JPH01210101A - Method for stepless continuous rolling of steel bar stock - Google Patents

Abstract

PURPOSE:To perform finish rolling over an optional length of a stock without gaps by properly supplying steel bar stocks to 2-4 shaping mill groups of specific formation. CONSTITUTION:The total three shaping mill groups 21, 22, 23 are installed for one rough rolling or intermediate rolling mill line 11 obtaining a steel bar stock. The mill group 21 consists of three passes rolling mills 31, 32, 33 provided with a draft adjusting mechanism and the groups 22, 23 also have the same formation. The mill group 21 is constructed to have a percentage reduction of <=15% in the total three passes by use of the draft adjusting mechanism and the rotating axial directions of respective rolling rolls in respective passes are deviated by 90 deg. from each other alternately and a grooved die of rolling rolls is selected from among opening angles of 90-140 deg.. Thus, a steel bar stock delivered from an rough or intermediate rolling line is properly supplied to 2-4 shaping rolling mill groups to perform finish rolling over an optional length of the stock without gaps.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for stepless continuous rolling of long steel (bar steel or wire temperature).

Generally, the hot rolled steel bar material is further processed into final products that are used for various purposes. At this stage of processing, it is desirable that the raw material for processing is finish rolling (tight rolling) in advance to the dimensions of the final product in order to make the processing process easier. Not even.

Therefore, in the rolling stage of long steel, the rough-rolled to intermediate-rolled long steel material is further subjected to a series of finishing rolling, and at this time, the dimensions of the hk finished products used for each of the seven types of applications are adjusted. For this reason, it is required to carry out stepless finish rolling of long steel material over a wide range of dimensions, and it is also required to carry out this process efficiently.

The present invention relates to a stepless continuous rolling method for long steel that meets such demands.

<Conventional technology, its problems> Conventionally, as a method for finish rolling a long steel material, three or four rolling mills (kLa) are arranged vertically and horizontally in an intersecting manner, and each rolling mill on the upstream side A method of adjusting the rolling reduction to regulate the area reduction rate has been proposed (Japanese Patent Application Laid-Open No. 165101/1983).
No. 59-229204), and at least 3
The rolling mills are arranged so that the rotating axes of the rolling rolls are alternately offset by 90 degrees, and the total area reduction rate in each rolling mill is 15% or less, and the area reduction rate in the final two rolling mills is A method of regulating each to 3% or less has been proposed (Japanese Unexamined Patent Publication No. 152302/1983).

However, in these conventional methods, due to their structure, especially the structure in which the rough rolling to intermediate rolling series and the finishing rolling series are fixedly arranged in a 1:1 correspondence, there is a wide range of stepless steps. It is difficult to comply with requests to change finish rolling dimensions,
Another problem is that it is difficult to avoid the occurrence of cuts during the finish rolling operation.

<Problems to be Solved by the Invention and Means for Solving the Problems> The present invention solves the conventional problems as described above and provides an improved stepless continuous rolling method for long steel that meets the above-mentioned demands. It is something.

Therefore, in the present invention, when finish rolling a hot-rolled long steel material, the long steel material is appropriately supplied to forming rolling mill groups 2 to 4 formed by the following 1) and 2), and The present invention relates to a stepless continuous rolling method for long steel, which is characterized by finishing a long steel material to any size without any cuts.

l) Consisting of 2 or 3 passes of rolling mills each equipped with a rolling reduction adjustment mechanism, and each pass totaling 15% (each forming mill group)
A shaping rolling mill group having the following area reduction ratio, 2) The rotation axes of the rolling rolls in each pass are alternately deviated by 90 degrees, and the hole shape of the rolling rolls is 90° to 90°.
Forming rolling mill groups selected from an opening angle of 140 degrees The important point in the present invention is that 2 to 4 predetermined finishing rolling mill groups are selected for the rough rolling to intermediate rolling series for obtaining one long steel material.
According to the finished dimensions required for the bar material,
The bar material is appropriately supplied to the finish rolling train and finish rolled to any size without any gaps.

Hereinafter, the configuration of the present invention will be explained in more detail based on the drawings.

<Embodiments and their effects> FIG. 1 is a system diagram showing one implementation procedure of the present invention. A total of three shaping rolling mill groups (finishing rolling series) 21 for one rough rolling to intermediate rolling series 11 for obtaining long steel material.
, 22.23 are arranged. The long steel material obtained from the rough rolling to intermediate rolling series 11 is appropriately supplied to the shaping rolling mill groups 21, 22, and 23 according to the finished dimensions required for the long steel material, and finish rolled to any desired size without any breaks. It is.

The other shaping rolling mill groups 22 and 23 have similar configurations, but the shaping rolling mill group 21 consists of three passes of rolling 4131 and 32, 33 each equipped with a rolling reduction adjustment mechanism (not shown). The rolls are formed so as to have a reduction in area of 15% or less in total in each pass, and the rotation axes of the rolls in each pass are alternately offset by 90 degrees, and the rolls have a hole shape of 90 to 140 degrees. If the total area reduction rate of 0, which is formed so as to be selected from the opening angle, exceeds 15%, it will be difficult to obtain the specified dimensional accuracy, and if the opening angle of the hole mold is less than 90 degrees, it will be difficult to adjust the hole shape. Although the allowance is large, it causes variations in dimensions, and conversely, if it exceeds 140 degrees, the hole adjustment allowance becomes small, which limits the dimensions that can be rolled with the same hole.

FIG. 2 is an enlarged perspective view showing the arrangement of rolling rolls in each pass in the shaping rolling mill group of FIG. 1. FIG.

The rolling roll 41 of the first rolling mill 31 in the shaping rolling mill group 21 in FIG. 1 is a vertical roll, and the rolling roll 4'
Roll roll 42 of the next rolling mill 32 adjacent to ll[31
are horizontal rolls, and the rolling rolls 43 of the last rolling mill 33 adjacent to the rolling mill 32 are again vertical rolls. Rolls 41, 42, 43 in each pass
The rotating axes of the rolling rolls 41, 42, and 43 are alternately shifted by 90 degrees, and the groove shapes of the rolling rolls 41, 42, and 43 are set to 90 to 140 degrees.
The rolling roll 4 is selected from a relatively narrow opening angle of
1.42.43. Allow some margin for adjustment width of the roll gap,
By appropriately adjusting the roll gap with the rolling down adjustment mechanism, the area reduction ratio of 15% or less in the total of the three passes, preferably as an additional condition to obtain better dimensional accuracy, is
Each pass is formed to have an area reduction rate of 3% or less.

In the present invention, two to four shaping rolling mill groups, which are finish rolling series of long steel materials, are arranged, and each shaping rolling mill group has two
Alternatively, the rolling mill is formed in three passes, and the rotation axes of the rolls in each pass are alternately shifted by 90 degrees, and the hole shape of the rolls is selected from an opening angle of 90 to 140 degrees. The area reduction rate in the group is regulated to 15% or less based on practical viewpoints and test results, and within this regulation range, it is practically reasonable to reduce the rolling dimension of the long steel material to, for example, 50φ±. It is possible to finish up to about 0.15+sm.

In the drawing, three shaping rolling mill groups are arranged for one rough rolling to intermediate rolling series, but in this case, the number of rough rolling to intermediate rolling series may be two, for example. Two to four shaping mill groups are selectively arranged for the rolling to intermediate rolling series, and they are not fixedly arranged in a one-to-one correspondence. The long steel material obtained from the series can be appropriately supplied to 2 to 4 shaping rolling mill groups depending on the finishing dimensions required for the long steel material, and finish rolling can be performed seamlessly to any size. .

<Effects of the Invention> As explained above, one aspect of the present invention is to finish-roll a bar steel material to any size without any gaps.

Therefore, it is possible to efficiently manufacture long steel products with precise dimensions as required.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing one implementation procedure of the present invention, and FIG. 2 is an enlarged perspective view showing the arrangement of rolling rolls in each pass in the shaping rolling mill group of FIG. 1. 11. Rough rolling to intermediate rolling series 21. 22. 23. Shaping rolling mill group 31. 32, 33. Rolling mill 41. 42, 43. φ rolling roll Patent applicant Daido Steel Co., Ltd. Agent Patent attorney Hiroshi Iriyama Figure 1 Figure 2

Claims (1)

[Claims] 1. When finish rolling a hot-rolled long steel material, the long steel material is appropriately supplied to groups 2 to 4 of shaping rolling mills formed by 1) and 2) below. , a stepless continuous rolling method for long steel bars, characterized in that the long steel material is finished to desired dimensions without any cuts. 1) A forming rolling mill group consisting of 2 or 3 passes of rolling mills each equipped with a rolling reduction adjustment mechanism and having a total area reduction of 15% or less for each pass, and 2) The rotation axis of the rolling roll in each pass. are alternately offset by 90 degrees, and the hole shape of the rolling roll is 90 to 90 degrees.
Forming rolling mill group selected from 140 degree opening angle