Continuous lubricating crystallizer for aluminum alloy semi-continuous casting
Technical field
The present invention relates to crystallizer for semi-continuous casting of aluminum alloy, be specifically related to aluminum alloy semi-continuous casting Castor Oil crystallizer, belong to the aluminum alloy semi-continuous casting technical field.
Background technology
In the aluminum alloy semi-continuous casting process, the heat transfer of crystallizer sidewall has significant effects to the aluminium alloy slab surface quality.In traditional semicontinuous casting technique, crystallizer often adopts copper alloy to process, copper inwall directly contacts with the liquid aluminium alloy melt in the casting process, resistance of billet withdrawal is big, usually the mode by artificial coating lubricating oil realizes smooth throwing, therefore the surface quality of ingot casting is relatively poor, needs bigger turning amount could satisfy the requirement of subsequent thermal distortion.The multiple advanced casting technique of improving the aluminium alloy cast ingot surface quality is arranged at present, comprise electromagnetic casting technology, hot direct casting technology for making, sliding (air curtain) foundry engieering of gas, low liquid level foundry engieering etc.
The electromagnetic casting technology can be produced the aluminum alloy round ingot and the slab ingot of surface-brightening, but the equipment investment of this technology is big, equipment is complicated, Operation and Maintenance requires height, and can not realize multimode production, so this technology only obtains small-scale application in industrial production.Hot direct casting technology for making is since the eighties of last century appearance seventies, because it has realized stable short mould casting and same level casting, the surface quality and the production efficiency of ingot casting all increase substantially, and therefore, this technology has obtained extensive use in aluminium alloy enterprise.Yet hot direct casting technology for making needs the operator to have skilled operating technology, and ingot casting can produce distinctive bridging type and sweat shape blemish when bad when technological parameter is regulated.
Sliding (air curtain) foundry engieering of gas is the extension of aluminum alloy heat direct casting technology for making, it is to have increased oil gas lubricating system on the basis that hot direct casting is made, when reducing ingot casting and crystallizer inwall frictional force, reduce an intensity of cooling of ingot casting, thereby improved the surface quality of aluminium alloy cast ingot.Sliding (air curtain) foundry engieering of gas can improve the surface quality of aluminium alloy cast ingot significantly, generally is used for pole production.But, sliding (air curtain) structure of mould more complicated of gas, that does not still have autonomous Design at present is applied to business-like this type of crystallizer and relevant device.
Low liquid level foundry engieering is the novel aluminum alloy foundry engieering of western developed country in the eighties of last century development nineties, the method that this technology does not adopt the one hot direct casting of traditional hot top to make, but inlay one deck graphite cake at traditional crystallizer inwall, graphite cake adopts continuous infiltration type lubricated.Casting process adopts the height of the accurate crystallization control device of tank level control system inner metal liquid face.Adopt ingot blank surface-brightening that this technology produces, smooth, even the surface quality of some ingot casting can match in excellence or beauty with no mould electromagnetic casting.But the equipment price of low liquid level foundry engieering is very expensive, and strict to the requirement of control system, mold structure and design are in confidential state.
Summary of the invention
At problems such as the advanced casting crystallizer complex structure of existing aluminium alloy, apparatus expensive, the invention provides a kind of advanced person's the real feasible continuous lubricating crystallizer that can increase substantially the aluminium alloy cast ingot surface quality, be applicable to the casting of aluminum alloy round ingot and slab ingot.
Purpose of the present invention is achieved through the following technical solutions:
Continuous lubricating crystallizer for aluminum alloy semi-continuous casting, comprise crystallizer body and loam cake, the inwall of crystallizer is inlaid with the graphite liner, characteristics are: be provided with independently oil pocket in loam cake, described graphite liner is up and down symmetrical structure and has tapering, the crystallizer body is provided with two independent water cavities up and down, be upper water cavity and following water cavity, upper water cavity has independently water inlet, also have independently water inlet on the following water cavity, water fender is installed in the upper water cavity, in the following water cavity water fender is installed also, establishes row's hole for water spraying in the bottom of upper water cavity, also establish row's hole for water spraying in the bottom of following water cavity, the angle of the angle of upper water cavity hole for water spraying and following water cavity hole for water spraying is inconsistent, is staggered.
Further, above-mentioned continuous lubricating crystallizer for aluminum alloy semi-continuous casting, the graphite liner has tapering, and its cone angle scope is at 174 °~179 °.
Further, above-mentioned continuous lubricating crystallizer for aluminum alloy semi-continuous casting, the angular range of upper water cavity hole for water spraying are at 15 °~35 °, and following water cavity hole for water spraying angular range is at 40 °~60 °.
Substantive distinguishing features and obvious improvement that technical solution of the present invention is outstanding are mainly reflected in:
1. the loam cake of crystallizer is established independent oil pocket, in casting process, keep the aluminium alloy melt liquid level below graphite liner center line, the high-strength graphite inner lining surface itself is difficult for being melted wetting metal, has self-lubricating property, in addition, the oil pocket of crystallizer upper wall forms the continuous oil film of one deck continuously to graphite inwall oil impregnate between graphite and melt, reduced an intensity of cooling of ingot casting when increasing lubricant effect; The liquid level of melt in crystallizer is lower during casting, excursion 6~15mm, and when reducing ingot casting and once cooling off, ingot surface quality has also obtained increasing substantially;
2. the graphite liner has taper design, can reduce the contact friction force of aluminium alloy melt and graphite in the casting process; The graphite liner adopts symmetric design up and down, the upset of graphite liner can be continued to use during wearing and tearing, has prolonged the service life of graphite liner;
3. the crystallizer body adopts independently two water cavity designs, can adopt a water cavity water supply or two water cavities to supply water simultaneously during casting as required.When two water cavities supplied water simultaneously, following water cavity cooling water impacted the splash (reflection splash) of ingot casting surface formation and can most ofly be eliminated by the cooling water of upper water cavity, and the secondary cooling effect of ingot casting obviously strengthens.
4. compare with the advanced casting crystallizer of existing aluminium alloy, mold structure novelty of the present invention, equipment cost are little, are applicable to the casting of aluminum alloy round ingot and slab ingot, have fabulous application value.
Description of drawings
Below in conjunction with accompanying drawing technical solution of the present invention is described further:
Fig. 1: the structural representation of continuous lubricating crystallizer of the present invention;
Fig. 2: the schematic diagram when continuous lubricating crystallizer of the present invention is used.
The implication of each Reference numeral sees the following form among the figure:
Reference numeral |
Implication |
Reference numeral |
Implication |
Reference numeral | Implication | |
1 |
Upper water cavity |
2 |
Following water cavity |
3 |
Oil pocket |
4 |
The graphite liner |
5 |
Loam cake |
61 |
The upper water cavity water fender |
62 |
Following water cavity water fender |
71 |
The upper water cavity water inlet |
72 |
Following water cavity water inlet |
Reference numeral |
Implication |
Reference numeral |
Implication |
Reference numeral | Implication | |
8 |
The crystallizer body |
9 |
The upper water cavity apopore |
10 |
Following water cavity apopore |
11 |
Lower cover |
12 |
Melt liquid level |
13 |
Melt |
14 |
Mushy Zone |
15 |
Ingot casting |
16 |
Oil film |
17 |
Cooling water |
18 |
Base |
|
|
The specific embodiment
As shown in Figure 1, continuous lubricating crystallizer for aluminum alloy semi-continuous casting comprises crystallizer body 8, loam cake 5 and lower cover 11; The inwall of crystallizer is inlaid with graphite liner 4, is provided with independently oil pocket 3 in loam cake 5, and graphite liner 4 is up and down symmetrical structure and has tapering, and its cone angle scope is at 174 °~179 °; Crystallizer body 8 is provided with two independent water cavities up and down, be upper water cavity 1 and following water cavity 2, have independently water inlet 71 on the upper water cavity 1, have independently water inlet 72 on the following water cavity 2, water fender 61 is installed in the upper water cavity 1, in the following water cavity 2 water fender 62 is installed, establish row's hole for water spraying 9 in the bottom of upper water cavity 1, the angular range of hole for water spraying 9 is at 15 °~35 °, establish row's hole for water spraying 10 in the bottom of following water cavity 2, hole for water spraying 10 angular ranges are at 40 °~60 °, and the inconsistent formation of angle of the angle of hole for water spraying 9 and hole for water spraying 10 is staggered.
The loam cake 5 of crystallizer designs an independently oil pocket 3, and oil pocket increases the lubricant effect of crystallizer to graphite liner 4 continuous, automatic oil impregnates during casting.Graphite liner 4 adopts casting high-strength and high ductility graphite, and graphite liner 4 employing taper design, cone angle scope are at 174 °~179 °, can reduce the contact friction force of aluminium alloy melt and graphite in the casting process.Graphite liner 4 adopts symmetric design up and down, the graphite upset can be continued to use when following graphite weares and teares owing to the casting overlong time, and the service life of graphite, comparable employing asymmetric design prolonged one times.
Two independent water cavities about the interior setting of crystallizer body are respectively upper water cavity 1 and lean on two independently water inlet pipe water supply respectively with 2, two water cavities of following water cavity, and realization difference or while supply water to ingot casting.Be separately installed with water fender in two water cavities, with the cooling water in two water cavities of even distribution.At the inconsistent hole for water spraying of the bottom of two water cavities staggered designs two row's angles, when two water cavities supply water simultaneously, following water cavity cooling water impacts the splash (reflection splash) of ingot casting surface formation and can most ofly be eliminated by the cooling water of upper water cavity, and the secondary cooling effect of ingot casting strengthens.
During aluminum alloy semi-continuous casting,, at first open crystallizer upper oil chamber 3, continuously, oil impregnate in crystallizer equably, make graphite liner 4 surfaces form the uniform oil films 16 of skims as Fig. 2; Aluminium alloy melt 13 at first is full of the inner chamber that is formed by base 18 and graphite after entering crystallizer, and under a cooling effect of base 18 and graphite liner 4 solidification forming.Because metal bath does not have relative stronger graphite with the capacity of heat transmission directly to contact, but across one deck oil film, so an intensity of cooling of melt reduces greatly.Base 18 beginnings move down with certain speed when melt liquid level in the crystallizer 12 rises near graphite liner center line, the ingot casting of partial coagulation is subjected to the secondary cooling effect of the cooling water of shock surface at a certain angle after throwing off crystallizer, strong heat exchange takes place in ingot casting 15 and cooling water 17, the complete gradually solidification forming of whole ingot casting.In the casting process, the liquid level scope of metal bath in crystallizer is 6~15mm.
The aluminum alloy casting technique difference of the different trades mark.In the casting incipient stage, for than the duralumin, hard alumin ium alloy that is easier to ftracture, as 2 * * * and 7 * * *, can select only to open upper water cavity 1, reduce the secondary intensity of cooling of ingot casting, after entering the stabilization sub stage, opens on ingot casting water cavity 2 down again, realizes two water cavities water supply.And for the preferable aluminium alloy of casting character, as 1 * * * and 3 * * *, then can promptly open two water cavities, water supply when realizing two water cavities in the incipient stage of casting.Compare with traditional conventional crystallizer, two water cavities of this crystallizer supply water simultaneously, and cooling water strengthens the heat exchange effect of ingot casting and cooling water, increase secondary intensity of cooling in " reflection splash " that the ingot casting surface forms in the time of can avoiding being supplied water by single water cavity.Under the prerequisite that the secondary intensity of cooling strengthens, the pattern in ingot casting liquid cave is more level and smooth, even can guarantee that the bleedout phenomenon does not take place yet to have lower melt liquid level in the crystallizer.
In sum, continuous by oil pocket in the semi-continuous casting process of aluminium alloy to the graphite liner, even oil impregnate, form one deck continuous oil film at graphite surface, when increasing the graphite lubrication effect, play heat insulation, reduce the effect that ingot casting once cools off, independently water cavity can be according to the as-cast property independent regulation of different aluminum alloys in casting process for two in crystallizer simultaneously, realize that independent or two water cavities supply water simultaneously, guaranteeing that the aluminium alloy cast ingot initial stage do not take place to increase the secondary cooling effect under the prerequisite of fire check, realize the low liquid level of crystallizer inside, liquid level is at 6~15mm, thereby greatly improve the surface quality of aluminium alloy cast ingot, brought fabulous technical meaning and remarkable economical effect to production.
Below only be concrete exemplary applications of the present invention, protection scope of the present invention is not constituted any limitation.All employing equivalents or equivalence are replaced and the technical scheme of formation, all drop within the rights protection scope of the present invention.