CN104831053A - Electrical steel annealing and heating support method - Google Patents
Electrical steel annealing and heating support method Download PDFInfo
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- CN104831053A CN104831053A CN201510270536.XA CN201510270536A CN104831053A CN 104831053 A CN104831053 A CN 104831053A CN 201510270536 A CN201510270536 A CN 201510270536A CN 104831053 A CN104831053 A CN 104831053A
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Abstract
The invention discloses an electrical steel annealing and heating support method which comprises a furnace body (2), wherein the furnace body (2) comprises a heating zone (3), a soaking zone (4), a support roller (6) and a plasma nozzle (5); the heating zone (3) and the soaking zone (4) are used for annealing a steel strip; the support roller (6) is used for supporting the steel strip in the furnace body (2); the plasma nozzle (5) is used for ejecting a gas from the steel strip and supporting the steel strip; and the steel strip is separated from the support roller (6) in the annealing process and is kept suspended through the plasma nozzle (5), so that damages or nodulation to the support roller (6) in the heating process can be avoided or relieved; and high-silicon and high-grade electrical steel with high magnetic properties (low iron loss and relatively high grade) and excellent surface quality is obtained.
Description
Technical field
The invention belongs to electrical steel treatment facility technical field, particularly relate to a kind of electrical steel annealing heating method for supporting.
Background technology
The large-scale continuous production of cold rolling high grade electric steel is by improving Si, Al content of steel, reduces the impurity element of steel, reasonable hot rolling and provide continuous annealing (high temperature) and realize.The high grade electric steel trade mark is higher, and iron loss is lower.Iron loss reduces, and cold rolled annealed temperature improves the means that are absolutely necessary.
The annealing of cold rolling non-oriented electrical steel realizes in continuous annealing furnace.The function of continuous annealing furnace can realize under reducing atmosphere, by the existence of water vapour, in steel, carbon forms carbon monoxide, removes the recrystallize that unnecessary carbon and high annealing temperature realize requiring from steel.Realize decarburization and the recrystallize of steel band, the protective atmosphere of the different piece in continuous annealing furnace is different with Heating temperature, and the atmosphere of decarbonized portion is made up of hydrogen, nitrogen and water vapour, and dew point is high, temperature is lower; The protective atmosphere of recrystallize part is made up of hydrogen, nitrogen, and dew point is low, temperature is high, and temperature annealing more than 1000 DEG C wishes to reach.
Realizing in process of the present invention, contriver finds that prior art at least exists following problem:
Electrical steel magnetic property is very responsive to internal stress, and annealing process requires to ensure low internal stress, and the high-temperature part of continuous annealing furnace forbids that steel band causes steel band bending by deflector roll and forms stress for this reason.Namely cold rolling electric continuous annealing all adopts horizontal stove anneal, and in horizontal stove, prior art adopts supporting roll to support steel band.For preventing supporting roll (6) from causing damage to steel strip surface, there is very high requirement to roll surface.Present supporting roll is adopt carbon materials (graphite) or pottery to manufacture roller shell to contact with belt steel surface substantially.Because high-silicon electrical steel annealing needs through too high moisture, hot environment, the surface of steel is oxidized, reduce under high hydrogen atmosphere, hot conditions again, steel surface is very soft, under high temperature and deadweight condition, be very easy to supporting roll (6) surface sticking to carbon materials (graphite) or pottery manufacture, annealed band surface is badly damaged.
Summary of the invention
Technical problem to be solved by this invention is a kind of employing plasma gas floating support electrical steel, avoids or reduce the electrical steel annealing heating method for supporting of annealed band surface damage.
In order to solve the problems of the technologies described above, the technical solution adopted in the present invention is: a kind of electrical steel annealing heating method for supporting, comprises body of heater, have in described body of heater:
The heating zone that steel band is annealed and soaking zone;
At the supporting roll of body of heater inner support steel band;
To steel band ejection gas, the plasma nozzle supporting steel band;
Annealing heating process comprises the steps:
1) be heated to annealing temperature between steel band heating zone in the lehr and soaking zone and be incubated;
2) after, steel band enters the cooling section of body of heater, cool to room temperature;
3) in strip anneal process, plasma nozzle, to steel band blowing gas, makes the steel band of annealing portion depart from the support of supporting roll, is separated and suspends with supporting roll.
Described heating zone and equal hot junction separate by arranging partition wall.
Described supporting roll is uniformly distributed in body of heater.
Described plasma nozzle has two, is separately positioned on heating zone and soaking zone.
Described supporting roll has two, lays respectively at heating zone and body of heater outlet.
Described plasma nozzle has two, between the soaking zone, two supporting rolls of body of heater.
In the 3rd step, in plasma nozzle, pass into gas, gas heats up in plasma nozzle, volume expands, and the plasma body of expansion, from the ejection of higher ion nozzle, sprays to the below of the steel band needing annealing, form an air cushion, hold steel band, make steel band be separated with supporting roll and suspend.
A technical scheme tool in technique scheme has the following advantages or beneficial effect, utilize neutral character and the high-temperature volume expansion of plasma body, rely on the Bernoulli effect of high temperature fluid, make the steel band in annealing process, can support not having roller-way or steel band be reduced the pressure of roller-way due to the support of gas, decrease supporting roll high temperature, the loss of high humidity and dross, steel band can be annealed at the temperature higher than usual steel band.
Under same quality coil of strip metallurgical quality condition, can improve annealing high, the iron loss of electrical steel is reduced.
1), under same quality coil of strip metallurgical quality condition, the electrical steel of the higher trade mark (iron loss is lower) can be obtained;
2) due to the suspension of steel band, avoid or alleviate to the damage of supporting roll or dross in heat-processed, obtaining high magnetic characteristics (low iron loss, the trade mark are higher) and the high silicon of excellent surface quality, high grade electric steel.
Accompanying drawing explanation
The structural representation of electrical steel annealing heating bracing or strutting arrangement of Fig. 1 for providing in the embodiment of the present invention one;
The structural representation of electrical steel annealing heating bracing or strutting arrangement of Fig. 2 for providing in the embodiment of the present invention two;
Fig. 3 is the first embodiment structural representation of the plasma nozzle of Fig. 1;
Fig. 4 is the second embodiment structural representation of the plasma nozzle of Fig. 1;
Fig. 5 is the third embodiment structural representation of the plasma nozzle of Fig. 1;
Mark in above-mentioned figure is: 1, steel band, and 2, body of heater, 3, heating zone, 4, soaking zone, 5, plasma nozzle, 6, supporting roll, 7, partition wall.
Embodiment
For making the object, technical solutions and advantages of the present invention clearly, below in conjunction with accompanying drawing, embodiment of the present invention is described further in detail.
Embodiment one
See Fig. 1, be heated to annealing temperature between the heating zone 3 of cold-rolled steel strip in silicon steel continuous annealing furnace and soaking zone 4 and held for some time enters cooling section subsequently, to room temperature after cooling.The length of steel band in horizontal annealing furnace is very long, entrance and exit supporting roll 6 fixing under, the steel band of horizontality is because the effect of gravity is by sagging.Distance, the tension force of sag of chain and two resting points are relevant with weight.With plasma body winding-up levitation device as support, reduce the overhang of band steel.The quantity of plasma body winding-up levitation device produces the flow of gas according to furnace superintendent, plasma body winding-up levitation device, the sag of chain of pressure and requirement is arranged.
The oxidation that the mixture of hydrogen and nitrogen prevents steel band when high temperature as protective atmosphere is adopted in cold rolled silicon steel annealing furnace.If steel band needs decarburization, containing a small amount of water (steam) in gas mixture.The general > of furnace temperature 800 DEG C.In order to be increased in the reduction of soaking zone 4, partition wall 7 being set between heating zone 3 and soaking zone 4, reducing the gas of heating zone 3 and the convection current of soaking zone 4 shielding gas.
Hydrogen or nitrogen or argon gas, be first preheating to certain temperature by the waste gas of annealing furnace, then pass into plasma nozzle 5.High-temperature plasma is raised to > more than 950 DEG C from room temperature, there is huge expansion in volume, the plasma body (neutrality) of expansion sprays from plasma nozzle 5, sprays to the below of the steel band needing annealing, form an air cushion, hold due to steel band gravity cause sagging.In the lehr, in shielding gas, contactless object completes annealing to such steel band.
Because steel band is annealed under without the condition of object contact, annealing temperature is high, and the electrical steel iron loss after annealing is low, and performance is high, and surface quality is high.
Because steel band is annealed under without the condition of object contact, avoid supporting roll 6 when envrionment temperature height, the high temperature oxidation caused, wear damage.Without supporting roll 6, avoid, due to supporting roll 6 surface deterioration, causing steel strip surface quality significantly to decline.
Embodiment two
See Fig. 2, be heated to annealing temperature between the heating zone 3 of cold-rolled steel strip in silicon steel continuous annealing furnace and soaking zone 4 and held for some time enters cooling section subsequently, to room temperature after cooling.The length of steel band in horizontal annealing furnace is very long, has installed supporting roll 6 in entrance, centre and outlet, and between supporting roll 6, the steel band of horizontality is because the effect of gravity is by sagging.Simultaneously steel band weight be steel band sagging while, form certain pressure to supporting roll 6.To the size of supporting roll 6 pressure, relevant with the distance between thickness of strips, supporting roll 6, tension force.With plasma body winding-up levitation device as supplemental support, reduce the overhang of band steel, reduce pressure to supporting roll 6.Plasma body winding-up levitation device is arranged between two supporting rolls 6.
The oxidation that the mixture of hydrogen and nitrogen prevents steel band when high temperature as protective atmosphere is adopted in cold rolled silicon steel annealing furnace.If steel band needs decarburization, containing a small amount of water (steam) in gas mixture.The general > of furnace temperature 800 DEG C.In order to be increased in the reduction of soaking zone 4, partition wall 7 being set between heating zone 3 and soaking zone 4, reducing the gas of heating zone 3 and the convection current of soaking zone 4 shielding gas.
Hydrogen or nitrogen or argon gas, be first preheating to certain temperature by the waste gas of annealing furnace, then pass into plasma nozzle 5.High-temperature plasma is raised to > more than 950 DEG C from room temperature, there is huge expansion in volume, the plasma body (neutrality) of expansion sprays from plasma nozzle 5, sprays to the below of the steel band needing annealing, form an air cushion, hold due to steel band gravity cause sagging.In the lehr, in shielding gas, contactless object completes annealing to such steel band.
Because steel band is annealed under without the condition of object contact, annealing temperature is high, and the electrical steel iron loss after annealing is low, and performance is high, and surface quality is high.
Because steel band is annealed under without the condition of object contact, avoid supporting roll 6 when envrionment temperature height, the high temperature oxidation caused, wear damage.Without supporting roll 6, avoid, due to supporting roll 6 surface deterioration, causing steel strip surface quality significantly to decline.
As shown in Figure 3, be the first embodiment structural representation of plasma nozzle 5, comprise supporting seat and electrode bar;
Supporting seat is fixedly connected with drop-bottom and insulate with drop-bottom, is provided with cavity in supporting seat;
Electrode bar stretches in the cavity of supporting seat;
Supporting seat upper surface is provided with can for the outlet of gas ejection in supporting seat cavity, and the upper surface of supporting seat is the bearing surface of electrical steel; Supporting seat lower end is provided with and supplied gas can enters the import of cavity in stove;
Power supply is by circuit connection electrode rod and supporting seat, and the supporting seat part be connected with circuit is conductive material.
Supporting seat is formed by connecting by the seat of honour and lower seat, and the seat of honour is electro-conductive material, and lower seat is insulating material.
Be provided with upper cavity in the seat of honour, in lower seat, be provided with lower chamber; Upper cavity is semisphere; Import is arranged on lower seat, and outlet is arranged on the seat of honour.
Electrode bar upper end is ball-type and stretches in upper cavity.
What in stove, enter cavity by import is shielding gas in stove, is hydrogen/nitrogen.
The seat of honour and lower seat are cylindrical.
Current conducting rod stretches in stove from stove, power supply be positioned at stove outer and with electrode bar stove outward part be connected; The seat of honour is provided with current conducting rod, and power supply is connected with current conducting rod by circuit.
By arranging an electric heating chamber.In electric heating chamber, by gaseous media under the heating of strong current, gas temperature improves, and forms plasma flow.At this moment expand under plasma gas volume ratio room temperature doubly a lot, the gas after volumetric expansion is ejected into operating steel band by outlet, is formed and supports steel band.
As shown in Figure 4, be the second embodiment structural representation of plasma nozzle 5, have:
Air-flow slowing device, it is connected on the drop-bottom in stove, and the upper surface of air-flow slowing device is provided with pneumatic outlet, and upper surface is as the bearing surface of electrical steel;
Plasma cabinet, its inside has cavity, and plasma is provided with the opening be communicated with cavity cashier's office in a shop, and opening is communicated with air-flow slowing device;
Electrode bar, it stretches in the cavity of plasma cabinet;
Electric supply installation, comprises power supply, and power supply is by circuit connection electrode rod and plasma cabinet, and plasma cabinet is conductive material, and electrode bar and plasma cabinet form discharge electrode;
Diffuser, it passes into gas by pipeline in the cavity of plasma cabinet.
Air-flow slowing device is nozzle, and the diameter of the shower nozzle of nozzle is greater than the air inlet diameter of nozzle.
As shown in Figure 5, be the third embodiment structural representation of plasma nozzle 5, air-flow slowing device is Venturi tube, and the upper surface of Venturi tube is provided with venting port, and upper surface is as the bearing surface of electrical steel.
The necking part of Venturi tube is provided with and the air inlet port be communicated with in stove.
The cavity top of plasma body is semisphere; Electrode bar upper end is ball-type.
The gas passed in the cavity of plasma body cabinet is hydrogen/nitrogen/argon gas.
Plasma body is cylindrical.
Plasma body one end is open, and is provided with base plate and closes open end; Base plate is isolation material, and electrode bar stretches in the cavity of plasma body cabinet through base plate.
After adopting above-mentioned scheme, by arranging an electric heating chamber.In electric heating chamber, by gaseous media under the heating of strong current, gas temperature improves, and forms plasma flow.At this moment expand under plasma gas volume ratio room temperature doubly a lot, the gas after volumetric expansion is ejected into operating steel band by plasma body cabinet and gas slowing device, is formed and supports steel band.
Utilize neutral character and the high-temperature volume expansion of plasma body, rely on the Bernoulli effect of high temperature fluid, make the steel band in annealing process, can support not having roller-way or steel band be reduced the pressure of roller-way due to the support of gas, decrease supporting roll 6 high temperature, the loss of high humidity and dross, steel band can be annealed at the temperature higher than usual steel band.
Under same quality coil of strip metallurgical quality condition, can improve annealing high, the iron loss of electrical steel is reduced.
Under 1 same quality coil of strip metallurgical quality condition, the electrical steel that higher trade mark iron loss is lower can be obtained;
2, due to the suspension of steel band, avoid or alleviate to the damage of supporting roll 6 or dross in heat-processed, obtain the low iron loss of high magnetic characteristics, the trade mark higher and the high silicon of excellent surface quality, high grade electric steel.
Above by reference to the accompanying drawings to invention has been exemplary description; obvious specific implementation of the present invention is not subject to the restrictions described above; as long as have employed the improvement of the various unsubstantialities that method of the present invention is conceived and technical scheme is carried out; or design of the present invention and technical scheme directly applied to other occasion, all within protection scope of the present invention without to improve.
Claims (7)
1. an electrical steel annealing heating method for supporting, comprises body of heater (2), it is characterized in that, described body of heater has in (2):
The heating zone (3) that steel band is annealed and soaking zone (4);
At the supporting roll (6) of body of heater (2) inner support steel band;
To steel band ejection gas, the plasma nozzle (5) supporting steel band;
Annealing heating process comprises the steps:
1) be heated to annealing temperature between steel band heating zone in the lehr (3) and soaking zone (4) and be incubated;
2) after, steel band enters the cooling section of body of heater (2), cool to room temperature;
3) in strip anneal process, plasma nozzle (5), to steel band blowing gas, makes the steel band of annealing portion depart from the support of supporting roll (6), is separated with supporting roll (6) and suspends.
2. electrical steel annealing heating method for supporting as claimed in claim 1, it is characterized in that, described heating zone (3) and equal hot junction separate by arranging partition wall (7).
3. electrical steel annealing heating method for supporting as claimed in claim 1, it is characterized in that, described supporting roll (6) is uniformly distributed in body of heater (2).
4. electrical steel annealing heating method for supporting as claimed in claim 3, it is characterized in that, described plasma nozzle (5) has two, is separately positioned on heating zone (3) and soaking zone (4).
5. electrical steel annealing heating method for supporting as claimed in claim 1, it is characterized in that, described supporting roll (6) has two, lays respectively at heating zone (3) and body of heater (2) outlet.
6. electrical steel annealing heating method for supporting as claimed in claim 5, it is characterized in that, described plasma nozzle (5) has two, is positioned between the soaking zone (4) of body of heater (2), two supporting rolls (6).
7. electrical steel annealing heating method for supporting as claimed in claim 1, it is characterized in that, in the 3rd step, in plasma nozzle (5), pass into gas, gas heats up in plasma nozzle (5), volume expands, the plasma body expanded, from higher ion nozzle (5) ejection, sprays to the below of the steel band needing annealing, forms an air cushion, hold steel band, make steel band be separated with supporting roll (6) and suspend.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510270536.XA CN104831053B (en) | 2015-05-25 | 2015-05-25 | A kind of electrical sheet annealing heating method for supporting |
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| CN201510270536.XA CN104831053B (en) | 2015-05-25 | 2015-05-25 | A kind of electrical sheet annealing heating method for supporting |
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| CN105039675A (en) * | 2015-08-27 | 2015-11-11 | 苏州中门子科技有限公司 | Air cushion furnace with V-shaped roller supporting device and application of air cushion furnace |
| CN116550822A (en) * | 2023-05-12 | 2023-08-08 | 山东力军建设工程有限公司 | Hollow steel pipe bending mechanism |
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| CN1309758A (en) * | 1998-06-18 | 2001-08-22 | 罗斯空气设备公司 | Convertible apparatus for heat treating materials |
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| CN105039675A (en) * | 2015-08-27 | 2015-11-11 | 苏州中门子科技有限公司 | Air cushion furnace with V-shaped roller supporting device and application of air cushion furnace |
| CN116550822A (en) * | 2023-05-12 | 2023-08-08 | 山东力军建设工程有限公司 | Hollow steel pipe bending mechanism |
| CN116550822B (en) * | 2023-05-12 | 2023-09-26 | 山东力军建设工程有限公司 | Hollow steel pipe bending mechanism |
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