CN115368148A - Novel method for prolonging service life of furnace roller of roller-hearth heating furnace - Google Patents
Novel method for prolonging service life of furnace roller of roller-hearth heating furnace Download PDFInfo
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- CN115368148A CN115368148A CN202210843069.5A CN202210843069A CN115368148A CN 115368148 A CN115368148 A CN 115368148A CN 202210843069 A CN202210843069 A CN 202210843069A CN 115368148 A CN115368148 A CN 115368148A
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- roller
- furnace
- furnace roller
- ceramic fiber
- adhesive
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- 238000010438 heat treatment Methods 0.000 title claims abstract description 22
- 238000000034 method Methods 0.000 title claims abstract description 22
- 239000000853 adhesive Substances 0.000 claims abstract description 24
- 230000001070 adhesive effect Effects 0.000 claims abstract description 24
- 239000002184 metal Substances 0.000 claims abstract description 18
- 238000010276 construction Methods 0.000 claims abstract description 11
- 230000000694 effects Effects 0.000 claims abstract description 10
- 238000009413 insulation Methods 0.000 claims abstract description 10
- 230000008569 process Effects 0.000 claims abstract description 8
- 239000000919 ceramic Substances 0.000 claims description 42
- 239000000835 fiber Substances 0.000 claims description 33
- 239000011347 resin Substances 0.000 claims description 14
- 229920005989 resin Polymers 0.000 claims description 14
- 238000004873 anchoring Methods 0.000 claims description 12
- 238000003466 welding Methods 0.000 claims description 6
- 238000005452 bending Methods 0.000 claims description 5
- 239000011230 binding agent Substances 0.000 claims description 5
- 229920000742 Cotton Polymers 0.000 claims description 3
- 239000007767 bonding agent Substances 0.000 claims description 3
- 230000005855 radiation Effects 0.000 claims description 3
- 238000005507 spraying Methods 0.000 claims description 3
- 238000004804 winding Methods 0.000 claims description 3
- 239000004927 clay Substances 0.000 claims description 2
- 239000011248 coating agent Substances 0.000 claims description 2
- 238000000576 coating method Methods 0.000 claims description 2
- 229910000831 Steel Inorganic materials 0.000 abstract description 12
- 239000010959 steel Substances 0.000 abstract description 12
- 238000005265 energy consumption Methods 0.000 abstract description 4
- 238000004901 spalling Methods 0.000 abstract description 2
- 238000005266 casting Methods 0.000 description 11
- 239000011819 refractory material Substances 0.000 description 4
- 239000000498 cooling water Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 238000001816 cooling Methods 0.000 description 2
- 238000005096 rolling process Methods 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 210000000988 bone and bone Anatomy 0.000 description 1
- 230000003139 buffering effect Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000009991 scouring Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/66—Monolithic refractories or refractory mortars, including those whether or not containing clay
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/71—Ceramic products containing macroscopic reinforcing agents
- C04B35/78—Ceramic products containing macroscopic reinforcing agents containing non-metallic materials
- C04B35/80—Fibres, filaments, whiskers, platelets, or the like
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
- F27B9/14—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment
- F27B9/20—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path tunnel furnace
- F27B9/24—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path tunnel furnace being carried by a conveyor
- F27B9/2407—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path tunnel furnace being carried by a conveyor the conveyor being constituted by rollers (roller hearth furnace)
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Tunnel Furnaces (AREA)
- Heat Treatments In General, Especially Conveying And Cooling (AREA)
Abstract
The invention discloses a new method for prolonging the service life of a roller hearth type heating furnace roller, which comprises the following steps: (1) improving the adhesion and tensile strength of the adhesive; and (2) optimizing the construction process of the heat insulation layer. The invention aims to provide a novel method for prolonging the service life of a furnace roller of a roller hearth heating furnace, which improves the bonding strength of a heat-insulating layer and a metal structural member of the furnace roller, reduces the spalling to the maximum extent, improves the bonding time of the heat-insulating layer and the metal structural member of the furnace roller, and is a main method for reducing the burning loss of the furnace roller, prolonging the service life of the furnace roller, improving the heating effect and reducing the heating energy consumption of ton steel.
Description
Technical Field
The invention relates to a novel method for prolonging the service life of a furnace roller of a roller-hearth heating furnace.
Background
The furnace roller is the most important equipment in a roller hearth type heating furnace (CSP-compact strip steel production line), is a through shaft water-cooling roller, has the main functions of serving as heating and buffering equipment between a rolling mill and a casting machine, supports a casting blank in the furnace through the furnace roller, and finishes the conveying task of the casting blank in the furnace through the forward and reverse rotation and rotation speed regulation of the furnace roller and the friction drive of a roller ring and a thin plate casting blank piece. The number of lines is extremely large. The heat-insulating plate mainly comprises a metal structural part and a refractory material heat-insulating layer (hereinafter referred to as a heat-insulating layer). The metal structural part mainly comprises a supporting roll shaft, a water-cooled steel pipe, a metal roll body and a heat-resistant metal roll collar. The heat insulating layer is made of refractory material between the roll collars. The non-contact part of the furnace roller and the casting blank is completely wrapped by a refractory material, so that the support strength and rigidity of the furnace roller under the high-temperature use condition are ensured, and the water-cooling heat loss of the furnace roller is reduced. Therefore, the heat insulation layer of the furnace roller has the worst working environment, and is required to bear high temperature, furnace gas scouring and corrosion, vibration impact generated when a casting blank is contacted with a roller ring and the centrifugal action of the furnace roller on the heat insulation layer in the acceleration and deceleration process.
The heat insulation layer is peeled off, so that the furnace roller metal structural part is directly exposed in high-temperature furnace gas and is subjected to flame roasting by a burner, the oxidation and burning loss of the metal part are increased, the strength and the bearing performance are greatly reduced, and the bending phenomenon is easily generated under the impact and heavy pressing of a casting blank. Meanwhile, the heat insulation layer is peeled off, the metal structural part is directly exposed in the hearth, a strong heat absorption effect is generated, the return water temperature of cooling water in the furnace roller is greatly increased, a large amount of heat energy applied to heating of a casting blank is taken away, and the objective facts that the heating effect of the casting blank is poor and the energy consumption per ton of steel is increased are caused.
Disclosure of Invention
The invention aims to provide a novel method for prolonging the service life of a furnace roller of a roller hearth heating furnace, which improves the bonding strength of a heat-insulating layer and a metal structural member of the furnace roller, reduces the spalling to the maximum extent, improves the bonding time of the heat-insulating layer and the metal structural member of the furnace roller, and is a main method for reducing the burning loss of the furnace roller, prolonging the service life of the furnace roller, improving the heating effect and reducing the heating energy consumption of ton steel.
In order to solve the technical problem, the invention adopts the following technical scheme:
the invention relates to a new method for prolonging the service life of a roller hearth type heating furnace roller, which comprises the following steps:
(1) Increase the adhesive and tensile strength of the adhesive
Replacing high-temperature clay with resin ceramic binder to improve adhesiveness;
before the resin ceramic adhesive is used, ceramic cellucotton is added and broken, long fibers in the cellucotton and the resin adhesive are fully stirred, and the adhesion and tensile strength of the adhesive are increased;
(2) Optimized thermal insulation layer construction process
(2.1) welding anchoring nails on the smooth furnace roller structural member at intervals of 50-80 mm;
(2.2) smearing a resin ceramic adhesive which is added with ceramic fiber cotton and is uniformly stirred on the furnace roller metal structural part;
(2.3) according to a seamless construction mode, after a layer of ceramic fiber rope (heat-resistant steel wire ceramic fiber rope) is wound while tensioning, oppositely bending the welded anchoring nails into an L shape, and compacting the L shape on the first layer of ceramic fiber rope;
(2.4) after the first layer is compacted, spraying resin ceramic binder, and then continuously laying ceramic fiber ropes until the distance between the ceramic fiber ropes and the roll collar is 8mm according to the requirements of the step (2.3); in the construction process, the bonding agent is ensured to be filled in the rope gap, and after each layer is laid, the welding anchoring nails are bent oppositely into an L shape if necessary, and the ceramic fiber rope is compacted;
(2.5) winding the ceramic fiber rope to a position 20mm below the surface of the roll collar, smearing a layer of adhesive with the thickness of 3-7mm on the surface of the ceramic fiber rope, and then sticking a layer of ceramic fiber blanket with the thickness of 5-15mm to further block heat radiation and enhance the heat insulation effect;
and (2.6) baking the constructed furnace roller for a certain time, and then using the furnace roller on line.
Further, the anchoring nails of 8 x 100mm are used in the step (2.1).
Furthermore, a phi 15mm ceramic fiber rope is adopted in the step (2.3).
Further, in the step (2.6), the mixture is baked in a baking furnace at the temperature of 100-200 ℃ for 4-6 hours.
Compared with the prior art, the invention has the beneficial technical effects that:
the invention can be popularized to a steel rolling production line with a roller-hearth heating furnace, can greatly reduce the heating energy consumption of ton steel, improve the service life of the furnace roller, and simultaneously reduce the slab deviation and steel piling accidents caused by burning loss and bending of the furnace roller. The manufacturing method of the refractory material of the heat-insulating layer of the furnace roller on line is only required to be changed, so that the purpose of the on-line service life of the furnace roller can be achieved, and the cost is low. Has wide application prospect.
Drawings
The invention is further illustrated in the following description with reference to the drawings.
FIG. 1 is a view showing a structure of a metal structural member of a furnace roller
FIG. 2 is a schematic view of the assembly of the metal structural members of the furnace roller
FIG. 3 is a partial enlarged view of the interior of the box of FIG. 2
Fig. 4 isbase:Sub>A sectional view taken along linebase:Sub>A-base:Sub>A of fig. 2.
Description of reference numerals: 1. a furnace roller metal structural member; 2. a ceramic fiber rope; 3. and (6) anchoring nails.
Detailed Description
As shown in fig. 1 to 4, a new method for prolonging the service life of a roller hearth heating furnace roller comprises the following steps:
(1) Improving the adhesive and tensile strength of the adhesive
Refractory mortar is used as a resin ceramic binder, so that the adhesion is improved;
before the resin ceramic adhesive is used, ceramic cellucotton is added before stirring, the cellucotton is smashed, long fibers in the cellucotton and the resin adhesive are fully stirred, and the adhesion and tensile strength of the bone adhesive are increased;
(2) Optimized refractory layer construction process
(2.1) welding phi 8 x 100mm anchoring nails 3 on the smooth furnace roller metal structural part 1 at intervals of 50-80 mm;
(2.2) coating a resin ceramic adhesive which is added with ceramic fiber cotton and uniformly stirred on the furnace roller metal structural part 1;
(2.3) according to a seamless construction mode, after a layer of phi 15mm heat-resistant steel wire ceramic fiber rope 2 is wound while tensioning (the rope gap is filled with an adhesive during the first layer construction, the strength of a bottom layer is further improved), oppositely bending the welded anchoring nails 3 into an L shape, and compacting the L shape on the first layer of ceramic fiber rope 2;
and (2.4) after the first layer is compacted, spraying the improved adhesive, and then continuously laying the ceramic fiber rope 2 to a position 8mm away from the roller ring according to the requirement of the step (3). In the construction process, the bonding agent is ensured to be filled in the rope gap, and after each layer is paved, the welding anchoring nails 3 are bent oppositely into an L shape if necessary, and the ceramic fiber rope 2 is compacted;
(2.5) winding the fiber rope to a position 15mm below the surface of the roller ring, smearing a layer of adhesive with the thickness of about 5mm on the surface of the fiber rope, and then attaching a layer of ceramic fiber blanket with the thickness of 10mm to further block heat radiation and enhance the heat insulation effect;
(2.6) placing the constructed furnace roller into a special baking furnace, baking for 4-6 hours at the temperature of 100-200 ℃, and then using on line;
the invention is used for the heating section of the roller-hearth heating furnace in a steel sheet-covered factory, the furnace roller rotates at the running speed of a casting blank under the condition of the maximum temperature of 1200 ℃, the effect is good, the service life is more than 12 months, and the return water temperature of the furnace roller cooling water is 36 ℃.
The invention is used for the roller-hearth heating furnace section of a steel sheet-covered factory, the furnace roller rotates according to the running speed of a casting blank under the condition of the maximum temperature of 1200 ℃, the effect is good, the service life is more than 12, and the return water temperature of furnace roller cooling water is 36 ℃.
The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.
Claims (4)
1. A new method for prolonging the service life of a roller hearth type heating furnace roller is characterized by comprising the following steps:
(1) Improving the adhesive and tensile strength of the adhesive
Replacing high-temperature clay with resin ceramic binder to improve adhesiveness;
before the resin ceramic adhesive is used, ceramic cellucotton is added and broken, long fibers in the cellucotton and the resin adhesive are fully stirred, and the adhesion and tensile strength of the adhesive are increased;
(2) Optimized thermal insulation layer construction process
(2.1) welding anchoring nails on the smooth furnace roller structural member at intervals of 50-80 mm;
(2.2) coating a resin ceramic adhesive which is added with ceramic fiber cotton and uniformly stirred on the furnace roller metal structural part;
(2.3) according to a seamless construction mode, after a layer of ceramic fiber rope is wound while tensioning, oppositely bending the welded anchoring nails into an L shape, and compacting on the first layer of ceramic fiber rope;
(2.4) after the first layer is compacted, spraying resin ceramic binder, and then continuously laying ceramic fiber ropes until the distance between the ceramic fiber ropes and the roll collar is 8mm according to the requirements of the step (2.3); in the construction process, the bonding agent is ensured to be filled in the rope gap, and after each layer is laid, the welding anchoring nails are bent oppositely into an L shape if necessary, and the ceramic fiber rope is compacted;
(2.5) winding the ceramic fiber rope to a position 20mm below the surface of the roll collar, smearing a layer of adhesive with the thickness of 3-7mm on the surface of the ceramic fiber rope, and then sticking a layer of ceramic fiber blanket with the thickness of 5-15mm to further block heat radiation and enhance the heat insulation effect;
and (2.6) baking the constructed furnace roller for a certain time, and then using the furnace roller on line.
2. A new method for increasing the service life of a roller hearth furnace roller according to claim 1, wherein said step (2.1) uses anchoring nails of 8 x 100mm.
3. The new method for prolonging the service life of the furnace roller of the roller hearth furnace according to claim 1, wherein a ceramic fiber rope with the diameter of 15mm is adopted in the step (2.3).
4. The new method for improving the service life of the roller hearth furnace roller according to claim 1, wherein in the step (2.6), the roller hearth furnace roller is baked in a baking furnace at a temperature of 100-200 ℃ for 4-6 hours.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210843069.5A CN115368148A (en) | 2022-07-18 | 2022-07-18 | Novel method for prolonging service life of furnace roller of roller-hearth heating furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210843069.5A CN115368148A (en) | 2022-07-18 | 2022-07-18 | Novel method for prolonging service life of furnace roller of roller-hearth heating furnace |
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| CN115368148A true CN115368148A (en) | 2022-11-22 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202210843069.5A Pending CN115368148A (en) | 2022-07-18 | 2022-07-18 | Novel method for prolonging service life of furnace roller of roller-hearth heating furnace |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104673330A (en) * | 2013-11-27 | 2015-06-03 | 五冶集团上海有限公司 | 7.63 m coke oven door frame ceramic fiber rope tamping apparatus and applications thereof |
| CN206272881U (en) * | 2016-12-29 | 2017-06-20 | 盐城市龙科电器有限公司 | Heat-conducting oil furnace electromagnetic induction heater novel heat insulation and preservation layer |
| US20170275731A1 (en) * | 2014-10-03 | 2017-09-28 | Jfe Steel Corporation | Hearth roll and continuous annealing facility |
| CN111811282A (en) * | 2020-07-01 | 2020-10-23 | 武汉钢铁有限公司 | Heat insulation protective layer structure of water-cooling furnace roller and preparation method thereof |
| CN215103412U (en) * | 2021-03-25 | 2021-12-10 | 邯郸钢铁集团有限责任公司 | Heating furnace hearth roll |
| CN217709613U (en) * | 2022-06-01 | 2022-11-01 | 包头钢铁（集团）有限责任公司 | Furnace roller heat-insulating layer fireproof structure of roller-hearth heating furnace |
-
2022
- 2022-07-18 CN CN202210843069.5A patent/CN115368148A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104673330A (en) * | 2013-11-27 | 2015-06-03 | 五冶集团上海有限公司 | 7.63 m coke oven door frame ceramic fiber rope tamping apparatus and applications thereof |
| US20170275731A1 (en) * | 2014-10-03 | 2017-09-28 | Jfe Steel Corporation | Hearth roll and continuous annealing facility |
| CN206272881U (en) * | 2016-12-29 | 2017-06-20 | 盐城市龙科电器有限公司 | Heat-conducting oil furnace electromagnetic induction heater novel heat insulation and preservation layer |
| CN111811282A (en) * | 2020-07-01 | 2020-10-23 | 武汉钢铁有限公司 | Heat insulation protective layer structure of water-cooling furnace roller and preparation method thereof |
| CN215103412U (en) * | 2021-03-25 | 2021-12-10 | 邯郸钢铁集团有限责任公司 | Heating furnace hearth roll |
| CN217709613U (en) * | 2022-06-01 | 2022-11-01 | 包头钢铁（集团）有限责任公司 | Furnace roller heat-insulating layer fireproof structure of roller-hearth heating furnace |
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Application publication date: 20221122 |