Metal deforming – By use of roller or roller-like tool-element
Patent
1987-11-13
1989-10-31
Combs, E. Michael
Metal deforming
By use of roller or roller-like tool-element
72234, B21B 108, B21B 122, B21B 2702
Patent
active
048768740
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates to rolling by use of a caliber roll provided in one or a plurality of stands of a continuous hot strip mill and particularly to a rolling method of stably producing a steel strip of deformed section which steel strip varies in thickness in the direction of width.
BACKGROUND ART
Hitherto, regarding a method of providing differences in thickness in the direction of width of a strip, gthere has been known a method of using rolls each provided thereon with a crown or another method of using a roll provided thereon with a groove-like caliber.
The former pertains to an operation of producing usual strips. According to this method, in a case of providing a large difference in thickness, rolls each having a large crown are used in preceding stages of rolling regarding a hot strip mill, and the size of each of the crowns is reduced in accordance with the successive reduction of thickness of a rolled material, thereby forming a crown on the strip without disturbing a contour of the strip. In the case of this method, a widthwise cross-sectional shape of a strip to be formed is limited to a shape of the crown.
In the latter method, a groove is formed in a roll so as to provide a local projection on a strip. For example, this type of method is disclosed in U.S. Pat. No. 3,488,988, Japanese Examined Patent Publication No. 34022/1977, Japanese Unexamined Patent Publication No. 88943/1980 and so forth. Since, in this method, a provision of the thickness difference is effected in a final stand, the shape of a strip will be degraded if a difference in thickness is large between a section defined prior to the rolling which is to be effected at the final stand and another section provided by the rolling in the final stand of the mill, with the result that a defective product will be caused or it will become impossible to effect the rolling at the final stand. Thus, in the method there is a limitation regarding the section which can be imparted to strips. This rolling method is effective when applied to the rolling of a steel strip of deformed section in which a variation in thickness is repeated widthwise with a relatively small pitch. However, in such a case where a pitch "P" showed in FIG. 1 is large and where a thickness of the whole of a steel strip (,i.e., both of a thickness t.sub.1 of a thick portion and another thickness t.sub.2 of a thin portion) is relatively small, that is, in a case where a steel strip of deformed section is of a thin strip shape, a shape of a resultant steel plate has been apt to be degraded with the result that a defective product or defective rolling has been apt to be caused. FIG. 5 illustrates an example of rolling for simultaneously obtaining a pair of deformed section steel strips each similar to that shown in FIG. 1 in which rolling a roll barrel of a rolling mill is effectively utilized to simultaneously provide two sets of deformed section in a steel strip. In the drawing the reference numerals 1 and 3 denote upper and lower working rolls for effecting the rolling to obtain the deformed section steel strip, respectively. Reference numeral 2 denotes a caliber provided on the upper roll 1, and reference numeral 4 denotes a material to be rolled.
The present applicant has already disclosed, in the specification of Japanese Patent Application No. 128880/1984 (Japanese Unexamined Patent Publication No. 9911/1986), a method of rolling by use of roll having caliber so as to produce a good steel strip of a deformed section having a large difference in thickness in the direction of the width thereof, in which method a continuous hot rolling mill having one or a plurality of stands is used. This rolling method of producing a deformed section strip is characterized in that the strip is rolled under the following rolling condition for each stand: defined at the entrance side; h.sub.E is an average thickness (mm) thereof at the entrance side; Ch.sub.D is a thickness difference (mm) of another deformed section defined at the exit side; and h.sub.D is an avera
REFERENCES:
patent: 4672830 (1987-06-01), Tsukamoto et al.
patent: 4703641 (1987-11-01), Yarita et al.
patent: 4730475 (1988-03-01), Ginzburg
Higuchi Norio
Izumihara Yoshikazu
Kakehi Nobuo
Matsumoto Hiromi
Takahashi Yuzuru
Combs E. Michael
Nippon Steel Corporation
LandOfFree
Method of hot rolling steel strip with deformed sections does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of hot rolling steel strip with deformed sections, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of hot rolling steel strip with deformed sections will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-619707