YB/T 5011-2014 镁铬砖/Magnesia-chrome brick
镁铬砖
1.范围
本标准规定了镁铬砖的分类、技术要求、试验方法、质量评定程序、包装、标志、运输、储存及质量证明书。
本标准适用于有色冶炼炉、炼钢精炼炉、水泥回转窑等工业窑炉用烧成镁铬砖。
2.规范性引用文件
下列文件对于本文件的应用是必不可少的。凡是注日期的引用文件,仅所注日期的版本适用于本文件。凡是不注日期的引用文件，其最新版本(包括所有的修改单)适用于本文件。
GB/T 2992.1 耐火砖形状尺寸第1部分通用砖。
GB/T 2997致密定形耐火制品体积密度、显气孔率和真气孔率试验方法。
GB/T 5070含铬耐火材料化学分析方法。
GB/T 5072耐火材料 常温耐压强度试验方法。
GB/T 7321定形耐火制品试样制备方法。
GB/T 10325定形耐火制品验收抽样检验规则。
GB/T 10326定形耐火制品尺寸、外观及断面的检在方法。
GB/T 16546定形耐火制品包装、标志、运输和储存。
GB/T 17912回转密用耐火砖形状尺寸。
GB/T 18257回转窑用耐火砖热面标记。
GB/T 20511耐火制品分型规则。
YB/T 370耐火制品荷重软化温度试验方法(非示差–升温法)。
YB/T 376.1耐火制品抗热震性试验方法(水急冷法)。
YB/T 376.2耐火制品抗热震性试验方法(空气急冷法)。
3.术语和定义
GB/T 10325界定的以及下列术语和定适用于本文件
3.1直接结合镁铬砖（direct bonded magnesia chrome bricks）
是指以高纯度镁砂和铬精矿为主要原料制成的耐火制品。
3 3电熔再结合镁铭砖 fused rebonded magnesia chrome bricks）
是指以电熔镁铬砂为主要原料制成的耐火制品。
3.4电熔半再结合镁铬砖（fused semi-rebonded magnesia chrome bricks）
是指以电熔镁铬砂和烧结镁砂、铭铁矿或者预反应镁铬砂制成的耐火制品。
3.5普通镁铭砖（common mapnesia chrome bricks）
是指以普通镁砂和一般耐火级铬矿为原料制成的耐火制品。
4.分类和形状尺寸
4.1 砖按所用原料分为直接结合镁铬砖、电熔再结合镁砖、电熔半再结合镁铭砖、普通镁铬砖四类,按Cr2O3含量不同,直接结合镁砖分为7个牌号;电熔再结合镁砖分为 9 个牌号;电熔半再结合镁铬砖分为 10个牌号;普通镁铬砖分为6个牌号。
其中短横线前面的字母Z、D、B、M分别为直接结合电熔再结合、半再结合、镁砖首个汉字拼音的首个字母的大写字母,Ge为铬的拼音;数字后面的字母AB分别代表同一路含量的不同级别。
4.2砖的形状尺寸应符合GB/T 2992.1GB/T 20511GB/T 17912的规定,亦可按需方提供的图纸进行生产。
5技术要求
5.1砖的理化指标应符合表1、表2、表3和表4的规定。
5.2砖的尺寸允许偏差和外观应符合表5的规定。
5.3手工砖及其他特殊要求由供需双方协商确定。
| 表 1 直接结合镁铬砖的理化指标 |
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| 项目 | 指标 | |||||||
| ZMGe-16A | ZMGe-16B | ZMGe-12A | ZMGe-12B | ZMGe-8A | ZMGe-8B | ZMGe-6 | ||
| w(MgO)/% | μ0≥ | 60 | 58 | 68 | 65 | 75 | 70 | 75 |
| σ^ | 2.5 | |||||||
| w(Cr2O3)/% | μ0≥ | 16 | 16 | 12 | 12 | 8 | 8 | 8 |
| σ^ | 1.5 | |||||||
| w(SiO2)/% | μ0≤ | 1.5 | 2.5 | 1.5 | 2.5 | 1.5 | 2.5 | 2.5 |
| σ^ | 0.3 | |||||||
| 显气孔率/% | μ0≤ | 18 | 18 | 18 | 18 | 18 | 18 | 18 |
| σ^ | 1.5 | |||||||
| 常温耐压强度a/MPa | μ0≥ | 40 | 40 | 45 | 45 | 45 | 45 | 45 |
| xmin | 35 | 35 | 35 | 35 | 35 | 35 | 35 | |
| σ^ | 15 | |||||||
| 荷重软化温度/℃(0.2MPa,T0.6) | μ0≥ | 1700 | 1650 | 1700 | 1650 | 1700 | 1650 | 1700 |
| σ^ | 20 | |||||||
| 抗热震性/次 | 提供数据 | |||||||
| 注:抗热震性可根据用户需求进行检测。 耐压强度所测单值应均大于X规定值 |
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表 2 电熔再结合镁铬砖的理化指标 |
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|
项目 |
指 标 |
||||||||||||
|
DMGe-26 |
DMGe-24 |
DMGe-22 |
DMGe-20A |
DMGe-20B |
|||||||||
|
w(MgO)/% |
μ0≥ |
50 |
50 |
55 |
58 |
58 |
|||||||
|
σ^ |
2.5 |
||||||||||||
|
w(Cr2O3)/% |
μ0≥ |
26 |
24 |
22 |
20 |
20 |
|||||||
|
σ^ |
1.5 |
||||||||||||
|
w(SiO2)/% |
μ0≤ |
1.5 |
1.5 |
1.5 |
1.5 |
2.0 |
|||||||
|
σ^ |
0.3 |
||||||||||||
|
显气孔率/% |
μ0≤ |
16(15) |
16(15) |
16(15) |
16(15) |
17(15) |
|||||||
|
σ^ |
1.5 |
||||||||||||
|
常温耐压强度a/MPa |
μ0≥ |
40(45) |
40(45) |
40(45) |
40(45) |
40(45) |
|||||||
|
xmin |
35(40) |
35(40) |
35(40) |
35(40) |
35(40) |
||||||||
|
σ^ |
15 |
||||||||||||
|
荷重软化温度/℃(0.2MPa,T0.6) |
μ0≥ |
1700 |
1700 |
1700 |
1700 |
1700 |
|||||||
|
σ^ |
20 |
||||||||||||
|
抗热震性/次 |
提供数据 |
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|
项目 |
指 标 |
||||||||||||
|
DMGe-16A |
DMGe-16B |
DMGe-12A |
DMGe-12B |
||||||||||
|
w(MgO)/% |
μ0≥ |
62 |
58 |
68 |
65 |
||||||||
|
σ^ |
2.5 |
||||||||||||
|
w(Cr2O3)/% |
μ0≥ |
16 |
16 |
12 |
12 |
||||||||
|
σ^ |
1.5 |
||||||||||||
|
w(SiO2)/% |
μ0≤ |
1.5 |
2.0 |
1.5 |
2.0 |
||||||||
|
σ^ |
0.3 |
||||||||||||
|
显气孔率/% |
μ0≤ |
16(15) |
17(16) |
16(15) |
17(16) |
||||||||
|
σ^ |
1.5 |
||||||||||||
|
常温耐压强度a/MPa |
μ0≥ |
40(45) |
40(45) |
40(45) |
40(45) |
||||||||
|
xmin |
35(40) |
35(40) |
35(40) |
35(40) |
|||||||||
|
σ^ |
15 |
||||||||||||
|
荷重软化温度/℃(0.2MPa,T0.6) |
μ0≥ |
1700 |
1700 |
1700 |
1700 |
1700 |
|||||||
|
σ^ |
20 |
||||||||||||
|
抗热受性/次 |
提供数据 |
||||||||||||
|
注1:抗热展性可根据用户需求进行检测。 注2:括号内为没盐砖的数据。 |
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|
表3 电熔半再结合镁铬砖的理化指标 |
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|
项目 |
指 标 |
|||||||||||
|
BMGe-26 |
EMGe-24 |
BMGe-22 |
BMGe-20A |
BMGe-20B |
||||||||
|
w(MgO)/% |
μ0≥ |
50 |
50 |
55 |
58 |
55 |
||||||
|
σ^ |
2.5 |
|||||||||||
|
w(Cr2O3)/% |
μ0≥ |
26 |
24 |
22 |
20 |
20 |
||||||
|
σ^ |
1.5 |
|||||||||||
|
w(SiO2)/% |
μ0≤ |
2.0 |
2.0 |
2.0 |
2.0 |
2.5 |
||||||
|
σ^ |
0.3 |
|||||||||||
|
显气孔率/% |
μ0≤ |
16(15) |
16(15) |
16(15) |
16(15) |
16(15) |
||||||
|
σ^ |
1.5 |
|||||||||||
|
常温耐压强度a/MPa |
μ0≥ |
40(45) |
40(45) |
40(45) |
40(45) |
35(40) |
||||||
|
xmin |
35(40) |
35(40) |
35(40) |
35(40) |
30(35) |
|||||||
|
σ^ |
15 |
|||||||||||
|
荷重软化温度/℃(0.2MPa,T0.6) |
μ0≥ |
1700 |
1700 |
1700 |
1700 |
1700 |
||||||
|
σ^ |
20 |
|||||||||||
|
抗热震性/次 |
提供数据 |
|||||||||||
|
项目 |
指 标 |
|||||||||||
|
BMGe-18 |
BMGe-16A |
BMGe-16B |
BMGe-12A |
BMGe-12B |
||||||||
|
w(MgO)/% |
μ0≥ |
58 |
60 |
55 |
68 |
65 |
||||||
|
σ^ |
2.5 |
|||||||||||
|
w(Cr2O3)/% |
μ0≥ |
18 |
16 |
16 |
12 |
12 |
||||||
|
σ^ |
1.5 |
|||||||||||
|
w(SiO2)/% |
μ0≤ |
2.0 |
2.0 |
2.5 |
2.0 |
2.5 |
||||||
|
σ^ |
0.3 |
|||||||||||
|
显气孔率/% |
μ0≤ |
16(15) |
16(15) |
17(15) |
16(15) |
16(15) |
||||||
|
σ^ |
1.5 |
|||||||||||
|
常温耐压强度a/MPa |
μ0≥ |
40(45) |
40(45) |
35(40) |
40(45) |
35(40) |
||||||
|
xmin |
35(40) |
35(40) |
30(35) |
35(40) |
30(35) |
|||||||
|
σ^ |
15 |
|||||||||||
|
荷重软化温度/℃(0.2MPa,T0.6) |
μ0≥ |
1700 |
1700 |
1700 |
1700 |
1700 |
||||||
|
σ^ |
20 |
|||||||||||
|
抗热受性/次 |
提供数据 |
|||||||||||
|
注1:抗热震性可根据用户需求进行检测。 注2:括号内为没盐砖的数据。 |
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|
表4普通镁铬砖的理化指标 |
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|
项目 |
指 标 |
||||||
|
MGe-16A |
MGe-16B |
MGe-12A |
MGe-12B |
MGe-8A |
MGe-8B |
||
|
w(MgO)/% |
μ0≥ |
50 |
45 |
60 |
55 |
65 |
60 |
|
σ^ |
2.5 |
||||||
|
w(Cr2O3)/% |
μ0≥ |
16 |
16 |
12 |
12 |
8 |
8 |
|
σ^ |
1.5 |
||||||
|
显气孔率/% |
μ0≤ |
19 |
22 |
19 |
21 |
19 |
21 |
|
σ^ |
1.5 |
||||||
|
常温耐压强度a/MPa |
μ0≥ |
35 |
25 |
35 |
30 |
35 |
30 |
|
xmin |
30 |
20 |
30 |
25 |
30 |
25 |
|
|
σ^ |
15 |
||||||
|
荷重软化温度/℃(0.2MPa,T0.6) |
μ0≥ |
1650 |
1550 |
1650 |
1550 |
1650 |
1530 |
|
σ^ |
20 |
||||||
|
耐压强度所测单值应均大于Xmin规定值。 |
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|
表5 砖的尺寸允许偏差及外观 |
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|
项 目 |
指 标 |
|||
|
尺寸允许偏差 |
加工面 |
±0.5 |
||
|
尺寸≤200 |
±1.5 |
|||
|
尺寸201-300 |
士3.0 |
|||
|
尺寸>300 |
士4.0 |
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|
扭曲 |
加工面 |
0.5 |
||
|
长度≤350 |
1.5 |
|||
|
长度>350 |
2.0 |
|||
|
缺角长度(a+b+c) |
工作面 |
40 |
||
|
非工作面 |
60 |
|||
|
缺棱长度(e+f+g) |
工作面 |
50 |
||
|
非工作面 |
70 |
|||
|
裂纹长度 |
宽度≤0.10 |
不限制 |
||
|
宽度 0.11~0.25 |
工作面 |
50 |
||
|
非工作面 |
80 |
|||
|
宽度 0.26~0.5 |
工作面 |
30 |
||
|
非工作面 |
50 |
|||
|
宽度>0.5 |
不准有 |
|||
|
厚度相对边差 |
1.0 |
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|
注1:缺棱缺角数量:工作面≤2，非工作面≤3，每块砖总计<3 注2:裂纹跨棱时只允许跨过一条棱,跨棱裂纹合并计算。 |
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6.试验方法
6.1砖的检验制样按 GB/T 7321进行。
6.2化学分析按 GB/T 5070进行。
6.3显气孔率的检验按 GB/T 2997进行。
6.4常温耐压强度的检验按 GB/T 5072进行。
6.5荷重软化温度的检验按 YB/T 370进行。
6.6抗热熊性的检验按 YB/T 376.1或YB/T 376.2进行。
6.7砖的尺寸、外观及断面的检查按 GB/T 10326进行
7质量评定程序。
7.1组批
产品按同一牌号编批,每批不大于300t。
7.2抽样及合格判定规则
砖的抽样、验收按 GB/T 10325进行。化学成分、显气孔率、重软化温度、常温耐压强度为验收检验项目。
7.3 合格评定形式
合格评定可采用供货方声明、使用方认定或第三方认证的形式进行。
8包装、标志、运输、储存及质量证明书
8.1砖采用托盘或根据用户要求进行包装。
8.2砖的运输和储存按 GB/T 16546规定进行。
8.3回转密用耐火砖热面标记应符合 GB/T 18257的规定,亦可按需方提供的图纸或要求进行标记。
8.4砖发出时应附有供方质量部门签发的质量证明书,质量证明书应载明供方名称或广标、方名称发货日期、合同号、标准编号、产品名称、牌号、砖号、批号及相应的理化检验结果。
Magnesia-chrome brick
1.Scope
This standard specifies the classification, technical requirements, test methods, quality assessment procedures, packaging, marking, transportation, storage and quality certificates of magnesia-chrome bricks.
This standard is applicable to fired magnesium-chrome bricks for industrial kilns such as non-ferrous smelting furnaces, steel refining furnaces and cement rotary kilns.
2.Normative reference documents
The following documents are essential for the application of this document. For dated references, only the dated version applies to this document. For undated references, the latest version (including all amendment orders) applies to this document.
GB/T 2992.1 Shape and dimensions of refractory bricks – Part 1 – General purpose bricks.
Test method for bulk density, apparent porosity and true porosity of GB/T 2997 compact shaped refractory products.
GB/T 5070 chromium containing refractory chemical analysis method.
GB/T 5072 refractories – normal temperature compressive strength test method.
GB/T 7321 shaped refractory product sample preparation method.
GB/T 10325 shaped refractory products acceptance sampling inspection rules.
GB/T 10326 shaped refractory products size, appearance and section inspection method.
GB/T 16546 shaped refractory products packaging, marking, transportation and storage.
GB/T 17912 Shape and size of rotary close firebrick.
GB/T 18257 hot surface marking of refractory brick for rotary kiln.
GB/T 20511 classification rules for refractory products.
Test method for load softening temperature of YB/T 370 refractory products (non-differential – rising temperature method).
YB/T 376.1 Test method for thermal shock resistance of refractory products (water quench method).
YB/T 376.2 Test method for thermal shock resistance of refractory products (air quenching method).
3.Terms and definitions
As defined in GB/T 10325, the following terms and conditions shall apply to this document.
3.1 direct bonded magnesia chrome bricks
It refers to refractory products made of high purity magnesia and chromium concentrate as the main raw materials.
fused rebonded magnesia chrome bricks) Fused rebonded Magnesia Chrome bricks)
It refers to refractory products made of fused magnesia chrome sand as the main raw material.
3.4 fused semi-rebonded magnesia chrome bricks
It refers to the refractory products made of fused magnesia chrome sand and sintered magnesia, Ming iron ore or pre-reacted magnesia chrome sand.
3.5 common mapnesia chrome bricks
It refers to the refractory products made of ordinary magnesia and general refractory grade chromium ore as raw materials.
4.Classification and shape size
4.1 According to the raw materials used, the bricks can be divided into four categories: direct bonded magnesia chrome brick, electric fused rebonded magnesia brick, electric fused semi-recombined magnesia chrome brick and ordinary magnesia chrome brick. According to the different Cr2O3 content, direct bonded magnesia brick can be divided into 7 grades; Fused magnesia brick is divided into 9 grades; Electromelt semi-recombined magnesium-chrome brick is divided into 10 grades; Ordinary magnesia-chrome bricks are divided into 6 grades.
The letters Z, D, B and M in front of the short horizontal line are the uppercase letters of the first alphabetic letter of the first Chinese pinyin of the direct fusion recombination, semi-recombination, and magnesium brick respectively, and Ge is the pinyin of chromium; The letter AB after the number represents different levels of the same route content.
4.2 The shape and size of the bricks shall comply with the provisions of GB/T 2992.1GB/T 20511GB/T 17912, and can also be produced according to the drawings provided by the demander.
5 Technical Requirements
5.1 The physical and chemical indexes of bricks shall comply with the provisions of Tables 1, 2, 3 and 4.
5.2 The permissible size deviation and appearance of the brick shall comply with the provisions of Table 5.
5.3 Handmade bricks and other special requirements shall be determined by both parties through negotiation.
Table 1 Physicochemical indexes of directly bonded magnesia-chromium bricks
|
Table 1 Physicochemical indexes of directly bonded magnesia-chromium bricks |
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| Items | Indicators | |||||||
| ZMGe-16A | ZMGe-16B | ZMGe-12A | ZMGe-12B | ZMGe-8A | ZMGe-8B | ZMGe-6 | ||
| w(MgO)/% | μ0≥ | 60 | 58 | 68 | 65 | 75 | 70 | 75 |
| σ^ | 2.5 | |||||||
| w(Cr2O3)/% | μ0≥ | 16 | 16 | 12 | 12 | 8 | 8 | 8 |
| σ^ | 1.5 | |||||||
| w(SiO2)/% | μ0≤ | 1.5 | 2.5 | 1.5 | 2.5 | 1.5 | 2.5 | 2.5 |
| σ^ | 0.3 | |||||||
| Apparent porosity /% | μ0≤ | 18 | 18 | 18 | 18 | 18 | 18 | 18 |
| σ^ | 1.5 | |||||||
| Compressive strengtha /MPa at room temperature |
μ0≥ | 40 | 40 | 45 | 45 | 45 | 45 | 45 |
| xmin | 35 | 35 | 35 | 35 | 35 | 35 | 35 | |
| σ^ | 15 | |||||||
| Load softening temperature /℃(0.2MPa,T 0.6 ) |
μ0≥ | 1700 | 1650 | 1700 | 1650 | 1700 | 1650 | 1700 |
| σ^ | 20 | |||||||
| Thermal shock resistance/ti | Data provided | |||||||
| Note: Thermal shock resistance can be tested according to user requirements. The single value of compressive strength measured should be greater than the specified value of Xmin |
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|
Table 2 Physical and chemical indexes of electromelting rebonded magnesia-chrome brick |
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|
Items |
Indicators |
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|
DMGe-26 |
DMGe-24 |
DMGe-22 |
DMGe-20A |
DMGe-20B |
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|
w(MgO)/% |
μ0≥ |
50 |
50 |
55 |
58 |
58 |
||||||||||||||||||||||||||||||||
|
σ^ |
2.5 |
|||||||||||||||||||||||||||||||||||||
|
w(Cr2O3)/% |
μ0≥ |
26 |
24 |
22 |
20 |
20 |
||||||||||||||||||||||||||||||||
|
σ^ |
1.5 |
|||||||||||||||||||||||||||||||||||||
|
w(SiO2)/% |
μ0≤ |
1.5 |
1.5 |
1.5 |
1.5 |
2.0 |
||||||||||||||||||||||||||||||||
|
σ^ |
0.3 |
|||||||||||||||||||||||||||||||||||||
|
Apparent porosity /% |
μ0≤ |
16(15) |
16(15) |
16(15) |
16(15) |
17(15) |
||||||||||||||||||||||||||||||||
|
σ^ |
1.5 |
|||||||||||||||||||||||||||||||||||||
|
μ0≥ |
40(45) |
40(45) |
40(45) |
40(45) |
40(45) |
|||||||||||||||||||||||||||||||||
|
xmin |
35(40) |
35(40) |
35(40) |
35(40) |
35(40) |
|||||||||||||||||||||||||||||||||
|
σ^ |
15 |
|||||||||||||||||||||||||||||||||||||
|
Compressive strengtha /MPa at room temperature |
μ0≥ |
1700 |
1700 |
1700 |
1700 |
1700 |
||||||||||||||||||||||||||||||||
|
σ^ |
20 |
|||||||||||||||||||||||||||||||||||||
|
Thermal shock resistance/times |
Data provided |
|||||||||||||||||||||||||||||||||||||
|
Items |
Indicators |
|||||||||||||||||||||||||||||||||||||
|
DMGe-16A |
DMGe-16B |
DMGe-12A |
DMGe-12B |
|||||||||||||||||||||||||||||||||||
|
w(MgO)/% |
μ0≥ |
62 |
58 |
68 |
65 |
|||||||||||||||||||||||||||||||||
|
σ^ |
2.5 |
|||||||||||||||||||||||||||||||||||||
|
w(Cr2O3)/% |
μ0≥ |
16 |
16 |
12 |
12 |
|||||||||||||||||||||||||||||||||
|
σ^ |
1.5 |
|||||||||||||||||||||||||||||||||||||
|
w(SiO2)/% |
μ0≤ |
1.5 |
2.0 |
1.5 |
2.0 |
|||||||||||||||||||||||||||||||||
|
σ^ |
0.3 |
|||||||||||||||||||||||||||||||||||||
|
Apparent porosity /% |
μ0≤ |
16(15) |
17(16) |
16(15) |
17(16) |
|||||||||||||||||||||||||||||||||
|
σ^ |
1.5 |
|||||||||||||||||||||||||||||||||||||
|
Compressive strengtha /MPa at room temperature |
μ0≥ |
40(45) |
40(45) |
40(45) |
40(45) |
|||||||||||||||||||||||||||||||||
|
xmin |
35(40) |
35(40) |
35(40) |
35(40) |
||||||||||||||||||||||||||||||||||
|
σ^ |
15 |
|||||||||||||||||||||||||||||||||||||
|
Load softening temperature /℃(0.2MPa,T 0.6 ) |
μ0≥ |
1700 |
1700 |
1700 |
1700 |
1700 |
||||||||||||||||||||||||||||||||
|
σ^ |
20 |
|||||||||||||||||||||||||||||||||||||
|
Thermal shock resistance/times |
Data provided |
|||||||||||||||||||||||||||||||||||||
|
Note 1: Thermal ductility can be tested according to user requirements. Note 2: Data for unsalted bricks are in parentheses. The single value of compressive strength measured should be greater than the specified value of Xmin. |
||||||||||||||||||||||||||||||||||||||
|
Table 3 Physical and chemical indexes of electromelted semi-recombined magnesia-chrome brick |
||||||||||||
|
Items |
Indicators |
|||||||||||
|
BMGe-26 |
EMGe-24 |
BMGe-22 |
BMGe-20A |
BMGe-20B |
||||||||
|
w(MgO)/% |
μ0≥ |
50 |
50 |
55 |
58 |
55 |
||||||
|
σ^ |
2.5 |
|||||||||||
|
w(Cr2O3)/% |
μ0≥ |
26 |
24 |
22 |
20 |
20 |
||||||
|
σ^ |
1.5 |
|||||||||||
|
w(SiO2)/% |
μ0≤ |
2.0 |
2.0 |
2.0 |
2.0 |
2.5 |
||||||
|
σ^ |
0.3 |
|||||||||||
|
显气孔率/% |
μ0≤ |
16(15) |
16(15) |
16(15) |
16(15) |
16(15) |
||||||
|
σ^ |
1.5 |
|||||||||||
|
Apparent porosity /% |
μ0≥ |
40(45) |
40(45) |
40(45) |
40(45) |
35(40) |
||||||
|
xmin |
35(40) |
35(40) |
35(40) |
35(40) |
30(35) |
|||||||
|
σ^ |
15 |
|||||||||||
|
Compressive strengtha /MPa at room temperature |
μ0≥ |
1700 |
1700 |
1700 |
1700 |
1700 |
||||||
|
σ^ |
20 |
|||||||||||
|
Thermal shock resistance/times |
Data provided |
|||||||||||
|
Items |
Indicators |
|||||||||||
|
BMGe-18 |
BMGe-16A |
BMGe-16B |
BMGe-12A |
BMGe-12B |
||||||||
|
w(MgO)/% |
μ0≥ |
58 |
60 |
55 |
68 |
65 |
||||||
|
σ^ |
2.5 |
|||||||||||
|
w(Cr2O3)/% |
μ0≥ |
18 |
16 |
16 |
12 |
12 |
||||||
|
σ^ |
1.5 |
|||||||||||
|
w(SiO2)/% |
μ0≤ |
2.0 |
2.0 |
2.5 |
2.0 |
2.5 |
||||||
|
σ^ |
0.3 |
|||||||||||
|
Apparent porosity /% |
μ0≤ |
16(15) |
16(15) |
17(15) |
16(15) |
16(15) |
||||||
|
σ^ |
1.5 |
|||||||||||
|
Compressive strengtha /MPa at room temperature |
μ0≥ |
40(45) |
40(45) |
35(40) |
40(45) |
35(40) |
||||||
|
xmin |
35(40) |
35(40) |
30(35) |
35(40) |
30(35) |
|||||||
|
σ^ |
15 |
|||||||||||
|
Load softening temperature /℃(0.2MPa,T 0.6 ) |
μ0≥ |
1700 |
1700 |
1700 |
1700 |
1700 |
||||||
|
σ^ |
20 |
|||||||||||
|
Thermal shock resistance/times |
Data provided |
|||||||||||
|
Note 1: Thermal shock resistance can be tested according to user requirements. Note 2: Data for unsalted bricks are in parentheses. The single value of compressive strength measured should be greater than the specified value of Xmin. |
||||||||||||
|
Table 4 Physical and chemical indexes of common magnesia-chromium brick |
|||||||
|
Items |
Indicators |
||||||
|
MGe-16A |
MGe-16B |
MGe-12A |
MGe-12B |
MGe-8A |
MGe-8B |
||
|
w(MgO)/% |
μ0≥ |
50 |
45 |
60 |
55 |
65 |
60 |
|
σ^ |
2.5 |
||||||
|
w(Cr2O3)/% |
μ0≥ |
16 |
16 |
12 |
12 |
8 |
8 |
|
σ^ |
1.5 |
||||||
|
Apparent porosity /% |
μ0≤ |
19 |
22 |
19 |
21 |
19 |
21 |
|
σ^ |
1.5 |
||||||
|
Compressive strengtha /MPa at room temperature |
μ0≥ |
35 |
25 |
35 |
30 |
35 |
30 |
|
xmin |
30 |
20 |
30 |
25 |
30 |
25 |
|
|
σ^ |
15 |
||||||
|
Load softening temperature /℃(0.2MPa,T 0.6 ) |
μ0≥ |
1650 |
1550 |
1650 |
1550 |
1650 |
1530 |
|
σ^ |
20 |
||||||
|
The single value of compressive strength measured should be greater than the specified value of Xmin. |
|||||||
Table 5. Permissible size deviation and appearance of bricks
|
Items |
Indicators |
|||
|
Allowable deviation of dimension |
Surface of machining |
±0.5 |
||
|
Dimensions≤200 |
±1.5 |
|||
|
Dimensions 201-300 |
士3.0 |
|||
|
Dimensions>300 |
士4.0 |
|||
|
Distortion |
Surface of machining |
0.5 |
||
|
Length≤350 |
1.5 |
|||
|
Length>350 |
2.0 |
|||
|
Missing Angle length(a+b+c) |
Face of work |
40 |
||
|
Non working face |
60 |
|||
|
Missing edge length(e+f+g) |
Face of work |
50 |
||
|
Non working face |
70 |
|||
|
Crack length |
Breadth≤0.10 |
Unlimited |
||
|
Breadth 0.11~0.25 |
Face of work |
50 |
||
|
Non working face |
80 |
|||
|
Breadth 0.26~0.5 |
Face of work |
30 |
||
|
Non working face |
50 |
|||
|
Breadth>0.5 |
Be forbidden from |
|||
|
Thickness relative to edge difference |
1.0 |
|||
|
Note 1: The number of missing edges and corners: working face ≤2, non-working face ≤3, the total of each brick <3. Note 2: Only one edge is allowed when the crack crosses the edge, and the cross edge crack is combined. |
||||
6.Test methods
6.1 Bricks shall be inspected and prepared according to GB/T 7321.
6.2 Chemical analysis was performed according to GB/T 5070.
6.3 The apparent porosity test was carried out according to GB/T 2997.
6.4 The compressive strength at room temperature shall be tested according to GB/T 5072.
6.5 The test of the softening temperature under load is carried out according to YB/T 370.
6.6 The test of heat resistance shall be carried out according to YB/T 376.1 or YB/T 376.2.
6.7 The inspection of the size, appearance and section of the brick shall be carried out according to GB/T 10326
7 Quality assessment procedures.
7.1 Batch
Products according to the same grade batch, each batch is not more than 300t.
7.2 Rules for sampling and conformity determination
The sampling and acceptance of bricks shall be carried out according to GB/T 10325. Chemical composition, apparent porosity, resoftening temperature and normal temperature compressive strength are the acceptance test items.
7.3 Form of conformity assessment
The conformity assessment can be made in the form of the supplier’s declaration, the user’s certification or the third party’s certification.
8 Packing, marking, transportation, storage and quality certificate
8.1 The bricks shall be packed in pallets or according to user’s requirements.
8.2 Bricks are transported and stored in accordance with GB/T 16546.
8.3 The marking of the hot surface of the rotary compact firebrick shall comply with the provisions of GB/T 18257, and may also be marked according to the drawings or requirements provided by the buyer.
8.4 The bricks shall be issued with a quality certificate issued by the quality department of the supplier, which shall state the name of the supplier or the broad label, the name of the supplier, the date of delivery, the contract number, the standard number, the product name, the brand number, the brick number, the lot number and the corresponding physical and chemical inspection results.
