CN109485390A - A kind of ladle magnesian ramming mass and its preparation, application method - Google Patents

A kind of ladle magnesian ramming mass and its preparation, application method Download PDF

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Publication number
CN109485390A
CN109485390A CN201811629388.6A CN201811629388A CN109485390A CN 109485390 A CN109485390 A CN 109485390A CN 201811629388 A CN201811629388 A CN 201811629388A CN 109485390 A CN109485390 A CN 109485390A
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China
Prior art keywords
ramming
weight
ramming mass
ladle
parts
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Pending
Application number
CN201811629388.6A
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Chinese (zh)
Inventor
张义先
金钊
耿贺贺
尹斌
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Haicheng Lear Meg Materials Co Ltd Sita
HAICHENG ZHONGXING MAGNESIA SYNTHETIC MATERIALS CO Ltd
Original Assignee
Haicheng Lear Meg Materials Co Ltd Sita
HAICHENG ZHONGXING MAGNESIA SYNTHETIC MATERIALS CO Ltd
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Priority to CN201811629388.6A priority Critical patent/CN109485390A/en
Publication of CN109485390A publication Critical patent/CN109485390A/en
Pending legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/03—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite
    • C04B35/04—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite based on magnesium oxide
    • C04B35/043—Refractories from grain sized mixtures
    • C04B35/047—Refractories from grain sized mixtures containing chromium oxide or chrome ore
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/34—Non-metal oxides, non-metal mixed oxides, or salts thereof that form the non-metal oxides upon heating, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3409—Boron oxide, borates, boric acids, or oxide forming salts thereof, e.g. borax
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5427—Particle size related information expressed by the size of the particles or aggregates thereof millimeter or submillimeter sized, i.e. larger than 0,1 mm
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5436—Particle size related information expressed by the size of the particles or aggregates thereof micrometer sized, i.e. from 1 to 100 micron
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
    • C04B2235/9607—Thermal properties, e.g. thermal expansion coefficient
    • C04B2235/9615—Linear firing shrinkage

Abstract

The present invention relates to a kind of ladle magnesian ramming mass and its preparation, application method, the magnesian ramming mass uses magnesia for primary raw material, is made, the ratio of each component is using boric acid and chromic anhybride by agglutinant: 90~98 parts by weight of magnesia；0.3~1.5 parts by weight of boric acid, 1.0~3.0 parts by weight of chromic anhybride；The chemical component of magnesian ramming mass finished product is by weight percentage are as follows: MgO >=94%, Cr2O3 >=1.5%；End properties index are as follows: 3.5~6.0MPa of flexural strength after 1300 DEG C of burnings；1300 DEG C × 3h Linear change rate+0.2%~+1.0%.Magnesian ramming mass of the present invention is constructed for bottom of steel ladle gap, good integrity after construction, and has good fire resistance, intensity and volume stability, stable and reliable in work, prepares, is easy for construction, at low cost.

Description

A kind of ladle magnesian ramming mass and its preparation, application method
Technical field
The present invention relates to technical field of refractory materials more particularly to a kind of ladle magnesian ramming mass and its preparations, use Method.
Background technique
Ladle is the capital equipment of STEELMAKING PRODUCTION, and existing three angular gaps often become ladle between containment wall brick and packet bottom brick The weak link of lining.For this purpose, we develop the good magnesian ramming mass of a kind of high temperature resistant, volume stability for filling up ladle lining Gap.
Summary of the invention
The present invention provides a kind of ladle magnesian ramming mass and its preparation, application method, which is used for steel The construction of packet bottom gap, good integrity after construction, and there is good fire resistance, intensity and volume stability, the operation is stable Reliably, it prepares, is easy for construction, it is at low cost.
In order to achieve the above object, the present invention is implemented with the following technical solutions:
A kind of ladle magnesian ramming mass, the magnesian ramming mass uses magnesia for primary raw material, with boric acid and chromic anhybride It is made, the ratio of each component is of agglutinant: 90~98 parts by weight of magnesia；0.3~1.5 parts by weight of boric acid, chromic anhybride 1.0~ 3.0 parts by weight；The chemical component of magnesian ramming mass finished product is by weight percentage are as follows: MgO >=94%, Cr2O3>=1.5%；At moral character Energy index are as follows: 3.5~6.0MPa of flexural strength after 1300 DEG C of burnings；1300 DEG C × 3h Linear change rate+0.2%~+1.0%.
The magnesia is magnesite clinker or fused magnesite, granularmetric composition are as follows: 1mm < granularity≤4mm, 45~55 parts by weight, 0.074mm < granularity≤1mm, 25~35 parts by weight；Granularity≤0.074mm, 12~40 parts by weight.
A kind of preparation method of ladle magnesian ramming mass, comprising: magnesia is processed respectively by granularmetric composition, will be added The magnesia of 3 kinds of good grades of work is uniformly mixed according to the proportion with boric acid, chromic anhybride Ji Wei finished product.
A kind of application method of ladle magnesian ramming mass, includes the following steps:
1) the sundries thorough cleaning especially wrapped the sundries in ladle in the gap of bottom is clean；
2) ramming mass of one layer of 80~110mm thickness is laid in the triangular slits of bottom of steel ladle, with ramming tool ramming, Until the ramming bed of material reaches the thickness of 55~85mm；
3) the ramming mass layer surface after tamping is subjected to hair pulling treatment, is connected conducive to it with subsequent the close of the ramming bed of material, Layering is avoided to influence globality；
4) the upper surface of first layer ramming bed of material be laid with second layer ramming mass, repeat step 2) -3) ramming and plucking at Reason process, until the top surface of the multilayer ramming bed of material is concordant with the upper surface of packet bottom brick.
Compared with prior art, the beneficial effects of the present invention are:
1) ladle is constructed with magnesian ramming mass for bottom of steel ladle gap, and work progress is simple, easy to operate；
2) after the ladle is constructed with magnesian ramming mass, globality is very good, and fire resistance, intensity and volume stability are all It is good, it is stable and reliable in work, obtain applications well effect；
3) ladle is cheap with magnesian ramming mass sorting, and preparation method is simple, expense is few, production cost compared with It is low.
Specific embodiment
A kind of ladle magnesian ramming mass of the present invention, the magnesian ramming mass uses magnesia for primary raw material, with boron Acid and chromic anhybride are made of agglutinant, the ratio of each component is: 90~98 parts by weight of magnesia；0.3~1.5 parts by weight of boric acid, chromium 1.0~3.0 parts by weight of acid anhydrides；The chemical component of magnesian ramming mass finished product is by weight percentage are as follows: MgO >=94%, Cr2O3≥ 1.5%；End properties index are as follows: 3.5~6.0MPa of flexural strength after 1300 DEG C of burnings；1300 DEG C × 3h Linear change rate+0.2%~ + 1.0%.
The magnesia is magnesite clinker or fused magnesite, granularmetric composition are as follows: 1mm < granularity≤4mm, 45~55 parts by weight, 0.074mm < granularity≤1mm, 25~35 parts by weight；Granularity≤0.074mm, 12~40 parts by weight.
A kind of preparation method of ladle magnesian ramming mass, comprising: magnesia is processed respectively by granularmetric composition, will be added The magnesia of 3 kinds of good grades of work is uniformly mixed according to the proportion with boric acid, chromic anhybride Ji Wei finished product.
A kind of application method of ladle magnesian ramming mass, includes the following steps:
1) the sundries thorough cleaning especially wrapped the sundries in ladle in the gap of bottom is clean；
2) ramming mass of one layer of 80~110mm thickness is laid in the triangular slits of bottom of steel ladle, with ramming tool ramming, Until the ramming bed of material reaches the thickness of 55~85mm；
3) the ramming mass layer surface after tamping is subjected to hair pulling treatment, is connected conducive to it with subsequent the close of the ramming bed of material, Layering is avoided to influence globality；
4) the upper surface of first layer ramming bed of material be laid with second layer ramming mass, repeat step 2) -3) ramming and plucking at Reason process, until the top surface of the multilayer ramming bed of material is concordant with the upper surface of packet bottom brick.
Following embodiment is implemented under the premise of the technical scheme of the present invention, gives detailed embodiment and tool The operating process of body, but protection scope of the present invention is not limited to following embodiments.Method therefor is such as without spy in following embodiments Not mentionleting alone bright is conventional method.
[embodiment 1]
In the present embodiment, ladle is made with magnesian ramming mass of following raw materials ratio by weight: 95 98 parts of medium-grade magnesites, 0.7 part of boric acid, 1.5 parts of powdery chromic anhybride.
Magnesia is processed respectively by granularmetric composition, the magnesia proportion of 3 kinds of grades are as follows: 1mm < granularity≤4mm, 47 weights Measure part, 0.074mm < granularity≤1mm, 28 parts by weight；Granularity≤0.074mm, 35 parts by weight press magnesia and boric acid, chromic anhybride Be uniformly mixed according to proportion is finished product.
The chemical component of magnesian ramming mass finished product is by weight percentage are as follows: MgO 94.3%, Cr2O31.65%；At moral character Energy index are as follows: flexural strength 5.61MPa after 1300 DEG C of burnings；1300 DEG C × 3h Linear change rate+1.24%.
[embodiment 2]
In the present embodiment, ladle is made with magnesian ramming mass of following raw materials ratio by weight: 97 94 parts of highly-purity magnesites, 1.1 parts of boric acid, 2.6 parts of powdery chromic anhybride.
Magnesia is processed respectively by granularmetric composition, the magnesia proportion of 3 kinds of grades are as follows: 1mm < granularity≤4mm, 53 weights Measure part, 0.074mm < granularity≤1mm, 32 parts by weight；Granularity≤0.074mm, 26 parts by weight press magnesia and boric acid, chromic anhybride Be uniformly mixed according to proportion is finished product.
The chemical component of magnesian ramming mass finished product is by weight percentage are as follows: MgO 94.5%, Cr2O31.59%；At moral character Energy index are as follows: flexural strength 4.97MPa after 1300 DEG C of burnings；1300 DEG C × 3h Linear change rate+1.38%.
[embodiment 3]
In the present embodiment, ladle is made with magnesian ramming mass of following raw materials ratio by weight: 97 92 parts of fused magnesites, 0.8 part of boric acid, 1.5 parts of powdery chromic anhybride.
Magnesia is processed respectively by granularmetric composition, the magnesia proportion of 3 kinds of grades are as follows: 1mm < granularity≤4mm, 47 weights Measure part, 0.074mm < granularity≤1mm, 29 parts by weight；Granularity≤0.074mm, 31 parts by weight press magnesia and boric acid, chromic anhybride Be uniformly mixed according to proportion is finished product.
The chemical component of magnesian ramming mass finished product is by weight percentage are as follows: MgO 94.6%, Cr2O31.58%；At moral character Energy index are as follows: flexural strength 4.38MPa after 1300 DEG C of burnings；1300 DEG C × 3h Linear change rate+1.36%.
The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto, Anyone skilled in the art in the technical scope disclosed by the present invention, according to the technique and scheme of the present invention and its Inventive concept is subject to equivalent substitution or change, should be covered by the protection scope of the present invention.

Claims (4)

1. a kind of ladle magnesian ramming mass, which is characterized in that the magnesian ramming mass uses magnesia for primary raw material, with boric acid It is made, the ratio of each component is of agglutinant with chromic anhybride: 90~98 parts by weight of magnesia；0.3~1.5 parts by weight of boric acid, chromic acid 1.0~3.0 parts by weight of acid anhydride；The chemical component of magnesian ramming mass finished product is by weight percentage are as follows: MgO >=94%, Cr2O3≥ 1.5%；End properties index are as follows: 3.5~6.0MPa of flexural strength after 1300 DEG C of burnings；1300 DEG C × 3h Linear change rate+0.2%~ + 1.0%.
2. a kind of ladle magnesian ramming mass according to claim 1, which is characterized in that the magnesia be magnesite clinker or Fused magnesite, granularmetric composition are as follows: 1mm < granularity≤4mm, 45~55 parts by weight, 0.074mm < granularity≤1mm, 25~35 weight Part；Granularity≤0.074mm, 12~40 parts by weight.
3. a kind of preparation method of ladle magnesian ramming mass as described in claim 1 characterized by comprising by magnesia It is processed respectively by granularmetric composition, the magnesia of process 3 kinds of grades is uniformly mixed i.e. according to the proportion with boric acid, chromic anhybride For finished product.
4. a kind of application method of ladle magnesian ramming mass as described in claim 1, which is characterized in that including walking as follows It is rapid:
1) the sundries thorough cleaning especially wrapped the sundries in ladle in the gap of bottom is clean；
2) ramming mass of one layer of 80~110mm thickness is laid in the triangular slits of bottom of steel ladle, with ramming tool ramming, until The ramming bed of material reaches the thickness of 55~85mm；
3) the ramming mass layer surface after tamping is subjected to hair pulling treatment, is connected conducive to it with subsequent the close of the ramming bed of material, avoids Layering influences globality；
4) the upper surface of first layer ramming bed of material be laid with second layer ramming mass, repeat step 2) -3) ramming and hair pulling treatment mistake Journey, until the top surface of the multilayer ramming bed of material is concordant with the upper surface of packet bottom brick.
CN201811629388.6A 2018-12-29 2018-12-29 A kind of ladle magnesian ramming mass and its preparation, application method Pending CN109485390A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112876266A (en) * 2021-03-19 2021-06-01 湖南宝峰炉料有限公司 Continuous casting tundish dry ramming material and preparation method and application thereof

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1062335A (en) * 1991-05-28 1992-07-01 冶金工业部辽宁镁矿公司 A kind of magnesian ramming mass and manufacture method thereof
CN102391003A (en) * 2011-08-05 2012-03-28 海城市中兴镁质合成材料有限公司 MgO-Cr2O3 ramming material for VOD (Vacuum Oxygen Decarburization) steel ladle safety liner

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1062335A (en) * 1991-05-28 1992-07-01 冶金工业部辽宁镁矿公司 A kind of magnesian ramming mass and manufacture method thereof
CN102391003A (en) * 2011-08-05 2012-03-28 海城市中兴镁质合成材料有限公司 MgO-Cr2O3 ramming material for VOD (Vacuum Oxygen Decarburization) steel ladle safety liner

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
朱洪法: "《催化剂手册》", 31 August 2008 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112876266A (en) * 2021-03-19 2021-06-01 湖南宝峰炉料有限公司 Continuous casting tundish dry ramming material and preparation method and application thereof

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Address after: 114206 Bali Town wangjiakan village, Haicheng City, Anshan City, Liaoning Province

Applicant after: Liaoning lier magnesium synthetic material Co.,Ltd.

Applicant after: HAICHENG LIER MAIGE XITA MATERIAL Co.,Ltd.

Address before: 114206 Bali Town wangjiakan village, Haicheng City, Anshan City, Liaoning Province

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Application publication date: 20190319