JPS60231560A - Shearing method of billet containing unsolidified part - Google Patents

Abstract

PURPOSE:To increase cutting capacity for a billet by forming the cutting edge shape of upper and lower indenting tools constituted of parted shearing tools and complementing tools into a specific are shape and subjecting the billet to indenting to a specific ratio then shearing the ingot by shearing tools. CONSTITUTION:The half-split shearing tools and half-split complementing tools which are bisected are joined to constitute respectively the upper and lower indenting tools. The cutting edge shape of these upper and lower indenting tools is made into the arc shape of which the radius at the top end thereof is about >=40% of the thickness of the billet. The billet is indented down to 20% of the thickness by using said tools, then the remaining wall thickness is sheared by the upper and lower half-split shearing tools. High press is thus executed with the same press capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention #'i relates to a method for in-line dividing continuous casting H in which the inner core surrounded by a solidified shell is unsolidified in a continuous casting line, particularly a method of dividing by indentation shearing.

Regarding the #JJ cutting method of continuous cast pieces in a continuous casting line, conventional gas cutting methods and simple shearing methods using a press device are generally used. However, the gas cutting method is
Since the time required for 7Jllr is long and the cutting loss is large, #-i cannot be said to be a preferable cutting method from the viewpoint of energy saving and yield improvement. On the other hand, even with the simple shear force method using a press, the required shear load is large in the case of large cross-section slabs and bloom materials, so it is necessary to upgrade the press equipment.

In the cutting process of continuous casting H, the indentation shearing force method is known in which indentation is first performed and the narrowed portion is sheared (for example, see Japanese Patent Application Laid-Open No. 105858/1983).

The indentation shear force method reduces the burden on shear press equipment compared to the simple shear method, but requires press equipment with a large force for indentation processing. JP-A-1 does not teach anything about the relationship between the press equipment for indentation and the press equipment for shearing, or the relationship between the two during the transition from indentation to shearing.

Regarding this point, the present applicant's Japanese Patent Application No. 75621/1983 proposes a method for in-line indentation processing in a continuous casting line.
Subsequent shearing without interruption and with the same press setup
The present invention discloses a technology that enables indentation to be carried out in the early half of the stroke and in the latter half of the shearing stroke during one stroke using the IPT1i. The split tools act as an integrated pushing tool, and in the subsequent shearing process, only the upper and lower half-split shearing tools work as a pair as a shearing tool, and this configuration makes it possible to link both processes. However, regarding tools that are shared, the shape of the tool that is suitable for indentation, the shape of the tool that is suitable for shearing, and the amount +1: Can you adjust or compromise?
What is the relationship between fIA and the required pressing force l, how should it be adjusted, and what is the relationship between the shape of the indentation tool, deformation of the indentation process, and the closure and sealing of the unsolidified part of the chain. Various interrelated issues, such as whether the

The present invention has been made to solve these problems, and basically involves in-line (cutting) continuous cast slabs including unsolidified parts in a continuous casting line. Rice #l in molten steel state by indentation process
i! Completion of crimping of the if part and subsequent shearing, as well as performing indentation and subsequent shearing within a range where the indentation load during indentation does not exceed the shearing load during subsequent shearing. Do it like this. The method of the present invention that concretely realizes Jin's basic solution idea is as follows:
For the purpose of cutting WT of unsolidified continuous slabs on a continuous casting line, a half-splitting shearing tool and a half-splitting complementary tool are combined to cut the continuous slab into pieces with a cutting edge shape that has a radius at the tip. The indentation process is performed to approximately 20% of the plate thickness using an arc-shaped tool that is approximately 4096 mm or more of the plate thickness, and then the shearing process is performed using an upper and lower half shearing tool.
-Characteristics.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings and specific examples to clarify its characteristics.

It is not obvious whether the conventional indentation shearing force method can reduce the required pressing force l compared to the case of simple shearing.

The required press force 1 for indentation may be even larger than the press force 1 for shearing under one condition. Furthermore, it is not known whether the unsolidified portion of the inner core of a continuous slab can be crimped during the pressing process.

In the method of the present invention, the indentation process is carried out within a range in which the necessary press force required for the indentation process does not exceed the necessary press force 1t required for shearing lFT under the corresponding conditions - the indentation amount. Therefore, throughout the entire process of indentation shearing, the required pressing force 1 does not exceed that of simple shearing. At the same time, in the present invention, the continuous slab including the unsolidified part is indented within the above range to complete the closed crimping of the unsolidified part, so as to prevent the unsolidified molten steel from flowing out during subsequent shearing. Make it. As a result of satisfying both conditions, it is not necessary to use large-capacity press equipment, and the equipment layout can be simplified by making it possible to share one press equipment for indentation and shearing. This makes it possible to realize continuous indentation processing and judgment, and to improve the rolling yield due to the quality of the cut. Furthermore, by making vJ#r of the slab including the unsolidified portion possible, high temperature Pft can be carried out to make the pressure in the post-process advantageous and energy saving can be promoted.

In order to reproduce the present invention, hot work steel was actually used as a WIc material, and indentation and shearing were performed using tools with various cutting edge shapes, and the required press load and indentation amount for each were actually measured. The first
As shown in Figure 1), the cross-sectional dimensions are height 38mm and width 5mm.
5mm, with a cavity 5mm high and 25mm wide in the center, made of material 545 with an unsolidified rate of 5/68 = 13.15%.
By indentation using 1000'C hot steel!'!
2! The closed state of the sinus was actually measured. Figure 1 (0) shows the cross-sectional shape of the arc-shaped tool used in the present invention. The following table shows the results of the above confirmation test.

The symbols in the table above are as follows.

2W: -(W) of flat tool R: Tip radius of arcuate tool CM) 2θ: Loss angle of V-shaped tool 8: Indentation 11 (4) H: Continuous slab sample height ff) B: Continuous slab Sample width (4) kO: Average deformation resistance (kgf/d) PF: Maximum load during indentation (kgf) P8: Maximum load during shearing (k
gf) Figure 2 summarizes the results of the verification test, and shows the relationship between indentation 1 on the horizontal axis and load per cross-sectional area of the sample on the vertical axis, and the relationship between indentation and shearing. It is. In Fig. 2, the boundary line (C) between closed and unclosed cavities of the sample for reproduction of the continuous cast piece containing unsolidified 81I is also drawn, and the unclosed fR region is・Nching is applied to make it distinguishable. 2i2 Difference between unclosed and closed sinuses t'i'! It can be easily determined whether the light direction passes in the sinus direction or not. The photograph in Fig. 6 0) is of the invention range H, the tip radius R15tm, R/HO, 39
The cross section shows the deformation state of the Flc material when it is rolled down by 11.7 tons using an arcuate tool with a load of 19.7 tons. The degree of closure was sufficient. On the other hand, the photograph in Figure 6 (b) shows the deformed state of the sample in cross section when it was rolled down by 14.9 mm with a load of 12.15 tons using a V-shaped tool with a loss angle of 90° and a width of 4Q mm. . Despite the large number of manuscripts, the closure was insufficient.

The following knowledge can be obtained by combining the results of the above demonstration tests.

a) For flat tools and arcuate tools, if the contact width between the tool and the sample is approximately half the plate thickness, the cavity can be sufficiently crimped by applying an indentation of about 20%.
It can then be sheared. However, with a flat tool, the indentation load increases rapidly relative to the indentation amount, and when the indentation depth exceeds 1096, the indentation load becomes significantly larger than the shearing load, so a reduction in the required pressing force due to indentation shear wT cannot be expected.

b) With an arc-shaped tool, even if the arc radius is 0.69 of the sample wall thickness, the sample cavity can be closed, and the indentation load becomes equal to the shear load.

If the arc radius is made even smaller, the indentation press charge will be reduced, but this will be disadvantageous for closing the cavity M. On the other hand, if an extremely large arc radius is given, the tool will approach the tendency of a flat tool.

c) With a V-shaped tool, the indentation load is less than the shearing load up to about 30% indentation, but the cavity cannot be closed with a single point of indentation and shear cross-over, and this tendency is large if the forfeiture angle is reduced. becomes.

Based on the above knowledge, an arc-shaped tool with a tip radius of approximately 40,515 mm or more of the thickness of the continuous slab was selected as a pushing tool that combines a half-splitting shearing tool and a half-splitting supplementary tool to perform pushing into the plate. Shearing was performed to 20% of the thickness, and then shearing was performed using a half-splitting shearing tool that released the constraint of the cutting complementary tool to 5g.
If casting A and H are cut, the above-mentioned basic idea of the present invention can be realized simultaneously.

According to the present invention having the above configuration and operation, the following effects can be achieved.

a) Maximum Greska l in t7JIFI machining of continuous cast material
can be reduced compared to conventional technology, increasing cutting capacity for existing in-line press equipment,
Furthermore, if BA is applied to a newly installed press machine, a highly economical press machine ii can be realized with the same press capacity.

b) Conventional gas 17IIIJ for large cross-section continuously cast materials
Since the cutting time is shorter than the T-force method, energy savings can be achieved. Moreover, since the continuously cast material can be cut in a high temperature state including the unsolidified portion, energy conservation can be promoted by utilizing the retained heat 1.

C) Compared to the conventional gas cutting method and the simple shear force method using a press device, the yield is improved because the indentation process is performed.

d) Other improvements such as improved productivity and reduced surface defects can be expected.

[Brief explanation of the drawing]

FIG. 1(a) is a perspective view showing the state of the confirmation test of the present invention;
Fig. 1 (b) is a cross-sectional view of the tip shape of the arc-shaped indentation tool used in the present invention, and Fig. 2 is a horizontal indentation [
Figure 6 (U) is a cross-sectional photograph showing the indentation results of a sample for reproduction according to the present invention, and the third factor (B) is a diagram showing the relationship between the load per cross-sectional area on the vertical axis for various tool shapes, and the third factor (B) is V for comparison. It is a cross-sectional photograph showing the result of indentation of a reproduction sample using a shape tool. Patent applicant's representative name Patent attorney Kaku 1) Yoshihiro (A) 3 diagrams (0 small procedure amendment (method) % formula % 1, Indication of case 1982 Patent Application No. 8880
2 No. 2, Title of the invention Method for shearing continuous slabs including unsolidified parts 3, Relationship with the amended case Patent Applicant Representative Fuyuhiko Maki 4 Agent Address 650 Address Chuo-ku, Kobe City Higashimachi 123-1 Trade Building 9
Floor Telephone Kobe (078) 321-8822 Representative Name Patent Attorney (6586) Corner 1) Yoshihiro j-・'l
・' (2) Drawings (Figure 3 (A) (R) - 1 copy of the attached sheet. Rhyme 3 (A)

Claims (1)

[Claims] 2 before the condensation is completed on the continuous casting line! ! Push in the casting H inline! l! For the purpose of cutting J#, the upper and lower pushing tools are combined with a 9-half shearing tool and a halving complementary tool, and the cutting edge shape is such that the radius at the tip is approximately 40% of the thickness of the continuous slab. The above circular arc-shaped tool is used to perform indentation processing up to approximately 20% of the board thickness, and then the upper and lower half shearing tools are used to cut and shear the wall thickness. Cast H shear force method.