CN111621636B - A continuous annealing furnace furnace roll - Google Patents

Abstract

The invention discloses a furnace roll of a continuous annealing furnace, which is set as a double-tapered roll. The double-tapered roll comprises: a straight section located in the middle, and a first tapered section arranged adjacent to both sides of the straight section in the axial direction; and a second taper segment arranged next to each first taper segment, wherein the taper of the second taper segment is different from that of the first taper segment; wherein there is a first transition arc between the straight segment and the first taper segment, and the first taper segment is There is a second transition arc between the segment and the second tapered segment. The continuous annealing furnace roll can overcome the defects in the prior art through the structural design of the double taper, avoid the occurrence of transverse scratches in the production process of the strip, and improve the production efficiency of the strip and the obtained strip products. quality.

Description

A continuous annealing furnace furnace roll

technical field

The invention relates to a furnace roll, in particular to a furnace roll of an annealing furnace.

Background technique

Continuous annealing line is an important part of cold-rolled strip production. It has the advantages of short process, high output and good product quality. It is an indispensable annealing heat treatment equipment for strip production with thin thickness and high surface quality requirements.

In a large vertical furnace, in order to increase the output, the strip needs to run quickly. In order to reduce the deviation of the strip, the roll surface of the furnace roll in the heating section is generally designed as a double-taper roll type with high middle and low ends to generate centripetal force. Make the strip self-correction. However, the strip steel is very soft in high temperature environment. When the strip steel passes through the plate, if deviation occurs, under the action of the crown effect of the furnace roll itself, a self-correcting effect will occur, which will cause the strip steel to be on the surface of the furnace roll. During the lateral slip process, lateral contusion will occur at the position of the furnace roll boss, which will seriously affect the surface quality of the strip.

The above-mentioned problems are particularly obvious when producing automotive panels. However, the current prior art can only reduce the incidence of lateral scratches by reducing the speed of production.

Based on this, it is desirable to obtain a continuous annealing furnace roll, which can overcome the deficiencies of the prior art, is less likely to produce embossing, and solves the problem of prone to lateral contusion in the prior art.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a continuous annealing furnace roll, the continuous annealing furnace roll can overcome the defects in the prior art through the structural design of the double taper, and avoid the occurrence rate of transverse scratches in the production process of the strip steel. , to improve the production efficiency of the strip and the quality of the strip products obtained.

In order to achieve the above object, the present invention proposes a continuous annealing furnace roll, which is set as a double-tapered roll, and the double-tapered roll includes: a straight section located in the middle, and is arranged on both sides of the straight section in the axial direction. The first taper section, and a second taper section disposed next to each first taper section, wherein the second taper section is different from the first taper section; wherein there is a first transition between the straight section and the first taper section A circular arc, with a second transition circular arc between the first tapered segment and the second tapered segment.

In the technical scheme of the present invention, the inventor found through a large number of experimental studies that setting the continuous annealing furnace roll with a first taper section and a second taper section can make it obtain a better plate passing speed and prevent the ladle The first taper section and the second taper section are designed to have two different tapers, which can solve the problem of lateral scratches on the strip in the prior art, and can also avoid indentation on the strip. . The design of the first taper section and the second taper section can be adjusted according to the specific conditions of the implemented embodiment, such as the diameter of the furnace roll, the temperature of the furnace roll and the temperature of the strip, so as to obtain a better through-board. speed, to prevent buckling and deviation.

Further, in the continuous annealing furnace roll of the present invention, the radius r ₁ of the first transition arc and the radius r ₂ of the second transition arc are respectively obtained based on the following models:

r ₁ =2×X ₁ /θ ₁

r ₂ =2×X ₂ /(θ ₁ −θ ₂ )

X ₁ =X ₂ =k×D ₀

Wherein, D ₀ is the diameter of the straight section, and k is a coefficient; θ ₁ and θ ₂ are the taper angle of the first taper segment and the taper angle of the second taper segment, respectively.

Further, in the continuous annealing furnace roll of the present invention, the value of the coefficient k is 0.05-0.07.

This is because: the larger the value of k, the larger the value of X ₁ and X ₂ , the larger the value of r ₁ and r 2 , and the larger the value of X 1 and X 2 , the larger the value of r ₁ and r ₂ , and the larger the value of X ₁ and X ₂ from the perspective of reducing the embossing. The larger the value of ₂ , the more favorable it is, because the radians of r ₁ and r ₂ need to be specially ground with a grinding wheel, so that the roughness of the radian part will be very low after grinding, and the values of X ₁ and X ₂ will increase. However, when the value of k is too large and exceeds 0.7, the remaining length of the straight section will be too short, resulting in that the original roughness can only be kept at a lower percentage of the original step width (for example, the straight section is 300mm, k is 0.725, Then the remaining length of the straight section is only 184mm, and its original roughness can only be 60% of the original step width), which will reduce the frictional force on the surface of the strip furnace roll, which is easy to deviate.

The smaller the k value, the smaller the values of X ₁ and X ₂ , and the smaller the r ₁ and r ₂ , the smaller the influence on the roughness of the roll surface, but the smaller the radian part r ₁ and r ₂ , the convexity will occur. Taiwan print. Based on this, the value range of the coefficient k is preferably limited to 0.05-0.07.

Further, in the continuous annealing furnace roll according to the present invention, the length in the axial direction is 2000-2300 mm.

Further, in the continuous annealing furnace roll of the present invention, the diameter of the straight section is 800-1000 mm.

Further, in the continuous annealing furnace roll of the present invention, the total crown of the continuous annealing furnace roll is set as C, and the total crown C is obtained based on the following model:

C=K ₀ ·(Tr－Ts)×D ₀ /2+C ₀

Wherein, K ₀ is the thermal expansion coefficient of the furnace roll, D ₀ is the diameter of the straight section, Tr is the furnace roll temperature, Ts is the strip temperature, and C ₀ is the reference crown.

Further, in the continuous annealing furnace roll of the present invention, the value of the reference crown C ₀ ranges from 0.1 to 1.5.

Further, in the continuous annealing furnace roll of the present invention, the total crown C is the sum of the crown C1 of the first tapered section and the crown C2 of the second tapered section, wherein C1/C2=1.2 ~1.5.

Further, in the continuous annealing furnace furnace roll of the present invention, the value range of the furnace roll temperature Tr is 920°C to 950°C, and/or the value range of the strip temperature Ts is 780°C to 880°C.

Further, in the continuous annealing furnace roll according to the present invention, the value range of the thermal expansion coefficient is 15×10 ^-6 to 30×10 ^-6 , and the dimension is 1/°C.

Compared with the prior art, the continuous annealing furnace roll of the present invention has the following advantages and beneficial effects:

The continuous annealing furnace furnace roll of the present invention overcomes the defects in the prior art by optimizing the structure of the double taper, and on the one hand, the furnace roll can obtain a better plate passing speed and prevent the occurrence of buckling and deviation problems. On the other hand, by optimizing the taper of the furnace roll boss, the problem of transverse scratches or indentation scratches caused by the furnace rolls in the prior art to the strip steel is solved. Annealing furnace rolls can greatly improve the production efficiency of strip steel and the quality of the obtained strip steel products.

Description of drawings

FIG. 1 is a schematic structural diagram of a continuous annealing furnace roll according to an embodiment of the present invention.

Fig. 2 schematically shows the structure of the first transition arc of the continuous annealing furnace roll in an embodiment of the present invention.

Fig. 3 schematically shows the structure of the second transition arc of the continuous annealing furnace roll in an embodiment of the present invention.

Detailed ways

The continuous annealing furnace roll described in the present invention will be further explained and explained below in conjunction with the accompanying drawings and specific embodiments, but the explanation and explanation do not constitute an improper limitation of the technical solution of the present invention.

1 to 3 schematically illustrate the structure of the continuous annealing furnace roll according to the present invention. Wherein, FIG. 1 is a schematic structural diagram of the continuous annealing furnace roll in one embodiment of the present invention. Fig. 2 schematically shows the structure of the first transition arc of the continuous annealing furnace roll in an embodiment of the present invention. Fig. 3 schematically shows the structure of the second transition arc of the continuous annealing furnace roll in an embodiment of the present invention.

As shown in FIG. 1 , and referring to FIGS. 2 and 3 when necessary, in this embodiment, the continuous annealing furnace rolls are set as double-tapered rolls, wherein the double-tapered roll body has a total length of L, and the double-tapered rolls include The straight section Lc located in the middle, the first tapered section Lt arranged on both sides of the straight section Lc in the axial direction, the first tapered angle is θ ₁ , and the first tapered section Lt arranged next to each first tapered section Lt. Two-tapered segment Le, the second taper angle is θ2, wherein the taper of the second taper segment Le and the first taper segment Lt is different, and there is a first transition arc between the straight segment Lc and the first taper segment Lt, the radius of which is As r ₁ , there is a second transition arc between the first taper segment Lt and the second taper segment Le, the radius of which is r ₂ .

It should be noted that, in FIG. ₁ , D1 is the diameter of the circular section shared by the first tapered section and the _second tapered section, and D2 is the diameter of the circular section of the outermost end face of the second tapered section.

The first transition arc and the second transition arc are the transition area of the boss. If it is not too good, it will cause indentation or lateral scratches to the strip. For this transition area, the radius r of the first transition arc will be used. The radii r ₂ of ₁ and the second transition arc are obtained based on the following models respectively, so as to obtain a better transition arc curve, which can solve the problem of strip quality caused by boss transition:

r ₁ =2×X ₁ /θ ₁

r ₂ =2×X ₂ /(θ ₁ −θ ₂ )

X ₁ =X ₂ =k×D ₀

Wherein, D ₀ is the diameter of the straight section, and k is a coefficient; θ ₁ and θ ₂ are the taper angle of the first taper segment and the taper angle of the second taper segment, respectively. Among them, the value of the coefficient k is 0.05-0.07. The length of the continuous annealing furnace roll in the axial direction (ie, the total length L of the roll body) is 2000-2300 mm. The diameter of the straight section Lc is 800 to 1000 mm.

The total crown C is set according to the diameter of the furnace rolls, the temperature of the furnace rolls and the temperature of the strip steel, so that the strip steel produced by the continuous annealing furnace rolls in this embodiment can obtain a better passing speed and prevent the strip steel from buckling. and deviation.

Based on this, the total convexity C is obtained by the following model:

C=K ₀ ·(Tr－Ts)×D ₀ /2+C ₀

Among them, K ₀ is the thermal expansion coefficient of the furnace roll, D ₀ is the diameter of the straight section, Tr is the furnace roll temperature, Ts is the strip temperature, and C ₀ is the reference crown, wherein, the reference crown C ₀ is taken as The value range is 0.1 to 1.5, the value range of the furnace roll temperature Tr is 920°C to 950°C, and/or the value range of the strip temperature Ts is 780°C to 880°C, and the value range of the thermal expansion coefficient K ₀ is 15. ×10 ^-6 to 30×10 ^-6 , the dimension is 1/°C.

The total convexity C is the sum of the convexity C1 of the first tapered segment and the convexity C2 of the second tapered segment, and C1/C2=1.2˜1.5.

The above-mentioned FIGS. 1 to 3 schematically show the structure of the technical solution. The specific parameters adopted by the L continuous annealing furnace rolls of Examples 1-6 of the present case are listed in Table 1 below.

Table 1.

Table 2 lists the effects on r ₁ , r ₂ and the final strip production effect when k takes different values.

Table 2.

It can be seen from Table ₂ that the larger the k value is, the larger the value _of X ₁ and X ₂ is, and the larger the value of r ₁ and r ₂ is. _1. The larger the r ₂ , the more favorable it is because the radians of r ₁ and r ₂ need to be specially ground with a grinding wheel, so that the roughness of the radian part will be very low after grinding, and the values of X ₁ and X ₂ will increase. However, when the k value is too large and exceeds 0.7, the remaining length of the straight section will be too short, resulting in the original roughness can only be maintained at a lower percentage of the original step width, which reduces the friction force on the surface of the strip furnace roll. Easy to stray. The smaller the value of k, the smaller the values of X ₁ and X ₂ and the smaller the values of r ₁ and r ₂ , the smaller the influence on the roughness of the roll surface will be, but the radian part r is too small, resulting in a boss mark. Therefore, the value range of the coefficient k is preferably limited to 0.05-0.07.

From the above, it can be seen that the continuous annealing furnace roll of the present invention overcomes the defects in the prior art by optimizing the structure of the double taper. To prevent the problems of buckling and deviation, on the other hand, by optimizing the taper of the furnace roll boss, the problem of lateral scratches or indentation scratches caused by the furnace rolls in the prior art to the strip steel is solved. The use of the continuous annealing furnace roll of the present invention can greatly improve the production efficiency of the strip steel and the quality of the obtained strip steel products.

It should be noted that the prior art part in the protection scope of the present invention is not limited to the examples given in this application document, and all prior art that does not contradict the solution of the present invention, including but not limited to the prior art Patent documents, prior publications, prior publications, etc., can all be included in the protection scope of the present invention.

In addition, the combination of the technical features in this case is not limited to the combination described in the claims of this case or the combination described in the specific embodiments, and all the technical features described in this case can be freely combined or combined in any way, unless conflict with each other.

It should also be noted that the above-listed embodiments are only specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and the similar changes or deformations made subsequently can be directly derived from the contents disclosed in the present invention or can be easily thought of by those skilled in the art, and all belong to the protection scope of the present invention. .

Claims (8)

1. A continuous annealing furnace roll, characterized in that it is set as a double-tapered roll, and the double-tapered roll comprises: a straight section located in the middle, a a first taper segment, and a second taper segment disposed next to each first taper segment, wherein the taper of the second taper segment is different from that of the first taper segment; wherein there is a first transition circle between the straight segment and the first taper segment an arc, with a second transition arc between the first taper segment and the second taper segment; The radius r ₁ of the first transition arc and the radius r ₂ of the second transition arc are respectively obtained based on the following models: r ₁ =2×X ₁ /θ ₁ r ₂ =2×X ₂ /(θ ₁ −θ ₂ ) X ₁ =X ₂ =k×D ₀ Wherein, D ₀ is the diameter of the straight section, k is a coefficient; θ ₁ and θ ₂ are the taper angle of the first taper section and the taper angle of the second taper section, respectively, and the value of the coefficient k is 0.05-0.07. 2 . The continuous annealing furnace roll according to claim 1 , wherein the length in the axial direction is 2000-2300 mm. 3 . 3 . The continuous annealing furnace roll according to claim 1 , wherein the diameter of the straight section is 800-1000 mm. 4 . 4. The continuous annealing furnace roll according to any one of claims 1 to 3, wherein the total crown of the continuous annealing furnace roll is set as C, and the total crown C is obtained based on the following model : C=K ₀ ·(Tr－Ts)×D ₀ /2+C ₀ Wherein, K ₀ is the thermal expansion coefficient of the furnace roll, D ₀ is the diameter of the straight section, Tr is the furnace roll temperature, Ts is the strip temperature, and C ₀ is the reference crown. 5 . The continuous annealing furnace roll according to claim 4 , wherein the value of the reference crown C ₀ ranges from 0.1 to 1.5. 6 . 6. The continuous annealing furnace roll according to claim 4, wherein the total crown C is the sum of the crown C1 of the first tapered section and the crown C2 of the second tapered section, wherein C1/ C2=1.2～1.5. 7 . The continuous annealing furnace roll according to claim 4 , wherein the furnace roll temperature Tr has a value range of 920° C. to 950° C., and/or the strip temperature Ts has a value range of 780° C. to 880° C. 8 . °C. 8 . The continuous annealing furnace roll according to claim 4 , wherein the thermal expansion coefficient ranges from 15×10 ⁻⁶ to 30×10 ⁻⁶ , and the dimension is 1/°C. 9 .

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