CN1201885C

CN1201885C - Crytallizer for inner wall of continuous casting coated groove

Info

Publication number: CN1201885C
Application number: CN 02109856
Authority: CN
Inventors: 沈明钢
Original assignee: Anshan University of Science and Technology
Current assignee: Anshan University of Science and Technology
Priority date: 2002-06-18
Filing date: 2002-06-18
Publication date: 2005-05-18
Anticipated expiration: 2022-06-18
Also published as: CN1465456A

Abstract

The present invention discloses a crystallizer with continuous casting plated grooves on the inner wall. The inner wall of a continuous casting crystallizer is marked with longitudinal thin grooves, or longitudinal and transverse thin grooves, each groove is 1 to 100 mu m in width and 1 to 500 mu m in depth, and a wear-resistant layer is plated on the inner wall of the continuous casting crystallizer; the primary blank shell is cooled in the whole area of the crystallizer to shrink in volume so as to deform, and the positions between every two grooves are solidified and cooled to shrink in volume so as to deform. The heat transmission conditions of the primary blank shell are even, and the thickness of the blank shell is even so as to reduce surface cracks of the casting blank. The present invention improves the heat transmission evenness of the primary blank shell; meanwhile, the present invention reduces the ratio of air to gaps between the primary blank shell and the crystallizer, enhances the conductive heat flow between the primary blank shell and the crystallizer, increases the cooling speed, can increase the pulling rate of the casting blank, enhances the productivity of continuous casting equipment and the surface temperature of the casting blank, and is favorable to save energy. The casting blank and the wear-resistant layer form contact friction in the continuous casting process through the wear-resistant layer which is additionally plated; before the wear-resistant layer is worn off, the distribution of the grooves marked on the inner wall of the crystallizer does not change so as to extend the service life of the crystallizer with continuous casting grooves on the inner wall.

Description

Crytallizer for inner wall of continuous casting coated groove

Technical field the present invention relates to the production equipment in the metallurgical industry, a kind of crystallizer that especially uses in the casting process.

The present employed continuous cast mold inwall of background technology is a smooth surface.Owing to produce the phase transformation volume contraction during solidification of molten steel, make between initial solidification shell and crystallizer inwall and produce non-uniform gap, directly contact with crystallizer with initial solidification shell and to compare, air gap obviously increases thermal resistance between base shell and crystallizer, non-uniform gap make between base shell and crystallizer conduct heat inhomogeneous, the formation shell thickness is inhomogeneous, concentrates at base shell thin location generation stress, when stress will crack during greater than base shell intensity.The crackle expansion forms slab surface crack in the cooling procedure of subsequent technique, causes the casting billet surface defective.Molten steel is in the very short a period of time that just contacts with crystallizer, and the initial solidification shell of formation is thin, and base shell temperature high temperature difference is big, therefore base shell intensity is low, is subjected to ferrostatic pressure and the effect of base shell coagulated volume convergent force, and the shell thickness degree of irregularity is big, stress is big, easily cracks.

For solving the casting billet surface defect problem, it is imperative that crystallizer is improved.Two pieces of the relevant papers of being found in the recent period, one piece is that strong grade of well delivered in the Japan, " the Even cast solidifies Shell and forms To お I ほ The casting mold slow cooling shadow Ring ", iron と Steel, Vol.73, No.3,1987,498～504.This article has been introduced a kind of slow cooling groove crystallizer, and at crystallizer inwall delineation groove, width is 0.9mm between its two groove, and groove width is 0.8mm.Compare with traditional crystallizer, the air gap ratio increases between strand and crystallizer inwall, and strand initial stage solidification and heat transfer hot-fluid reduces, and conducts heat evenly, reduces slab surface crack.One piece is grand second-class the delivering in Japanese mountain pass, " the ステ Application レス Steel initial stage heterogeneity system of solidifying is driven ", the iron Steel initial stage solidifies, and Japanese iron Steel learns, and 1994.11,84～87.In the continuous casting simulated test of laboratory, the metallic nickel grid of plating thick 1mm, wide 5mm on crystallizer surface, mesh spacing is 2,10,15, and is identical with Article paper slow cooling effect during network spacing 10mm cc test.More than because groove broad, spacing are bigger, all be slow cooling type crystallizer.Shortcoming is because to be the slow cooling meeting exert an influence to the casting speed of conticaster.Groove or grid directly contact not wear-resistingly with strand in addition, will lose due effect after the wearing and tearing, and the crystallizer life-span are low.Therefore still need crystallizer is done further improvement.

Summary of the invention the object of the present invention is to provide a kind of coating trench wall crystallizer, and the initial solidification shell thickness that molten steel is formed in continuous cast mold is even, reduces slab surface crack, reduces the useless brilliant rate of strand, improves the strand pulling rate, prolongs the crystallizer life-span.

Purpose of the present invention realizes by following content:

Delineate on the inwall of continuous cast mold that 1～100 μ m is wide, 1～500 μ m is dark vertically or in length and breadth to fine groove, and add the plating wearing layer.

By above measure, initial solidification shell is cooled off the volume contraction distortion in the whole zone of crystallizer, be divided into and solidify the contraction distortion of cooling volume between groove, and the initial solidification shell heat transfer condition is identical between each groove, it is identical that promptly the base shell solidifies the contraction distortion of cooling volume.According to casting blank cross-section size, i.e. continuous cast mold inwall size, select delineation vertically or in length and breadth to groove fineness and groove number, i.e. width between two grooves.

The groove of continuous cast mold inwall adopts laser grooving and scribing.

The spacing of continuous cast mold inner wall trench is 0.01～2mm.

The present invention is by changing the size of continuous cast mold inner wall trench, make initial solidification shell solidify the cooling volume contraction in a big zone, be divided in some very little zones and solidify the cooling volume contraction, the initial solidification shell heat transfer condition is even, shell thickness is even, reduces slab surface crack.Conduct heat the inhomogeneity while improving initial solidification shell, also can reduce the air gap ratio between initial solidification shell and crystallizer, improved the two conductive heat flow, accelerate cooling velocity, can improve the strand pulling rate.Also improved continuous casting installation for casting productivity ratio and casting blank surface temperature, and helped energy-conservation.

By the wearing layer that plating adds, make that strand contacts friction in the casting process with wearing layer, before wearing layer was rubbed, the groove of crystallizer inwall delineation distributed and does not change the service life that can improve continuous casting trench wall crystallizer.

Description of drawings Fig. 1 is a Crytallizer for inner wall of continuous casting coated groove inwall schematic diagram; Fig. 2 is that the crystallizer inwall is in length and breadth to the fine groove front schematic view; Fig. 3 is that the crystallizer inwall is in length and breadth to the fine groove side schematic view.

The specific embodiment is shown in accompanying drawing 1,2,3, on continuous cast mold broadside cooling wall inwall 1 and narrow limit cooling wall inwall 2, use laser grooving and scribing 0.05mm wide respectively, 0.1mm dark lateral trench and longitudinal groove, groove pitch are 1mm, form the square net shape.Plate one deck wearing layer more then on broadside cooling wall inwall 1 and narrow limit cooling wall inwall 2, the wearing layer material is a chromium.

Claims

1, a kind of continuous cast mold is characterized in that delineating on the inwall of continuous cast mold that 1～500 μ m is wide, 1～100 μ m is dark vertically or in length and breadth to fine groove, and adds the plating wearing layer.

2, the described continuous cast mold of claim 1 is characterized in that the groove of continuous cast mold inwall adopts laser grooving and scribing, and the spacing of continuous cast mold inner wall trench is 0.01～2mm.