JPS61288916A - Cutting method for bar steel billet - Google Patents

Abstract

PURPOSE:To enhance weight accuracy in a bar steel and improve its production yield rate, by weighing the preceding rolled broom while measuring the total length of a billet rolled from said broom and obtaining the unit weight of the preceding rolled bloom. CONSTITUTION:The method measures weight A of a bloom (b), passing through a large cutter 5, by a weighing machine 6. The bloom (b) is rolled into a continuous billet (c) by a cogging mill 7 and a continuous steel piece rolling mill 8. The total length B of the continuous billet (c) is measured by a measuring machine of a measuring roll 9 in an outlet side of the continuous rolling mill 8. Assuming A1, B1 respectively for weight and total length of the first billet, a relation, where A1/B1=C1kg/m, is used for unit weight of the billet when it is actually rolled. Next for the second rolled billet,the method, using the unit weight C1 obtained in the assigned unit weight by a flying shear 10. Hereinafter, the method successively repeats cutting. In this way,a yield rate can be improved by enhancing weight accuracy.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is applied to a t-th branching factory for improving the single-strip yield in a steel bar factory when EE rolling cuts Vilento and rolling it into steel strips. The weight of the specified billet is divided into 9 cutting methods.

(Prior art) Steel ingots, gums, billets, #1 strips (billets for steel bar mills in the middle of a series of copper strip rolling production processes are 1 sized, 1 layer, 1 specified billet T- when required) This is because when the product length is specified at the time of ordering the bar #I etc., the unit weight of the resulting billet must also be determined in order to improve the yield of the steel bar factory. This is because it is specified.

In this case, the sizing billet O weight IIM degree will have a ripple effect and increase or decrease the yield of one factory. Calculated by billet Jlitid.

Billet unit weight (kg/billet); [acceptance]: Length - x sampling book & (billet/billet) x note dimension unit type 1 (
#/m) f-Kronpros-+Sample Loss-)+(1
- Scale loss) Conventionally, when heavy 1 designated vilent is required, standard unit type 1 (ky
/ m) to billet) l length - f: Calculate, l/7
It is cut off. An example of calculating the unit weight and cutting purity is shown below.

155-square billet, 2200#, fixed size case.

Hot [4 pieces 1tl -1m X O, 155m X
O, 155m x 7850# / j + 1.015
(Shrinking allowance from '?00''C) xO, 5% (shape factor) Heat 185.5#/m Cutting length -2200# +IB5.54 rin 119898M
(Problems to be Solved by the Invention) The first mfi (#/m) used in the prior art is a representative value, and the actual unit weight varies slightly depending on the rolling process. In the case of the image side, the unit type l is not constant at 185.51 Vm, but varies in a range of about 182 to 185 Vm/m in actual rolling.

As a result, the billet weight will not be the specified 2200 kg, but will vary between 2182 and 2218 kg, resulting in poor weight accuracy.

When this billet is rolled into steel strips at a steel bar mill, the desired rolling length is not achieved and the desired product cannot be obtained. 'l, extra length will occur, resulting in a decrease in yield at the steel bar factory.

One solution to obtain billets with a predetermined amount of It is to set the unit Itill to a constant value, in the previous example 18i 5#/m K
: There is a way to get closer and stabilize it. However, there are many factors that affect the unit weight, such as the steel type of the rolled material, the thickness of the rolled material, the width expansion and retention of the mold 1, the roll diameter, the low/l' wear condition, and the low IA/rotation failure, and by adjusting these conditions, 41 It is very difficult to bring the weight 1 close to a constant value.

The present invention deals with the above-mentioned problems of the prior art 1 designation 11
! The purpose is to make it possible to obtain 1 billet 1# times. .

(Problem 1-#Ninth means to decide 1 Effect, Example) Unexploded f14 is a unit weight (hyrn) that vibrates every time it is rolled.
Calculate the billet cross-sectional length t- from the obtained unit m and calculate vJwr.

The basic idea is to obtain the unit type 1 in the preceding 8E rolling between the preceding and vk rolling and apply it to the cutting in the subsequent rolling.

Based on this, the new method of the present invention for dual use of vilent is composed of groom and vilent.

In the middle of the continuous rolling process of the steel strip and subsequent steel strip, the bloom rolled in the preceding rolling is weighed using a weight IAt'' weighing machine, and the total length B of the rolled billet is measured from this bloom using a length measuring machine. The unit type 10t of the preceding rolling is determined by A/Tsukudani, and the cutting length is determined using the unit type 1 for the billet cutting of the next 6tR rolling, and the cutting length is determined for each subsequent rolling. The procedure is characterized by continuous repetition.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below with reference to the accompanying drawings. The figure is a step-by-step overview of the continuous process of blooming.

(1) Soaking furnace (tt) X or heating furnace (2), l
l! ! The rolled steel ingot (at is rolled in the first blooming mill (3), treated with a surface solvent in (4), and then topped with a large shearing machine (5).

The unattached part of the bottom was cut off.

(1) In the present invention, this disconnected nine plumes (b)
t” Weigh the heavy Bh using the weighing machine (6). After this, the bloom is applied to the second blooming press [machine (7), continuous billet rolling machine (
8) and then rolled into a continuous billet (CL).During this process, there is almost no reward for the amount of gum loaded.

Strictly speaking, the rolling scale is separated by @, but it is small in terms of 1ML and can be ignored here. Measure the total length Et-#F of the illegal billet (c) using a length measuring machine consisting of 9).

The steps of the method of the present invention include weighing 1 with a weighing machine (6).
1L7'l: The weight of the first bloom is set to Al-.

Billet total length le measured on measuring roll (9)
B s- and * A s ” B I= 0+ C
~/m) is calculated, and the unit of billet in actual rolling is 11
* Increase Or (kg/m).

(7) For the rolled billet with the second grain to be rolled next, calculate 7 using the first grain. , unit m theory Or (kg/m
) to calculate the cutting length and cut the continuous billet into the specified unit weight billet. For the rolling of the second wood, in the same way as the first wood, measure the bloom weight A warehouse, billet total length Bst - % A word + B weight - 〇 wing unit type 11 (#/m) and use it for continuous billet cutting of the third wood. Do it like this.

(Vl) After the 5th grain (D) The v'J cut of the unilateral vilent shall be obtained by rolling in the prior application as described above and performed by applying t unit lid.

(Vl For about 8 to 10 slabs or about 11 ingots produced from one charge of molten steel, M building #'i
Since the rolling conditions are similar between the preceding bloom rolling and the subsequent rolling, the unit type IO change is small. Therefore, by using the above method, the unambiguous MtmN1 degree is much p compared to the case using the conventional technology.
Improve to i.

- If this method is used, if there is a change in rolls, steel type, or charge, there will be no unit m1io that can be applied to determine the cutting point of a continuous billet with the first grain. The t-value obtained from past results is used for this.

■ In addition, if the M degree of this unit Mil# is made the same as above,
All you have to do is perform learning calculations using OPU K, and even if the steel type changes, the unit type 'ki can be estimated at a fairly good level.

(Example 5IJ result) The method of the present invention is applicable because the IJJJ length of bloom rts scale l and rolled nine consecutive vilents is comparable.

It is possible to carry out the process without difficulty and to send a new billet of 1 weight S& to a steel bar mill.

As an example, the following table shows the results of cutting accuracy for a constant weight billet designated as 2000# in comparison with the conventional method.

[Brief explanation of drawings]

The attached drawings are diagrams illustrating, in order of process, the continuous process of rolling and cutting next month's billets in a blooming plant, which is applied to *m of the method of the present invention. (1) Soaking furnace, (2) Heating furnace, (3) First
Blooming mill, (4) φ real scarf, +5>... large shearing machine, (6)... weighing machine, (7) @ φ second blooming mill. (8) 11・Slow ajllPtJEAmb (9) $
+1 i Sha! J n y low step, α0・e flying Vya% (a) @・steel ingot, (blφ・bloom, (C)
・One continuous billet, (Yu...Unit billet◎

Claims (1)

[Claims] During the continuous rolling process of bloom, billet, and steel strip, the weight A of the bloom rolled in the preceding rolling is measured using a weighing machine, and the total length B of the billet rolled from this bloom is measured using a measuring machine. Measure the billet length, calculate the unit weight C of the preceding rolling using A/B, and use the unit weight C to determine the cutting length for cutting the billet in the subsequent rolling. A method for cutting a dual-purpose billet, characterized by continuously repeating this procedure for each rolling.