Method for on-line quick replacement of furnace roller of heat treatment furnace

Abstract

This invention relates to the technical field of metallurgical heat treatment furnace maintenance methods, and discloses an online rapid replacement method for furnace rollers in heat treatment furnaces, comprising the following steps: Step 1, controlling the heat treatment furnace to a suitable working state; Step 2, replacing the cable, burner, and supporting pipeline above the furnace roller position; Step 4, removing the bearing seats at both ends of the furnace roller, and matching the broken roller removal fixture with the furnace bottom roller drive and passive end shaft head. The online rapid replacement and maintenance method for furnace rollers in heat treatment furnaces eliminates the need for maintenance personnel to enter the furnace, significantly reduces the furnace temperature drop, avoids energy losses caused by furnace shutdowns for maintenance, greatly shortens maintenance time, improves the working environment for replacing furnace bottom rollers, reduces the labor intensity of employees, solves a long-standing production problem, minimizes the production impact of replacing furnace bottom rollers, ensures steel plate output, has significant economic benefits, and has great potential for widespread application.

Description

Technical Field

[0001] This invention relates to the technical field of metallurgical heat treatment furnace maintenance methods, specifically a method for online rapid replacement of furnace rollers in a heat treatment furnace. Background Technology

[0002] Heat treatment is a crucial step in steel production, and the furnace rollers and radiant tubes of the heat treatment furnace are essential components of the furnace zone for heat treatment of steel plates. The steel plate moves along the bottom rollers in the heat treatment furnace, and the bottom rollers are heated simultaneously with the steel plate. During heat treatment, the bottom rollers frequently break due to thermal expansion and other factors. When multiple bottom rollers break, or when several bottom rollers break consecutively, the steel plate is prone to slanting or jamming, preventing it from passing through the furnace normally. This is especially problematic when producing 6-8mm thick steel plates, which are relatively thin and prone to tipping over, thus hindering production.

[0003] Current technology for handling such faults generally requires furnace shutdown for maintenance and replacement of the furnace rolls. This necessitates personnel entering the furnace chamber to install supports and hoists at the bottom of the roll to be replaced, leveling it before removing the broken roll. Replacing the roll requires approximately eight maintenance personnel. Furthermore, replacing the radiant tubes and furnace rolls must be carried out while the furnace is shut down. Cooling down for maintenance takes at least 72 hours, and the furnace temperature must be reduced to around 50°C before personnel can enter the furnace to replace the bottom rolls. The high furnace temperature also hinders maintenance work. Replacing multiple bottom rolls takes 2-3 days, and heating up takes another 24 hours. Therefore, each maintenance operation takes a total of 5-6 days. This prolonged downtime disrupts continuous production, reduces steel plate output, and affects timely delivery to customers. Additionally, heat loss during shutdown and energy consumption during reactivation increase the cost per ton of steel, negatively impacting the company's economic performance. Summary of the Invention

[0004] (a) Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this invention provides a method for online rapid replacement of furnace bottom rollers in heat treatment furnaces. Its advantages are: it enables online maintenance of individual furnace bottom rollers, shortens maintenance time, and minimizes the impact of replacing furnace bottom rollers on production.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for online rapid replacement of furnace rollers in a heat treatment furnace, comprising the following steps:

[0008] Step 1: Control the heat treatment furnace to achieve the appropriate working condition;

[0009] Step 2: Replace the cable, burner, and related piping above the furnace roller position;

[0010] Step 3: Remove and replace the furnace roller drive motor, transmission shaft and connector, and place the corresponding support rollers to support and push the new rollers before they enter the furnace.

[0011] Step 4: Remove the bearing seats at both ends of the furnace roller. Match the broken roller removal tool with the drive and passive end shaft of the furnace bottom roller. Weld the shaft end face to the end face of the removal tool to fix it, so that the broken roller and the removal tool are integrated into one piece.

[0012] Step 5: Operate the overhead crane to remove the broken roller from the furnace, and then lower the prepared fireproof curtain to seal and insulate the furnace.

[0013] Step 6: Hoist the new furnace roller spare parts onto the non-drive roller in advance, and adjust the furnace roller axis elevation through the screw mechanism at the bottom of the roller;

[0014] Step 7: Connect the new furnace roller to the special hoisting and traction tool for installing the new roller. After installing the new roller, the special hoisting and traction tool will push the roller conveyor and the special hoisting and traction tool for the new roller to enter the non-drive side through the idler roller.

[0015] Step 8: Install extension rods at both ends of the furnace roller, and push the heat-insulating and heat-resistant cone sleeve towards the roller neck position through the extension rods. Use a hoist to lift and align the furnace roller, and insert the heat-insulating and heat-resistant cone sleeve into the furnace wall assembly bearing seat.

[0016] Step 9: Hot-fitting the assembly, installing the geared motor, and connecting the drive shaft;

[0017] Step 10: Remove temporary lifting beams and other facilities, clean up the site, and test run the vehicle.

[0018] Preferably, in step one, the heat treatment furnace is shut off and cooled to below 500°C.

[0019] Preferably, in step two, thermal insulation protection measures should also be taken to prevent the hot air inside the furnace from burning other equipment at the moment the furnace rollers are removed.

[0020] Preferably, in step five, the overhead crane is used to suspend the lifting point of the broken roller removal tool and move the overhead crane horizontally outward.

[0021] Preferably, in step seven, when the end of the special hoisting and traction tool for the new roller extends out of the furnace wall on the transmission side, a hoist is used to guide the tool onto the idler roller on the transmission side, and it continues to move to the installation position.

[0022] Preferably, in step seven, the new roller is installed using a segmented connection method with a mother and daughter sleeve.

[0023] Preferably, in step three, the corresponding support rollers are placed at horizontal positions on the non-drive side and the drive side of the furnace rollers.

[0024] Preferably, in step one, the furnace pressure also needs to be controlled to a slightly negative pressure.

[0025] (III) Beneficial Effects

[0026] Compared with the prior art, the present invention provides a method for online rapid replacement of furnace rollers in heat treatment furnaces, which has the following beneficial effects:

[0027] This method for online rapid replacement of furnace rollers in heat treatment furnaces eliminates the need for maintenance personnel to enter the furnace, significantly reduces the rate of furnace temperature drop, avoids energy losses caused by furnace shutdowns for maintenance, greatly shortens maintenance time, improves the working environment for replacing furnace bottom rollers, reduces the labor intensity of employees, solves a long-standing production problem, minimizes the impact of furnace bottom roller replacement on production, ensures steel plate output, and has significant economic benefits and great value for widespread application. Attached Figure Description

[0028] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0029] Figure 1 This is a schematic diagram of the old roller removal tooling of the present invention;

[0030] Figure 2 This is a schematic diagram of the new roller mounting fixture of the present invention;

[0031] Figure 3 This is a schematic diagram of the installation process of the new roller of the present invention.

[0032] In the diagram: 1. First segment; 2. First intermediate segment; 3. Second intermediate segment; 4. Last segment. Detailed Implementation

[0033] 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.

[0034] like Figure 1-3 As shown, the present invention provides a method for online rapid replacement of furnace rollers in a heat treatment furnace, comprising the following steps:

[0035] Step 1: Stop the gas supply to the heat treatment furnace and cool it down to below 500℃, with the furnace pressure at a slightly negative level;

[0036] Step 2: Replace the cables, burners and related pipelines above the furnace roller position, and take thermal insulation protection measures to prevent the hot gas in the furnace from burning other equipment when the furnace roller is removed.

[0037] Step 3: Remove and replace the furnace roller drive motor, drive shaft and connector. Place the corresponding support rollers on the non-drive side and drive side of the furnace roller at the horizontal position to support and push the new roller before it enters the furnace.

[0038] Step 4: Remove the bearing seats at both ends of the furnace roller, and remove the broken roller removal fixture (such as...). Figure 1 As shown, the shaft end face is matched with the furnace bottom roller drive and the passive end shaft head. The shaft end face is welded and fixed to the end face of the dismantling tool, so that the broken roller and the dismantling tool are integrated. Since the specific location of the broken roller cannot be confirmed, the first trial lifting is carried out after the dismantling tool is installed. By observing the tilt direction of the broken roller, the counterweight at the rear of the tool is appropriately added or removed until the dismantling tool and the broken roller are in a horizontal state.

[0039] Step 5: Use an overhead crane to lift the lifting point of the broken roller removal tool, move the overhead crane horizontally outward to remove the broken roller from the furnace, and then lower the prepared fireproof door curtain to seal and insulate the furnace.

[0040] Step Six: Hoist the new furnace roller spare parts onto the non-drive idler rollers in advance, and adjust the furnace roller axis elevation using the screw mechanism at the bottom of the idler rollers.

[0041] Step 7: Place the new furnace roller and the special hoisting and traction tool for installing the new roller (such as...) Figure 2 (As shown) Connection: The hoisting and traction tool is precisely counterweighted according to the weight of a single furnace bottom roller (1492.2KG), and adopts a segmented connection method of mother and daughter sleeves. (The hoisting and traction tool consists of four sleeves. The inner hole size of the first sleeve is processed according to the outer diameter of the roller shaft on the non-drive side of the roller table. The end face is fixed with pressure cap bolts. The remaining three sleeves are 3 meters each, and the connection length can be adjusted according to the maintenance position.) After the special hoisting and traction tool for the new roller is installed, the roller table and the special hoisting and traction tool for the new roller are pushed into the non-drive side by the idler roller. When the end of the special hoisting and traction tool for the new roller extends out of the furnace wall on the drive side, the hoist is used to guide the tool onto the idler roller on the drive side and continue to move to the installation position.

[0042] Step 8: Install extension rods at both ends of the furnace roller, and push the heat-insulating and heat-resistant cone sleeve towards the roller neck position through the extension rods. Use a hoist to lift and align the furnace roller, and insert the heat-insulating and heat-resistant cone sleeve into the furnace wall assembly bearing seat.

[0043] Step 9: Hot-fitting the assembly, installing the geared motor, and connecting the drive shaft.

[0044] Step 10: Remove temporary lifting beams and other facilities, clean up the site, and test run the vehicle.

Claims

1. A method for rapid online replacement of furnace rollers in a heat treatment furnace, characterized in that, Includes the following steps: Step 1: Control the heat treatment furnace to achieve the appropriate working condition; Step 2: Replace the cable, burner, and related piping above the furnace roller position; Step 3: Remove and replace the furnace roller drive motor, transmission shaft and connector, and place the corresponding support rollers to support and push the new rollers before they enter the furnace. Step 4: Remove the bearing seats at both ends of the furnace roller. Match the broken roller removal tool with the drive and passive end shaft of the furnace bottom roller. Weld the shaft end face to the end face of the removal tool to fix it, so that the broken roller and the removal tool are integrated into one piece. Step 5: Operate the overhead crane to remove the broken roller from inside the furnace, and then lower the prepared fireproof curtain to seal and insulate the furnace. Step 6: Hoist the new furnace roller spare parts onto the non-drive rollers in advance, and adjust the furnace roller axis elevation through the screw mechanism at the bottom of the rollers; Step 7: Connect the new furnace roller to the special hoisting and traction tool for installing the new roller. After installing the new roller, the special hoisting and traction tool will push the roller conveyor and the special hoisting and traction tool for the new roller to enter the non-drive side through the idler roller. Step 8: Install extension rods at both ends of the furnace roller, and push the heat-insulating and heat-resistant cone sleeve towards the roller neck position through the extension rods. Use a hoist to lift and align the furnace roller, and insert the heat-insulating and heat-resistant cone sleeve into the furnace wall assembly bearing seat. Step 9: Hot-fitting the assembly, installing the geared motor, and connecting the drive shaft; Step 10: Dismantle the temporary lifting beam facilities, clean up the site, and conduct a test run.

2. The method for online rapid replacement of furnace rollers in a heat treatment furnace according to claim 1, characterized in that: In step one, the heat treatment furnace is shut off and cooled to below 500°C.

3. The method for online rapid replacement of furnace rollers in a heat treatment furnace according to claim 1, characterized in that: In step two, it is also necessary to take measures to protect against heat and moisture damage to prevent the hot air inside the furnace from burning other equipment when the furnace rollers are removed.

4. The method for online rapid replacement of furnace rollers in a heat treatment furnace according to claim 1, characterized in that: In step five, the overhead crane is used to suspend the lifting point of the broken roller removal tool and move the overhead crane horizontally outward.

5. The method for online rapid replacement of furnace rollers in a heat treatment furnace according to claim 1, characterized in that: In step seven, when the end of the special hoisting and traction tool for the new roller extends out of the furnace wall on the transmission side, a hoist is used to guide the tool onto the idler roller on the transmission side, and it continues to move to the installation position.

6. The method for online rapid replacement of furnace rollers in a heat treatment furnace according to claim 1, characterized in that: In step seven, the new roller is installed using a segmented connection method with a mother and daughter sleeve.

7. The method for online rapid replacement of furnace rollers in a heat treatment furnace according to claim 1, characterized in that: In step three, the corresponding support rollers are placed at the horizontal positions of the furnace rollers on the non-drive side and the drive side.

8. The method for online rapid replacement of furnace rollers in a heat treatment furnace according to claim 1, characterized in that: In step one, the furnace pressure also needs to be controlled to a slightly negative pressure.

Images