Method for on-line roller grinding in an annealing furnace

Abstract

The embodiment of the application provides an annealing furnace in-line roller grinding method, relates to the technical field of cold-rolled strip production, and the method comprises the following steps: positioning a furnace roller station number which needs to be ground, and determining a current furnace roller working condition which needs to be ground; determining a roller grinding process according to the furnace roller working condition which needs to be ground; adopting the corresponding roller grinding process to grind the roller, and determining whether the roller grinding process needs to be adjusted according to the defect morphology change of the strip steel running on the furnace roller after the roller is ground. The method can quickly and accurately position the furnace roller which needs to be ground, and by modifying the diameter of the furnace roller, a speed difference between the strip steel and the furnace roller is generated, and then the effect of 'roller grinding strip' or'strip grinding roller' is generated, so that the on-line roller grinding without stopping is finally realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cold-rolled strip production, in particular to an online roller grinding method in an annealing furnace. BACKGROUND

[0002] At present, the cold-rolled strip production lines built in China basically include continuous annealing lines, and the continuous annealing furnace is one of the most important equipment in the continuous annealing line, which mainly functions to reduce the internal stress of the cold-rolled strip and eliminate work hardening.

[0003] The annealing furnace is equipped with hundreds of furnace rollers, and the quality of the surface of the furnace rollers directly affects the yield of the strip. Due to the poor working conditions of the furnace rollers, they are long-term served at a temperature above 700 DEG C, and due to the reasons such as unclean cleaning of the strip, slip of the strip, high dew point in the furnace and production of high-strength steel, the surface of the furnace rollers is nubbly, and then periodic pitting or indentation is formed on the surface of the strip, which seriously affects the surface quality of the strip.

[0004] Once the surface of the furnace roller is nubbly during production, it needs to be treated immediately, thereby reducing the quality loss of the product. The method for removing the nubbly surface of the furnace roller is generally to stop the furnace for grinding or replace the furnace roller, but stopping the furnace consumes a long time and affects the production efficiency, and the process of stopping the furnace for temperature rising and falling will inevitably cause energy waste. SUMMARY

[0005] Embodiments of the present application provide an online roller grinding method in an annealing furnace to solve the technical problems such as the need to stop the furnace for grinding the furnace roller in the prior art.

[0006] Other characteristics and advantages of the present application will become apparent from the following detailed description, or will be learned by practice of the present application.

[0007] According to a first aspect of the embodiments of the present application, an online roller grinding method in an annealing furnace is provided, comprising:

[0008] Positioning the furnace roller station number which needs to be ground, and determining the furnace roller working condition which needs to be ground at present;

[0009] Determining the roller grinding process according to the furnace roller working condition which needs to be ground;

[0010] Grinding the roller by using the corresponding roller grinding process, and determining whether to adjust the roller grinding process according to the defect morphology change of the strip running on the furnace roller after grinding.

[0011] In some embodiments of the present application, based on the foregoing scheme, the positioning of the furnace roller station number which needs to be ground comprises:

[0012] Partitioning the furnace rollers in the annealing furnace;

[0013] determine the target area where the furnace roller to be ground is located on the furnace roller layout based on the furnace roller diameter to be ground;

[0014] In the target area, the strip on the furnace roller is corrected to determine the furnace roller position number to be ground.

[0015] In some embodiments of the present application, based on the foregoing scheme, the furnace roller in the annealing furnace is divided into:

[0016] According to the position of the furnace roller in the annealing furnace, all the furnace rollers are divided into preheating zone, first heating zone, second heating zone, third heating zone, soaking zone, slow cooling zone, rapid cooling zone, first aging zone, second aging zone, third aging zone, final cooling zone and water quenching zone.

[0017] In some embodiments of the present application, based on the foregoing scheme, the determination of the furnace roller diameter to be ground includes:

[0018] The single period interval of the periodic indentation on the strip is measured, and the furnace roller diameter to be ground is determined according to formula (1);

[0019] L=πD; (1)

[0020] In formula (1), L represents the single period interval of the indentation; π represents the circular constant; D represents the diameter of the furnace roller.

[0021] In some embodiments of the present application, based on the foregoing scheme, the correction of the strip on the furnace roller in the target area to determine the furnace roller position number to be ground includes:

[0022] The strip running on each furnace roller in the target area is corrected by using the correction furnace roller;

[0023] During the correction process, the change of the indentation on the strip surface is observed;

[0024] According to the change, the furnace roller position number to be ground is determined.

[0025] In some embodiments of the present application, based on the foregoing scheme, the determination of the furnace roller position number to be ground according to the change includes:

[0026] Observe whether the indentation on the strip surface changes in the transverse direction;

[0027] If the change occurs, the correction furnace roller currently used for correction is determined;

[0028] The next group of furnace rollers of the current correction furnace roller is taken as the target group, and the furnace roller position number to be ground in the target group is determined in combination with the indentation morphology.

[0029] In some embodiments of the present application, based on the foregoing scheme, the correction amount is 30-50 mm during the correction process.

[0030] In some embodiments of the present application, based on the foregoing scheme, the determination of the grinding roller process comprises:

[0031] determination of the grinding roller mode;

[0032] selection of the grinding roller strip steel;

[0033] and determination of various control parameters in the annealing furnace.

[0034] In some embodiments of the present application, based on the foregoing scheme, the grinding roller using the corresponding grinding roller process comprises:

[0035] adjusting the diameter of the furnace roller that needs to be ground to generate a speed difference between the furnace roller and the grinding roller strip steel to grind the furnace roller.

[0036] In some embodiments of the present application, based on the foregoing scheme, the grinding roller strip steel is selected as CQ grade aluminum killed steel.

[0037] The technical scheme of the present application can quickly and accurately locate the furnace roller that needs to be ground, and by modifying the diameter of the furnace roller, a speed difference is generated between the strip steel and the furnace roller, thereby generating the effect of “roller grinding strip” or “strip grinding roller”, and finally realizing online grinding without stopping.

[0038] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0039] The drawings herein are incorporated into the specification and form part of the specification, show embodiments consistent with the present application, and together with the specification serve to explain the principles of the present application. It is obvious that the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings from these drawings without creative labor. In the drawings:

[0040] Figure 1 shows a flowchart of an online grinding method in an annealing furnace according to an embodiment of the present application;

[0041] Figure 2 shows a detailed flowchart of the positioning of the furnace roller station number that needs to be ground according to an embodiment of the present application;

[0042] Figure 3 shows a detailed flowchart of step S1300 according to an embodiment of the present application;

[0043] Figure 4 A detailed flowchart illustrating step S1330 according to one embodiment of the present application is shown. DETAILED DESCRIPTION

[0044] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations may, however, be implemented in many different forms and should not be construed as limited to the implementations set forth herein; rather, these implementations are provided so that this disclosure will be thorough and complete, and will fully convey the inventive aspects to those skilled in the art. Like reference numerals may refer to like elements throughout.

[0045] Moreover, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the application. One skilled in the relevant art will recognize, however, that the

[0046] The flowcharts shown in the figures should not be deemed to be exhaustive and should not be construed as including all of the details and operations / steps, nor should they be construed as necessarily being executed in the order described. For example, some operations / steps can be further broken down, and some operations / steps can be combined or partially combined, so the actual execution order can be changed according to actual conditions.

[0047] It should be noted that the terms "first", "second", and the like in the description and in the claims of the present application and the above-described figures are used to distinguish similar objects and are not necessarily used to describe a particular sequential or chronological order. It should be understood that the objects thus designated can be interchanged, where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described.

[0048] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0049] Some embodiments of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments and features in the embodiments can be combined with each other without conflict.

[0050] Reference is made to Figure 1Fig. 1 shows a schematic diagram of an on-line roller grinding method in an annealing furnace according to an embodiment of the present application.

[0051] As shown in Fig. 1, an on-line roller grinding method in an annealing furnace is shown, which specifically comprises steps S1000-S3000. Figure 1

[0052] Step S1000, position the specific roller station number that needs to be ground, and determine the working condition of the roller that needs to be ground at present.

[0053] It can be understood that after the position of the roller that needs to be ground is determined, the working condition of the roller can be confirmed by observing the roller carefully, and the problems of the roller can be found out.

[0054] In some possible embodiments, as shown in Fig. 2, the positioning of the specific roller station number that needs to be ground specifically comprises steps S1100-S1300. Figure 2

[0055] Step S1100, divide the rollers in the annealing furnace into different zones.

[0056] All the rollers in the annealing furnace are divided into different zones, and then the roller that needs to be ground is found in different zones, which greatly improves the searching efficiency.

[0057] Step S1200, determine the diameter of the roller that needs to be ground, and determine the target zone where the roller that needs to be ground is located on the roller layout diagram based on the diameter of the roller.

[0058] It should be noted that the rollers in the annealing furnace are of different sizes and diameters, and the rollers in the same diameter section are arranged together, so after the diameter of the roller that needs to be ground is confirmed, the target zone where the roller is located can be determined by using the roller layout diagram.

[0059] It can be understood that the roller layout diagram refers to a schematic diagram of the specific arrangement of each roller in the annealing furnace, and the overall distribution of the rollers in the annealing furnace can be seen by referring to the roller layout diagram.

[0060] It can be understood that the target zone in the present embodiment refers to the zone where the roller that needs to be ground is located.

[0061] Step S1300, in the target zone, the strip on the roller is subjected to deviation correction treatment to determine the roller station number that needs to be ground.

[0062] ​​It can be understood that the deviation correction treatment described in the embodiment refers to measures or means used to correct the running deviation of the strip steel. In the annealing furnace, the strip steel runs on the furnace roller, and the furnace roller has a great influence on the running of the strip steel. When the furnace roller has a problem, the strip steel will deviate. Therefore, by correcting the strip steel, the problem furnace roller can be found.

[0063] In some possible embodiments, the step S1100 specifically includes:

[0064] According to the position of the furnace roller inside the annealing furnace, all the furnace rollers are divided into zones, specifically into a preheating zone, a first heating zone, a second heating zone, a third heating zone, a soaking zone, a slow cooling zone, a fast cooling zone, a first aging zone, a second aging zone, a third aging zone, a final cooling zone, and a water quenching zone.

[0065] It should be noted that the entire inside of the annealing furnace is divided into a preheating section, a heating 1 section, a heating 2 section, a heating 3 section, a soaking section, a slow cooling section, a fast cooling section, an aging 1 section, an aging 2 section, an aging 3 section, a final cooling section, and a water quenching section. By confirming the position of each furnace roller inside the annealing furnace, the zoning of all the furnace rollers can be achieved. For example, the furnace rollers in the preheating section are divided into the preheating zone, and the furnace rollers in the heating 1 section are divided into the first heating zone.

[0066] In some possible embodiments, the determination of the diameter of the furnace roller that needs to be ground includes:

[0067] The single period interval of the periodic indentation on the strip steel is measured, and the diameter of the furnace roller that needs to be ground is determined according to formula (1);

[0068] L = πD; (1)

[0069] In formula (1), L represents the single period interval of the indentation; π represents the circular constant; and D represents the diameter of the furnace roller.

[0070] It should be noted that the indentation refers to a trace exhibited when the strip steel surface is damaged by the furnace roller due to problems such as nodulation of the furnace roller when the strip steel runs on the furnace roller. The indentation appears periodically along the length direction of the strip steel (i.e., the running direction of the strip steel) and coincides with the circumference of the furnace roller.

[0071] In some possible embodiments, as shown in FIG. 13, Figure 3 the step S1300 specifically includes steps S1310 to S1330.

[0072] In step S1310, the deviation correction treatment is performed on the strip steel running on each furnace roller in the target zone by using the deviation correction furnace roller.

[0073] It should be noted that in the present embodiment, the deviation rectifying furnace roller refers to a furnace roller for rectifying the deviation of the strip steel, which can move in the transverse direction (perpendicular to the length direction of the strip steel); in the annealing furnace, the deviation rectifying furnace rollers are arranged in groups at a fixed interval.

[0074] In the deviation rectifying process, the deviation rectifying amount is 30-50mm, and the running speed of the strip steel is 120-180mpm.

[0075] In step S1320, the change of the indentation on the surface of the strip steel is observed during the deviation rectifying process.

[0076] In step S1330, the furnace roller position number that needs to be ground is determined according to the change.

[0077] It can be understood that if the strip steel does not deviate during running, the position of the indentation on the strip steel will not change, and it should still appear as a straight line parallel to the length direction of the strip steel. When the strip steel deviates, the position of the subsequent indentation will change, and will not be on the same horizontal straight line as the previous indentation. Therefore, when the strip steel is rectified, the position of the indentation on the strip steel will change accordingly, and the position of the furnace roller that has a problem can be determined from the changed position.

[0078] In some possible embodiments, as shown in FIG. 13B, the step S1330 specifically includes steps S1331-S1333. Figure 4

[0079] In step S1331, whether the indentation on the surface of the strip steel changes in the transverse direction is observed.

[0080] It can be understood that the transverse direction refers to the direction perpendicular to the length direction (running direction) of the strip steel.

[0081] In step S1332, if the change occurs, the deviation rectifying furnace roller currently used for the deviation rectifying process is determined.

[0082] In step S1333, the next group of furnace rollers of the current deviation rectifying furnace roller is taken as the target group, and the position number of the furnace roller that needs to be ground in the target group is determined according to the appearance of the indentation.

[0083] It can be understood that the furnace rollers in the annealing furnace are distributed in groups, and the number of furnace rollers in each group is between 3-10. When the indentation on the surface of the strip steel passing through the current deviation rectifying furnace roller moves in the transverse direction, it indicates that there is a furnace roller that needs to be ground in the group of furnace rollers that the strip steel has just passed through. After the target group is determined, since the number of furnace rollers in the target group is not large, the furnace roller that needs to be ground can be easily found in the target group according to the appearance of the indentation.

[0084] It should be noted that in the present embodiment, the running direction of the strip steel is taken as the front, and the opposite direction is taken as the back.​

[0085] For example, the furnace rollers in the annealing furnace and the correction furnace rollers are arranged in the running direction of the strip steel as {1, 2, 3}, a, {4, 5, 6}, b, {7, 8, 9}, wherein {1, 2, 3}, {4, 5, 6}, {7, 8, 9} are furnace roller groups, and a and b are correction furnace rollers. Then {1, 2, 3} is the next group of furnace rollers of a, and {4, 5, 6} is the next group of furnace rollers of b. If the correction furnace roller a is used for correction, the position of the indentation on the strip steel changes at this time, and then the furnace roller group {1, 2, 3} is the target group. The indentation morphology can be used to find the furnace roller that needs to be ground in the furnace roller group {1, 2, 3}.

[0086] Continuing to refer to Figure 1 , in step S2000, the grinding roller process is determined according to the working condition of the furnace roller that needs to be ground.

[0087] In some possible embodiments, the determination of the grinding roller process includes:

[0088] The grinding roller mode is determined, the grinding roller strip steel is selected, and various control parameters in the annealing furnace are determined.

[0089] It should be noted that in the present embodiment, the grinding is performed by grinding the furnace roller with the strip steel. Since the strip steel generates friction when running on the furnace roller, the friction between the two can be used to grind the furnace roller. Since the grinding is achieved by using the running of the strip steel, various control parameters in the annealing furnace during the grinding process need to be determined, such as setting the atmosphere in the furnace to nitrogen-hydrogen protective gas, the hydrogen volume fraction is 5-8%, the running speed of the strip steel is set to 120-180 mpm, the furnace temperature is set to 500-600℃, the positive pressure in the furnace is set to 1.1-1.2 hpa, etc.; and setting the furnace temperature to 500-600℃ can make the nodules on the furnace roller shrink, thereby reducing the adhesion between the nodules and the furnace roller, and setting the positive pressure in the furnace to 1.1-1.2 hpa can make the nodules easy to diffuse during the grinding process, thereby achieving the purpose of precise grinding without opening the furnace.

[0090] In some possible embodiments, the grinding roller strip steel is CQ grade aluminum killed steel.

[0091] Killed steel refers to completely deoxidized steel, that is, the mass fraction of oxygen is not more than 0.01% (generally 0.002%-0.003%); the shrinkage rate of killed steel is low, but the organization is compact, the segregation is small, the quality is uniform, and it is very suitable for grinding furnace rollers.

[0092] Continuing to refer to Figure 1 , in step S3000, the grinding is performed by using the corresponding grinding roller process, and whether the grinding roller process needs to be adjusted is determined according to the defect morphology change of the strip steel running on the furnace roller after the grinding.

[0093] It can be understood that since the strip steel is used to grind the furnace roller in the embodiment, the grinding may not be in place, resulting in the existence of nodulation on the furnace roller, so it is needed to determine whether the grinding process needs to be adjusted and the furnace roller needs to be ground again according to the defect morphology change of the surface of the strip steel.

[0094] In some possible embodiments, the grinding of the furnace roller by using the corresponding grinding process comprises:

[0095] The diameter of the furnace roller that needs to be ground is adjusted to generate a speed difference between the furnace roller and the grinding strip steel, so as to grind the furnace roller.

[0096] It can be understood that when the speed difference exists between the furnace roller and the grinding strip steel, the friction between the two will be correspondingly increased, and the grinding of the furnace roller can be realized by using the increased friction.

[0097] Specifically, in the embodiment, the modified amount of the diameter of the furnace roller is ±6-8% of the original diameter, so as to ensure that the friction is in a suitable state.

[0098] Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. Variations and modifications of the embodiments disclosed herein can be made based on the description set forth herein, without departing from the scope and spirit of the application. The application is intended to cover any variations, uses or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure as come within the known and customary practice within the art to which the application pertains. It is to be understood that the application is not limited to the specific products, methods, or the exact details of construction described above and illustrated in the accompanying drawings, but that the application is at least entitled to protection within the full scope of the disclosure and any equivalents thereof. The scope of the application is limited only by the claims that follow.

Claims

1. An in-line roller grinding method in an annealing furnace, characterized by, The application relates to an annealing furnace roller grinding method. The method comprises the following steps: locating a specific roller station number that needs to be ground and determining a current roller working condition that needs to be ground; determining a roller grinding process according to the roller working condition that needs to be ground; adopting the corresponding roller grinding process to grind the roller and determining whether to adjust the roller grinding process according to the defect morphology change of the strip steel running on the roller after the roller is ground; the method for locating the specific roller station number that needs to be ground comprises the following steps: dividing the rollers in the annealing furnace into zones; determining the roller diameter that needs to be ground and determining the target zone where the roller that needs to be ground is located on the roller layout map based on the roller diameter; performing deviation correction treatment on the strip steel on the roller in the target zone to determine the roller station number that needs to be ground; the method for performing deviation correction treatment on the strip steel on the roller in the target zone to determine the roller station number that needs to be ground comprises the following steps: performing deviation correction treatment on the strip steel running on each roller in the target zone by using a deviation correction roller; observing the change of the indentation on the surface of the strip steel during the deviation correction treatment; determining the roller station number that needs to be ground according to the change; the method for determining the roller station number that needs to be ground according to the change comprises the following steps: observing whether the indentation on the surface of the strip steel changes in the transverse direction; if the indentation changes, determining the deviation correction roller currently used for the deviation correction treatment; 2. The method of claim 1, wherein, taking the next group of rollers of the current deviation correction roller as a target group and determining the roller station number that needs to be ground in the target group in combination with the indentation morphology. the method for dividing the rollers in the annealing furnace into zones comprises the following steps:

3. The method of claim 1, wherein, dividing all the rollers into zones according to the positions of the rollers in the annealing furnace, and specifically dividing the rollers into a preheating zone, a first heating zone, a second heating zone, a third heating zone, a soaking zone, a slow cooling zone, a fast cooling zone, a first aging zone, a second aging zone, a third aging zone, a final cooling zone and a water quenching zone. the method for determining the roller diameter that needs to be ground comprises the following steps: ； （1） In equation (1), denotes the individual periodicity of the indentations; denotes the ratio of the circumference to the diameter; denotes the roll diameter.

4. The method of claim 1, wherein, measuring the single period interval of the periodic indentation on the strip steel and determining the roller diameter that needs to be ground according to formula (1); 5. The method of claim 1, wherein, during the deviation correction treatment, the deviation correction amount is 30-50 mm. the method for determining the roller grinding process comprises the following steps: determining a roller grinding mode; selecting a roller grinding strip steel; and 6. The method of claim 5, wherein, determining various control parameters in the annealing furnace. the method for grinding the roller by adopting the corresponding roller grinding process comprises the following steps:

7. The method of claim 6, wherein, adjusting the roller diameter that needs to be ground to generate a speed difference between the roller and the roller grinding strip steel to grind the roller. the roller grinding strip steel is CQ grade aluminum killed steel.

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