JPS63144810A - Method for grinding roll online - Google Patents

Abstract

PURPOSE:To prevent an abnormal step difference causing on a rolled stock by commencing a grinding from the respective right and left max. wear step differences and those outside parts among the roll wear step difference located at the position where the succeeding rolled stock passes. CONSTITUTION:After rolling a rolled stock, the plate pass width 3 of the succeeding rolled stock is recognized, the max. wear step difference 2b within the plate pass width 3 of the succeeding rolled stock is judged and the width at the inner side of the max. wear step difference is taken as a nongrinding width 9. The outside (grinding part 16) of the nongrinding width is ground so that the wear step difference thereof may be eliminated as far as possible until the succeeding rolled stock is passed. The a max. wear step difference 2b is thus reduced up to 2c by grinding at the rolling time of succeeding rolled stock and a normal profile 4 in the width direction is efficiently obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an online roll grinding method for continuous rolling of steel strips, etc.

[Conventional technology]

The 6a-ru is used for rolling, and a portion corresponding to its width is worn out each time the rolled material is passed through. Therefore, when a plurality of rolled materials with different widths are passed through, the roll surface has a symmetrical af
A wear step of 1 is formed.

When a rolled material having a width wider than the width of the wear step is passed, an abnormal step occurs in the width direction profile of the rolled material, so in order to prevent this abnormal step, grinding is performed to reduce the step on the roll surface. The abnormal step in the width direction profile is
As shown in the figure. In Fig. 5, l is the roll wear profile, 2 is the roll wear level difference, 2b is the maximum wear level difference, 3 is the rolling material being passed through, 4 is the width direction profile of the rolled material, and 5 is the abnormal level difference in the rolled material. .

For such a roll wear level difference 2, when grinding is carried out by pressing a whetstone against a rolling roll 1 For example, the roll body length of the whetstone to make equipment easier to understand 1000 When grinding is carried out at a constant rate during roll machining, the amount of grinding is the same throughout the length of the roll body (depth), and the level difference in roll wear does not become small. An example using one grindstone is shown in Fig. 6. When the grinding wheel 7 is pressed against the rotating roll R having the roll wear profile 1 by a device (not shown) and sent in the direction of arrow 8 by a feeding device (not shown), the grinding t-6 is constant during the long erosion of the roll body. Therefore, the roll level difference 2a after grinding does not become smaller than the roll wear level difference 2 by 4.

Therefore, conventionally, as shown in Fig. 7, the worn part of the rolled material due to the passing of the plate is made into a non-grinding width 9 where no grinding is performed, and when the grinding wheel 7 passes there, the pressing of the grinding wheel is stopped, and the parts that are not worn and need grinding are removed. A method of pressing a grindstone only on part 10 to make the roll profile flat (for example, Japanese Patent Application Laid-Open No. 59-1203
Publication No. 07, etc.) were taken. And from now on, the fifth
If there are multiple roll wear steps as shown in the figure, repeat the grinding method shown in Figure 7 and remove the roll body long ends 1 to 1, which are the important parts of the roll to be ground, for example, the shaded area in Figure 8. It is conceivable that parts 11, 12, 13, 14, and 15 are sequentially ground. The same applies when a plurality of grindstones are provided between the lengths of the wheels.

[Problem that the invention seeks to solve]

In some cases, grinding is possible to completely eliminate roll wear steps caused by roll wear each time the rolled material is passed through.

For cases where only rolled materials of the same width are rolled.

It is sufficient to grind as shown in Fig. 7 with the non-grinding width = the retrograde width of the immediately preceding material, but in actual rolling, not only rolled materials with the same width, but also roll wear speed may exceed the grinding speed. Sometimes it goes around. In this case, as rolling progresses, grinding cannot be completed in time, and roll wear steps remain on the roll surface. At this time, if the grinding is performed in the order shown in FIG. 8 from the long end of the roll body 1kl11, which is the part of the roll that requires grinding, a problem will occur. ψ1 is, as shown in Figure 9, compared to the roll wear profile 1 before grinding, when grinding is started from the long end of the roll body, which reduces the roll wear step, only the grinding part 16 is ground before the next material is rolled. Suppose that is possible. In this case, if the trailing plate width 3 of the next material is narrow enough to come inside the grinding part 16, the carving of the maximum wear step 2b will create a width direction profile 4 that surrounds the abnormal step 5, which is inconvenient.

As mentioned above, when a rolled material with a wide width is being passed through, and the wear rate exceeds the grinding speed, and roll wear steps remain on the roll surface, the present invention can be used to limit the rolling time until the next material is rolled. It is an object of the present invention to provide an online roll polishing method that does not form an abnormal step in the width direction profile of a subsequently rolled material within a specified time.

[Means for solving problems]

The gist of the present invention is that in online roll grinding, in which grinding is performed by pressing a grindstone against a roll that has a wear step created by rolling, the maximum wear step on each side of the roll wear step that exists at the position where the next rolled material passes. This is an online roll grinding method characterized by starting grinding from their outer parts.

[For production]

In general, the adverse effect of the roll wear level difference on the profile in the width direction of the threaded material appears as the larger the individual roll wear level difference within one strip area, the larger the abnormal level difference in the threaded material. Therefore, even if the roll wear amount is the same.

If the individual size of the roll wear step is large, the abnormal step will have an adverse effect on the width direction profile.

If the individual sizes are small, there will be almost no abnormal steps in the threaded material, and it will be the same as if the entire crown of the threaded material had become larger. The former is shown in FIG. 5, and the latter is shown in FIG. In such a case, in the former case, the maximum wear level difference 2b is large as shown in FIG.
remains, but in the latter Fig. 1θ, each roll wear stage M
2 is not large, so there is almost no abnormal level difference in profile 4 in the width direction of the rolled material, and it does not pose a problem.The roll curve becomes a concave curve approximately as shown by curve 6a due to roll wear, so it appears as if the entire crown of the rolled material However, this problem can be avoided by controlling the crown of the rolled material using conventional crown control techniques such as a work roll bending device or a roll crossing device (not shown).

In general, the method of grinding is carried out sequentially starting from the part where the roll remains largely worn (both ends of the roll body length), and grinding is not completed in time, causing the main problem. There was a problem in that the next rolling material was blanked even though the maximum wear level difference that caused this remained.

Therefore, in the present invention, by starting grinding from the problematic maximum wear step, even if the wear rate is higher than the grinding speed, the maximum wear step is reduced by the time the next rolled material is passed. Maintain a roll profile as shown in Figure 1O.

This makes it possible to avoid abnormal steps from occurring in the rolled material.

A specific implementation method will be explained with reference to FIGS. 1 and 2. In Figure 1, 1a is the roll profile after grinding, 2C
indicates a wear level difference in which the maximum wear level difference 2b is reduced by grinding, and in the flow chart (Fig. 2), I to D indicate each process. The grinding method is as follows.

First, after rolling the rolled material (process worker), it is recognized that the body rolled material is being passed through 3 (process B). Then, the maximum wear step 2b within the strip width 3 of the primary rolled material is determined (Step 0).

The inner width of the crotch wear step part is set as the non-grinding width 9, and the wear step is minimized by the time the next rolled material is passed through the outside of the non-grinding width 81J (see Fig. ) (Step D).

It should be noted that the next rolling material is in a dairy product during passing, and can be obtained by passing it to the needle side during rolling. In addition, in the ninth step of determining the maximum wear step 2b within the strip width 3 of the primary rolled material, the roll wear profile 1 is obtained as follows, and from the wear profile, the roll body length of the approximately symmetrical roll wear step is determined. Maximum wear step 2b is the largest wear step on the left and right that exists at the position where the primary rolled material passes, with the same position and size.
It is determined that The roll wear profile l is determined by measuring the roll wear profile directly using an online roll profile meter, and by predicting the roll wear profile. The former is possible by installing online roll profile meter equipment,
The latter is based on the estimation of the amount of roll wear δ using equation (1), and predicts that roll wear will progress by the amount of time the rolled material passes, and if the wear of the rolled material from the start of roll use is calculated, the roll Prediction of wear profile 1 becomes possible.

δ: Amount of wear a=t<K-L-p)・(1) K: o-le m class coefficient: 4 length of rolling P: rolling load In this way, the maximum wear level difference is 2b at the time of next rolling and pounding.
is reduced to 2c by grinding, and a normal width direction profile 4 can be efficiently obtained.

〔Example〕

In this example, an online roll grinding section [with a grinding method] was installed for pressing the grindstone, and then in a hot finishing rolling mill (not shown), the product thickness of the rolled material was the same (2 m), and the middle wide material (width 1280 mm) was installed. ), medium-width material (width 1000), and narrow-width material (width 800) were passed alternately, and the results are shown in Figures 3 and 14, where Figure 3 is the same as Figure 2. FIG. 4 shows a comparative example in which grinding was carried out sequentially from both ends of the roll body length using the conventional technique (FIGS. 7 and 8).

In Figures 3 and 4, 3a is threading the wide material, 3b
18 is the roll profile of the used curve, and roll wear profile 1 became as shown in the figure due to rolling of medium width and narrow width materials. The grinding portion 16 is ground using an on-ji 1 roll grinding device to obtain a roll profile la after grinding. A step 2a is transferred to the width direction profile 4 of the wide material rolled by this roll, and an abnormal step 5 occurs in the comparative example (FIG. 4). In addition, Figures 3 and 4 show the finishing rolling mill (
11-6) from stand No. 4.

The roll profiles of the other stands were almost similar.

As can be seen from FIGS. 3 and 4, in the embodiment of the present invention (FIG. 3), before rolling the wide material, In order to reduce the created wear level difference, grinding was started from the level difference part and both outside sides thereof, so the maximum wear level difference 2b was eliminated and the width direction profile 4 of the wide material was normal, but it was not possible with the conventional grinding method. In the case of 19 pieces (Fig. 4), the fcM wear step has almost disappeared, but the roll step in the width of the wide material remains, and the wide material is made of wide material and medium width material. An abnormal level difference 5 has occurred in the width direction profile 4 of .

As described above, it can be seen that by efficiently grinding according to the present invention when rolled materials having different widths are passed alternately, it is possible to avoid different layer steps in the profile in the width direction of the rolled material.

〔Effect of the invention〕

According to the online one-roll grinding method of the present invention, even if a plurality of abrasion steps occur on the roll surface in delayed compression grinding such as Tei et al., the difference is due to the plurality of abrasion steps! ! 4 This has the effect of preventing the formation of a regular stepped crown in one area.

[Brief explanation of the drawing]

FIG. 1 shows a cross section of the upper half of the worn roll for the purpose of explaining the roll grinding method of the present invention, and also shows a cross section of the profile of a rolled material that has been ground according to the present invention. Fig. 2 is a flowchart for explaining the steps of the roll grinding method of the present invention, Fig. 3 is a sectional view for explaining the profile of a worn roll and rolled material according to an embodiment of the present invention, and Fig. 4 is a comparative example. A sectional view for explaining. FIG. 5 is a cross-sectional view for explaining roll wear caused by pressure grinding and the product plate profile. Figure 6 is a cross-sectional view to explain the grinding state after grinding the entire surface of the worn roll while keeping the force constant when pressing the grindstone. Figures 7 and 8 illustrate the conventional roll grinding method. Cross-sectional view for. FIG. 9 is a side view for explaining the roll profile and the grinding plate profile when roll grinding is performed by the conventional method. FIG. 10 is a sectional view for explaining the grinding method of the present invention in comparison with FIG. 9. 1... Roll wear profile, la... Roll profile after grinding, 2... Roll wear step, 2a...
・Roll step after grinding, 2b...Maximum wear step, 3.
...During sheet threading, 4...Width profile, 5...Abnormal step. 6...Grinding t, 6a...Curve, 7...Whetstone, 9
... Non-grinding width, 10... Grinding required part, 16... Grinding part, 18... Roll profile before use. Agent Masu Masaaki Akizawa Mitsunobu 1 person 71'1 figure piece 2 figure 71'5 figure 71'6 figure piece 7 figure

Claims (1)

[Claims] (1) In online roll grinding, in which grinding is performed by pressing a grindstone against a roll that has a wear step created by rolling, the maximum wear step portions on the left and right sides of the roll wear steps that exist at the position where the next rolled material passes, and the outer side thereof An online roll grinding method characterized by starting grinding from the part.