Title of Invention

A CASTING TECHNOLOGY TO A BUILD UP MOLD FOR CONTINUOUS CASTING OF PLATE BILLET

Abstract Disclosed herein is a build-up mold for continuous casting of plate billet, which is consisted of two broad sidewalls and two narrow sidewalls. At both sides of each of the narrow sidewalls, there is respectively provided a row of right triangle like flanges. The bevel of the triangle flange faces inward, one of right angled faces is combined with the inner face of the narrow sidewall, and another right angled face is coplanar with the side face of the narrow sidewall. The bevel of the triangle flange may be planar or a concave cambered surface. The build-up mold according to the invention has advantages of simple construction, reasonable design, by adopting four rows of right triangle flange formed on the two narrow sidewalls, it is possible to change the shape of the corners of the inner chamber of the mold and adopt rounded corner or vertical slope corner instead of right angle, such that the cooling of the molten steel at the corners during solidifying inside the mold to form billet shell is changed to approach one dimensionally cooling from two dimensionally cooling thereby achieving effect of reducing cooling strength at the corners and making the cooling of the billet shell uniform, therefore avoiding the surface defects from occurring due to the non-uniform cooling at the corners of the billet.
Full Text FIELD OF THE INVENTION
The invention relates to a casting technology for metal, especially to a build-up mold for continuous casting of plate billet.
DESCRIPTION OF THE RELATED ART
In current plate billet continuous casting technology, a straight parallel plate mold has an interior chamber defined by two broad sidewalls and two movable narrow sidewalls, and the intersections of the broad sidewalls and the narrow sidewalls, that is, four corner of the interior chamber, have right angled shape. Therefore, as the molten steel at the corners is subjected to two-dimensionally cooling during the process of molten steel solidifying to form billet shell, the solidification speed of the molten steel is so fast that the overall solidification of the casting billet is not uniform and surface defects tend to occur. Meanwhile, as the cooling speed is faster at the corners, the plate billet produced by the right-angled mold is not uniform in surface temperature and tends to produce cracks at the corners. Especially in the production of tube-wire steel (X42, X46, X52, X60, X70 and so on), steel for automobiles and vehicles (A510L, HQ600, SMY490 and so on) and structure steel (Q345A, Q345B and so on), the sheet without subject to skinning treatment always produce edge cracks so as to become a waste product.
SUMMARY OF THE INVENTION
An object of the invention is to provide a build-up mold for continuous casting of plate billet, the interior chamber of which has four corners of rounded angled or vertical-slope angled shape to enhance the quality of the corners.
To achieve the object of the invention, there is provided a build-up mold for continuous casting of plate billet constructed by two broad sidewalls and two narrow sidewalls, wherein at both sides of each of the narrow sidewalls, that is, the inner sides connected with the broad sidewalls, there is respectively provided a row of right triangle like flanges, the bevel of the triangle flange faces inward, one of right angled faces is combined with the inner face of the narrow sidewall, another right angled face is coplanar with the side face of the narrow
sidewall, that is, the another right angled face is the extension of the side face of the narrow
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sidewall. The bevel of the triangle flange is a concave cambered surface, and the radius of the rounded corner of the triangle flange is lmm-15mm. The bevel of the triangle flange is planar, and the length of the vertical-slope edge of the triangle flange is l-15mmxl-15mm.
The narrow sidewall and the triangle flange may be integrally formed, but also may be integrally combined by assembling.
The build-up mold according to the invention has advantages of simple construction, reasonable design, easy to operation and facilitating use. Due to adopting four rows of right triangle flange formed on the two narrow sidewalls so as to change the shape of the corners of the inner chamber of the mold and adopting rounded corner or vertical slope corner instead of prior right angle, the cooling of the molten steel at the corners during solidifying inside the mold to form billet shell is changed to approach one dimensionally cooling from two dimensionally cooling thereby achieving effect of reducing cooling strength at the corners and making the cooling of the billet shell uniform, therefore avoiding the surface defects from occurring due to the non-uniform cooling at the corners of the billet. The production and maintenance of the mold is very simple, the cost of the apparatus is low while reducing the wastage and production cost. Because the corners of the billet is rounded corner or slope angled, the surface temperature thereof is relatively uniform, the difference of temperature between the middle and the edge is reduced, thereby avoiding the problem of cracks because the edge temperature is too low when directly rolling. Adopting the build-up mold according to the invention can enhance the quality of casting billet for tube-wire steel, reduce the defects of cracks formed at edge of the plate, and increase production efficiency.
Brief description of the drawings
Fig.l is a schematic structural diagram of showing a configuration of the narrow sidewall having triangle flanges with the concave cambered surface on the two side edges.
Fig.2 is a schematic structural diagram of showing a configuration of the narrow sidewall having triangle flanges with the planar surface on the two side edges.
Fig.3 is a schematic structural diagram of the build-up mold according the invention.
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Detailed description of the invention
As seen from Fig.3, the build-up mold according the invention is constructed of two broad sidewalls 2 and two narrow sidewalls 1. At both sides of each of the narrow sidewalls, that is, the inner sides connected with the broad sidewalls 2, there is respectively provided a row of right triangle like flanges 3, the bevel of the triangle flange 3 faces inward, one of right angled faces is combined with the inner face of the narrow sidewall 1, another right angled face is coplanar with the side face of the narrow sidewall 1, that is, the another right angled face is the extension of the side face of the narrow sidewall 1 and is connected with the inner face of the broad sidewalls 2 . Preferably, the narrow sidewall 1 and the triangle flange 3 or 4 may be integrally formed, but also may be integrally combined by assembling. By combining the narrow sidewall 1 and the triangle flange 3 or 4 with each other, the corner shape of the interior chamber of the mold may be changed without affecting the adjustment of the width of the mold. The invention can change the corner shape of the interior chamber of the mold by changing the shape of the triangle flange along the bevel. If the triangle flange 3 having a bevel of concave cambered surface is provided (as seen from Figs.l and 3), the interior chamber have rounded corner, and if the triangle flange 4 having a bevel with a planar surface is provided (as seen from Fig.2), the bevel is planar. The size of triangle flange 3 or 4 of the invention may be set according to the demands, with respect to the bevel with a planar surface, the length of the straight bevel edge of the triangle flange 3 is about l-15mmx 1-15mm, and with respect to the bevel with a concave cambered surface, the radius of the rounded corner of the triangle flange 3 is about l-15mm.
Because the mold according to the invention can reduce cooling strength at the corners with respect to tube-wire steel, steel for automobile and vehicle, structural steel and so on, the solidification of the billet shell is relatively uniform, thereby avoiding the surface defects due to the non-uniform solidification and cooling at corners of plate billets. Taking the build-up mold with vertical bevel edge of 5mmx5mm or rounded corner radius of 5mm as a example, a tube-wire steel of X52 with a size of 135mmxl 170mm is subject to pouring test and compared with the conventional right angled mold, the results is listed in table 1. As compared to the conventional right angled mold, it is learned that the build-up mold can substantially reduce the temperature difference between the middle and the edge corners of
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the casting billet, and the occurring chance of cracks at the edge of the casting plate is also substantially reduced.
Table 1 Comparison of pouring test between conventional right angled mold and build-up mold

item right angled mold build-up mold
Normal pouring rate (m/min) 1.8-2.8 1.8-2.8
Depth of whip mark at corner (mm) 0.5-2.5 Temperature difference between corner and middle along broad side of continuous casting billet at out-section (□) 20-40 10-20
Temperature difference between edge and middle along broad side of sheet before finish rolling (□) 15-45 10-30
Rate of edge cracks in rolled metal (%) 4-6 5

WE CLAIM:
1. A build-up mold for continuous casting of plate billet constructed by two broad sidewalls
(2) and two narrow sidewalls (1), wherein at both sides of each of the narrow sidewalls
(1), that is, the inner sides connected with the broad sidewalls (2), there is respectively
provided a row of right triangle like flanges (3 or 4), the bevel of the triangle flange (3 or
4) faces inward, one of right angled faces is combined with the inner face of the narrow
sidewall (1), another right angled face is coplanar with the side face of the narrow
sidewall (1), that is, the another right angled face is the extension of the side face of the
narrow sidewall (1), the bevel of the triangle flange (3) is a concave cambered surface
and the radius of the rounded corner of the triangle flange is lmm-15mm, the bevel of
the triangle flange (4) is planar and the length of the vertical-slope edge of the triangle
flange is 1-15mm x 1-15mm.
2. The build-up mold according to claim 1, wherein the narrow sidewall (1) and the triangle
flange (3 or 4) are integrally formed or integrally combined by assembling.


Dated this 21st day of September 2007

Disclosed herein is a build-up mold for continuous casting of plate billet, which is consisted of two broad sidewalls and two narrow sidewalls. At both sides of each of the narrow sidewalls, there is respectively provided a row of right triangle like flanges. The bevel of the triangle flange faces inward, one of right angled faces is combined with the inner face of the narrow sidewall, and another right angled face is coplanar with the side face of the narrow sidewall. The bevel of the triangle flange may be planar or a concave cambered surface. The build-up mold according to the invention has advantages of simple construction, reasonable design, by adopting four rows of right triangle flange formed on the two narrow sidewalls, it is possible to change the shape of the corners of the inner chamber of the mold and adopt rounded corner or vertical slope corner instead of right angle, such that the cooling of the molten steel at the corners during solidifying inside the mold to form billet shell is changed to approach one dimensionally cooling from two dimensionally cooling thereby achieving effect of reducing cooling strength at the corners and making the cooling of the billet shell uniform, therefore avoiding the surface defects from occurring due to the non-uniform cooling at the corners of the billet.

Documents:

03585-kolnp-2007-abstract.pdf

03585-kolnp-2007-claims.pdf

03585-kolnp-2007-correspondence others 1.1.pdf

03585-kolnp-2007-correspondence others.pdf

03585-kolnp-2007-description complete.pdf

03585-kolnp-2007-drawings.pdf

03585-kolnp-2007-form 1.pdf

03585-kolnp-2007-form 18.pdf

03585-kolnp-2007-form 2.pdf

03585-kolnp-2007-form 3.pdf

03585-kolnp-2007-form 5.pdf

03585-kolnp-2007-international exm report.pdf

03585-kolnp-2007-international publication.pdf

03585-kolnp-2007-international search report.pdf

03585-kolnp-2007-pct priority document notification.pdf

03585-kolnp-2007-priority document.pdf

03585-kolnp-2007-translated copy of priority document.pdf

3585-KOLNP-2007-(10-04-2012)-AMANDED PAGES OF SPECIFICATION.pdf

3585-KOLNP-2007-(10-04-2012)-CLAIMS.pdf

3585-KOLNP-2007-(10-04-2012)-CORRESPONDENCE.pdf

3585-KOLNP-2007-(10-04-2012)-FORM-3.pdf

3585-KOLNP-2007-(10-04-2012)-OTHERS.pdf

3585-KOLNP-2007-(15-03-2012)-CORRESPONDENCE.pdf

3585-KOLNP-2007-(21-03-2012)-CORRESPONDENCE.pdf

3585-KOLNP-2007-(23-05-2012)-CORRESPONDENCE.pdf

3585-KOLNP-2007-(27-07-2012)-PETITION UNDER RULE 137.pdf

3585-KOLNP-2007-(28-11-2011)-CORRESPONDENCE.pdf

3585-KOLNP-2007-ABSTRACT 1.1.pdf

3585-KOLNP-2007-AMANDED CLAIMS.pdf

3585-KOLNP-2007-CORRESPONDENCE 1.1.pdf

3585-KOLNP-2007-CORRESPONDENCE 1.5.pdf

3585-kolnp-2007-CORRESPONDENCE-1.2.pdf

3585-KOLNP-2007-CORRESPONDENCE-1.3.pdf

3585-KOLNP-2007-CORRESPONDENCE-1.4.pdf

3585-KOLNP-2007-DESCRIPTION (COMPLETE) 1.1.pdf

3585-KOLNP-2007-DRAWINGS 1.1.pdf

3585-KOLNP-2007-FORM 1-1.1.pdf

3585-KOLNP-2007-FORM 2-1.1.pdf

3585-KOLNP-2007-FORM 3.pdf

3585-KOLNP-2007-INTERNATIONAL SEARCH REPORT.pdf

3585-KOLNP-2007-OTHERS 1.2.pdf

3585-KOLNP-2007-OTHERS-1.1.pdf

3585-KOLNP-2007-OTHERS.pdf

3585-KOLNP-2007-PA.pdf

3585-KOLNP-2007-REPLY TO EXAMINATION REPORT.pdf

abstract-03585-kolnp-2007.jpg


Patent Number 255408
Indian Patent Application Number 3585/KOLNP/2007
PG Journal Number 08/2013
Publication Date 22-Feb-2013
Grant Date 18-Feb-2013
Date of Filing 21-Sep-2007
Name of Patentee ANGANG STEEL COMPANY LIMITED
Applicant Address TIEXI DISTRICT, ANSHAN CITY, LIAONING PROVINCE
Inventors:
# Inventor's Name Inventor's Address
1 TANG, FUPING NO. 396 SOUTH ZHONGHUA ROAD, ANSHAN, LIAONING PROVINCE 114021
2 MA, YONGGANG NO. 396 SOUTH ZHONGHUA ROAD, ANSHAN, LIAONING PROVINCE 114021
3 HUANG, HAODONG NO. 396 SOUTH ZHONGHUA ROAD, ANSHAN, LIAONING PROVINCE 114021
4 WANG, JUN NO. 396 SOUTH ZHONGHUA ROAD, ANSHAN, LIAONING PROVINCE 114021
PCT International Classification Number B22D 11/041
PCT International Application Number PCT/CN2006/000338
PCT International Filing date 2006-03-07
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 200520089594.4 2005-03-07 China