection switch (2) is set to correspond to the locking position of the mechanical locking assembly, so as to output an allow operation signal when the pin (15) is inserted into the positioning seat (14) and the iron gate safety door (1) is closed in place, and output a prohibit operation signal when the iron gate safety door (1) is open, not closed in place or the pin (15) is not locked in place.

2. The blast furnace taphole interlocking device according to claim 1, characterized in that, The positioning seat (14) has a flared guide structure at one end facing the pin (15). The inlet size of the flared guide structure is larger than the outer diameter of the pin (15) so that when there is a positional deviation during the closing process of the iron safety door (1), the pin (15) can still enter the positioning seat (14) under the guidance.

3. The blast furnace taphole interlocking device according to claim 1, characterized in that, The cleaning ring (10) is a ring-shaped or sleeve-shaped structure. A number of cleaning teeth (11) are distributed at intervals along the inner circumference of the cleaning ring (10). The cleaning teeth (11) are inclined toward the axis of the pin (15) and form a scraping contact with the outer surface of the pin (15) to remove dust, slag or oxide particles from the surface of the pin (15).

4. The blast furnace taphole interlocking device according to claim 1, characterized in that, The telescopic spring (12) is sleeved on the outer periphery of the pin (15) or set on the rear side of the pin (15). One end of the telescopic spring (12) is fixedly connected to the mounting base (6), and the other end is fixedly connected to the positioning plate (13).

5. The blast furnace taphole interlocking device according to claim 1, characterized in that, The slot (9) has at least two slots, which correspond to the unlocking position and the locking position of the pin (15) respectively. The handle (8) can be selectively engaged in the corresponding slot (9) so as to keep the pin (15) stably in the retracted state or the engaged state.

6. The blast furnace taphole interlocking device according to claim 1, characterized in that, The equipment status indicator (4) is a dual-color indicator, including at least a prohibited operation indication state and a permitted operation indication state; the on-site audible and visual alarm (5) includes a warning light and an audible alarm unit, and emits an audible and visual alarm signal when the iron gate safety door (1) is opened or not closed in place.

Images