JC/T 638-2013 玻璃窑用低气孔率粘土砖/Low porosity clay bricks for glass kilns
玻璃窑用低气孔率粘土砖
1范围
本标准规定了玻璃窑用低气孔率粘土砖的术语和定义、分类及形状尺寸、技术要求、试验方法、检验规则以及标志、包装、运输、贮存和质量证明书等。本标准适用于玻璃窑用低气孔率粘土砖。
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。
GBT 5072耐火材料 常温耐压强度试验方法。
GB/T 5073耐火材料 压蠕变试验方法。
GB/T 5988耐火材料 加热永久线变化试验方法。
GB/T 6900铝硅系耐火材料化学分析方法。
GB/T 7321定形耐火制品试样制备方法。
GB/T 10326定形耐火制品尺寸、外观及断面的检查方法。
GB/T 16546定形耐火制品包装、标志、运输和储存。
GB/T 18930耐火材料术语。
GB/T 20511耐火制品分型规则。
GB/T 21114耐火材料 X射线荧光光谱化学分析 熔铸玻璃片法。
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耐火倒品抗热震性试验方法(水急冷法)。
3术语和定义
GB/T 18930界定的以及下列术语和定义适用于本文件。
3.1
低气孔率耐火砖 low porosity refractory bricks
以粘土熟料为主要原料,加入硅线石、红柱石等铝硅系材料,经压制、烧成的低气孔率粘土制品。
4分类及形状尺寸
4.1制品按显气孔率将具分为DN-11、DN-14和DN-17三个牌号。牌号中D、N分别是低、粘的汉语拼音首字母,数字分别为低气孔耐火砖的显气孔率。
4.2制品的形状尺寸应符合GB/T 2992.1和GB/T 20511的规定,也可按需方提供的图纸生产。
5技术要求
5.1制品的理化性能指标应符合表1的规定。
表1制品的理化性能指标 |
|||||||
项目 |
指标 |
||||||
DN-11 |
DN-14 |
DN-17 |
|||||
化学成分 |
w(Al2O3)/% |
μ0 |
≥47 |
≥45 |
≥42 |
||
σ |
1.0 |
1.0 |
1.0 |
||||
w(Fe2O3)/% |
μ0 |
≤1.2 |
≤1.5 |
≤1.8 |
|||
σ |
0.2 |
0.2 |
0.2 |
||||
物理性能 |
体积密度/(g/cm3) |
μ0 |
≥2.40 |
≥2.34 |
≥2.26 |
||
σ |
0.02 |
0.02 |
0.02 |
||||
显气孔率/% |
μ0 |
≤11 |
≤14 |
≤17 |
|||
σ |
1.0 |
1.0 |
1.0 |
||||
耐压强度/MPa |
μ0 |
≥80 |
≥65 |
≥50 |
|||
σ |
10 |
10 |
10 |
||||
Xmin |
70 |
55 |
40 |
||||
荷重软化温度T/℃ |
μ0 |
≥1520 |
≥1 470 |
≥1 430 |
|||
σ |
10 |
10 |
10 |
||||
加热永久线变化/% |
1 400℃x2h |
L~U |
– |
+0.1~-0.2 |
|||
σ |
|
0.02 |
|||||
1500℃x2h |
L~U |
+0.1~-0.2 |
– |
||||
σ |
0.02 |
||||||
蠕变率/% |
1200℃x50h,0.2MPa |
– |
由供需双方商定 |
– |
|||
抗热震性/次 |
1100℃,水冷 |
– |
由供需双方商定 |
5.2制品的尺寸允许偏差与外观质量应符合表2的规定
表2尺寸允许偏差与外观质量 单位为毫米 |
||
项目 |
范围 |
指标 |
尺寸允许偏差 |
≤100 |
土1.0 |
101~300 |
±2.0 |
|
>300 |
士1% |
|
扭曲 |
≤0.5% |
|
缺角 |
≤20允许,20<a+b+c<50允许两处,≥50不允许 |
|
缺棱 |
≤30允许,30<e+f+g<50允许两处,≥60不允许 |
|
熔洞直径 |
≤6 |
|
裂纹长度 |
宽度≤0.25 |
允许 |
宽度0.26~0.50 |
≤20,不超过两处 |
|
宽度>0.50 |
不允许 |
|
断面层裂 |
不允许 |
|
注1:特殊形状产品的外观质量和尺寸偏差由供需双方商定。 注2:简形砖按高度差由供需双方商定分档包装。 |
6试验方法
6.1样品制备
按GB/T 7321的规定进行。
6.2 Al2O3、Fe2O3;的检验
按GB/T 6900或GB/T 21114的规定进行,其中GB/T 6900是仲裁法。
6.3体积密度、显气孔率的检验
按GB/T 2997的规定进行。
6.4耐压强度的检验
可按GB/T 5072的规定进行。
6.5荷重软化温度的检验
按YB/T370的规定进行。
6.6加热永久线变化的检验
按GB/T 5988的规定进行。
6.7磐变率的检验
按GB/T 5073的规定进行。
6.8抗热震性的检验
按YB/T 376.1的规定进行。
6.9尺寸偏差和外观质最的检验
按GB/T10326的规定进行。
7检验分类
检验按类型分为出检验和型式检验。
7.1.1出厂检验
产品出厂时,应进行出厂检验。出厂检验的检验项目为:外观质量、尺寸偏差、Al2O3 含量、显气孔率和常温耐压强度。
7.1.2型式检验
型式检验项目包括第5章技术要求规定的全部项目。在下列情况下进行型式检验:
a)生产工艺或原材料有较大改变时;
b)正常生产时,每年至少进行两次;
c)停产半年以上,恢复生产时;
d)出检验结果与上次型式检验结果有较大差异时。
7.2组批
产品按同样生产条件下同牌号组批,每批不超过300t。
7.3抽样
7.3.1外观质量和尺寸偏差检验抽样
本标准给出的外观质量和尺寸偏差抽样检验方案是按可接收质量限AOL制定的,见表3。如没有特别规定,外观检验按AQL=4.0,尺寸检验按AOL=6.5抽样方案进行,如果对外观质量和尺寸偏差有重严格要求时,外观质量可选择AOL=L.5,尺寸偏差可选择AOL=4.0抽样方案,但需要在双方协议中注明。
外观质量和尺寸偏差检验的样本,通常应在制造厂交付的成品垛中一次性随机抽取。为了便于抽样制造厂交付的制品应按砖型和生产时间顺序整齐码放,并留抽样作业通道。抽样前,应先清点交付的砖型子批中单位产品的数量(N),再按表3规定的样本量(n)抽取样品。当外观和尺寸规定的抽样数一致时,抽样总数-外观抽样数尺寸抽样数,所抽样品的外观和尺寸分别检验,按各自对应的接收数AC进行质量判定,当外观和尺寸规定的抽样数》不同时,抽样总数应接,大的数一次抽取,所抽样品的外观和尺寸全部进行检验,然后按各自对应的接收数Ac进行质量判定。
表3外观和尺寸检验抽样方案 |
|||
接收质量限AQL% |
批量N块 |
样本量n坎 |
接收数Ac块 |
1.5 |
≤31 |
N |
剔除不合格品 |
32~1200 |
32 |
1 |
|
1201~3200 |
50 |
2 |
|
3201~10000 |
80 |
3 |
|
>10 000 |
125 |
5 |
|
4 |
≤12 |
N |
剔除不合格品 |
13~280 |
13 |
1 |
|
281~500 |
20 |
2 |
|
501~1200 |
32 |
3 |
|
1201~3200 |
50 |
5 |
|
3201~10000 |
80 |
7 |
|
>10000 |
125 |
10 |
|
6.5 |
≤7 |
N |
剔除不合格品 |
8~150 |
8 |
1 |
|
151~280 |
13 |
2 |
|
281~500 |
20 |
3 |
|
501~1200 |
32 |
5 |
|
1201~3200 |
50 |
7 |
|
3201~10000 |
80 |
10 |
|
>10000 |
125 |
14 |
7.3.2理化性能检验抽样
理化质量特性检验应在成品垛上随机抽取12块样品,其中6块样品按表 1进行单项检测,其余6块当单项检测出现不合格项目时进行不合格项目的加项检测,样品不得有影响理化质量特性的外观缺陷。
7.4判定规则
7.4.1外观质量和尺寸偏差判定
样品抽取后,应按产品质量标准的要求对每件样品的外观质量和尺寸偏差质量分别做出“合格”或“不合格”判定。所有样品检测后,分别统计外观和尺寸累计不合格样品的数量(y),并将y与表3中规定的接收数Ac进行比较。若S≤Ac,判该子批制品合格:若>AC,则判该子批制品不合格。外观或尺寸检验不合格子批,如果通过检选可以别除批中的不合格品,允许生产方检选后重新交付,再次进行验收。如果不合格子批不能通过枪选提高质量,则拒收该批产品。
7.4.2理化性能的判定
定形耐火制品理化质量特性的验收抽样检验项目包括Al2O3含量、Fe2O3,含量,体积密度、显气孔率、耐压强度、荷重软化温度和加热永人线变化,其中Al2O3;含量、Fe2O3;含量、荷重软化温度的判定可按表4和表5进行(两个表样本量不同,可以任选其一),体积密度、显气孔率、耐压强度的判定技表5进行,耐压强度的单值不允许低于 X其中是表1中的批偏差,S是出现检测不合格项时加测后9个样品的标准偏差,上述各项指标满足表4或者表5要求的判定为合格。
表4以批均值为质量指标的单一质量特性的合格/不合格判定(n=3) |
||||
质量要求 |
第一次测试1个样品 |
两次累计测试3个样品 |
||
测试结果 |
判定 |
测试结果 |
判定 |
|
低值不适 |
Xi ≥μ0 |
合格 |
– |
– |
Xi<μ0 |
继续检验 |
x的平均值≥μ0 |
合格 |
|
x的平均值<μ0 |
不合格 |
|||
高值不适 |
Xi≤μ0 |
合格 |
– |
– |
Xi>μ0 |
继续检验 |
x的平均值≤μ0 |
合格 |
|
x的平均值>μ0 |
不合格 |
表5以批均值为质量指标的单一质量特性的合格/不合格判定(n=9) |
||||
质量要求 |
第一次测试3个样 |
两次累计测试9个样 |
||
测试结果 |
判 定 |
测试结果 |
判定 |
|
低值不适 |
x的平均值≥μ0 |
合格 |
– |
– |
x的平均值<μ0-1.5σ |
不合格 |
– |
– |
|
μ0-1.5σ≤x的平均值<μ0 |
继续检验 |
x的平均值≥μ0-0.62S |
合格 |
|
x的平均值<μ0-0.62S |
不合格 |
|||
高值不适 |
x的平均值≤μ0 |
合格 |
– |
– |
x的平均值>μ0+1.5σ |
不合格 |
– |
– |
|
μ0<x的平均值≤μ0+1.5σ |
继续检验 |
x的平均值≥μ0+0.62S |
合格 |
|
x的平均值>μ0+0.62S |
不合格 |
加热永久线变化的判定按表6进行,其中。是表1中的批偏差,S是出现检测不合格项时加测后个样品的标准偏差,加热永久线变化满足表6要求的判定为合格。
表6以联合双侧规范限为质量指标的单一质量特性的合格/不合格判定(n=9) |
|||||
第一次测试3个样 |
两次累计测试9个样 |
||||
测试结果 |
判定 |
测试结果 |
判定 |
||
Xmax-Xmin> U-L |
不合格 |
– |
– |
||
Xmax-Xmin≤U-L |
L+1.5ơ≤x≤U-1.5σ |
合格 |
– |
– |
|
>L或<U |
不合格 |
– |
– |
||
L≤x<L+1.5ơ或U-1.5ơ≤<U |
继续检验 |
S≥(U-L)/2.2 |
不合格 |
||
S<(U-L)/2.2 |
L+1.1S≤≤U-1.1S |
合格 |
|||
<L+1.1S或>U-1.1S |
不合格 |
7.4.3综合判定
检验批所有应验收的理化质量特性和外观、尺寸质量应全部合格,则该批产品合格。
8标志、包装、运输、贮存和质量证明书
8.1标志、包装、运输和贮存
按GB/T 16546 进行。
8.2质量证明书
砖出厂时应附有质量证明书,质量证明书应包括:供方名称或厂标、需方名称、生产日期、合同号产品名称、标准编号、牌号、砖号、批号及相应的理化检验结果。
Low porosity clay bricks for glass kilns
1 Range
This standard specifies the terms and definitions, classification, shape and size, technical requirements, test methods, inspection rules, marking, packaging, transportation, storage and quality certificates of low porosity clay bricks for glass kilns. This standard is applicable to clay bricks with low porosity for glass kilns.
2 Normative reference documents
The following documents are essential for the application of this document. For dated references, the date-only 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.
Test method for compressive strength of GBT 5072 refractories at normal temperature.
GB/T 5073 refractories compressive creep test method.
GB/T 5988 refractory heating permanent line change test method.
GB/T 6900 aluminum-silicon refractory chemical analysis method.
GB/T 7321 shaped refractory product sample preparation method.
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 18930 refractory terminology.
GB/T 20511 classification rules for refractory products.
GB/T 21114 refractories by X-ray fluorescence spectrochemical analysis of fused cast glass sheets.
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 pour products (water quench cooling method).
3 Terms and definitions
GB/T 18930 and the following terms and definitions apply to this document.
3.1
Low porosity refractory bricks
Clay clinker as the main raw material, adding sillimanite, andalusite and other aluminum-silicon materials, pressed, fired clay products with low porosity.
4 Classification and shape size
4.1 Products are divided into three grades DN-11, DN-14 and DN-17 according to apparent porosity. In the grade, D and N are the initial letters of low and sticky Chinese pinyin respectively, and the numbers are the apparent porosity of low porosity refractory bricks respectively.
4.2 The shape and size of the product shall comply with the provisions of GB/T 2992.1 and GB/T 20511, and can also be produced according to the drawings provided by the demander.
5 Technical Requirements
5.1 The physical and chemical properties of the product shall comply with the provisions of Table 1.
Table 1 Physical and chemical properties of the product |
|||||||
Item |
Index |
||||||
DN-11 |
DN-14 |
DN-17 |
|||||
Chemical composition |
w(Al2O3)/% |
μ0 |
≥47 |
≥45 |
≥42 |
||
σ |
1.0 |
1.0 |
1.0 |
||||
w(Fe2O3)/% |
μ0 |
≤1.2 |
≤1.5 |
≤1.8 |
|||
σ |
0.2 |
0.2 |
0.2 |
||||
Physical property |
Bulk density/(g/cm3) |
μ0 |
≥2.40 |
≥2.34 |
≥2.26 |
||
σ |
0.02 |
0.02 |
0.02 |
||||
Apparent porosity/% |
μ0 |
≤11 |
≤14 |
≤17 |
|||
σ |
1.0 |
1.0 |
1.0 |
||||
Compressive strength/MPa |
μ0 |
≥80 |
≥65 |
≥50 |
|||
σ |
10 |
10 |
10 |
||||
Xmin |
70 |
55 |
40 |
||||
Softening temperature under loadT/℃ |
μ0 |
≥1520 |
≥1 470 |
≥1 430 |
|||
σ |
10 |
10 |
10 |
||||
Heating permanent line change/% |
1 400℃x2h |
L~U |
– |
+0.1~-0.2 |
|||
σ |
|
0.02 |
|||||
1500℃x2h |
L~U |
+0.1~-0.2 |
– |
||||
σ |
0.02 |
||||||
Creep rate/% |
1200℃x50h,0.2MPa |
– |
To be agreed upon by supply and demand |
– |
|||
Thermal shock resistance/time |
1100℃,water-cooling |
– |
To be agreed upon by supply and demand |
5.2 The permissible size deviation and appearance quality of the product shall comply with the provisions of Table 2
Table 2 Dimensions permissible deviation and apparent mass in millimeters |
||
Item |
Radius |
Index |
Allowable deviation of dimension |
≤100 |
土1.0 |
101~300 |
±2.0 |
|
>300 |
士1% |
|
Distortion |
≤0.5% |
|
Missing corner |
≤20 is allowed. 20<a+b+c<50 is allowed. ≥50 is not allowed |
|
Wane |
≤30 is allowed, 30<e+f+g<50 is allowed, and ≥60 is not allowed |
|
Hole diameter |
≤6 |
|
Crack length |
Dimension≤0.25 |
Allowed |
Dimension度0.26~0.50 |
≤20, not more than two places |
|
Dimension>0.50 |
Not allow |
|
Fracture lamination |
Not allow |
|
Note 1: The appearance quality and size deviation of special shape products shall be agreed by the supply and demand parties. Note 2: The simple brick is packaged according to the height difference agreed by the supply and demand parties. |
6 Test methods
6.1 Sample Preparation
According to GB/T 7321.
6.2 Al2O3, Fe2O3 inspection
In accordance with the provisions of GB/T 6900 or GB/T 21114, where GB/T 6900 is the arbitration law.
6.3 Test of bulk density and apparent porosity
According to GB/T 2997.
6.4 Test the compressive strength
Can be carried out in accordance with GB/T 5072.
6.5 Test of softening temperature under load
According to YB/T370.
6.6 Test the change of heating permanent line
According to GB/T 5988.
6.7 Testing of planetary variability
According to GB/T 5073.
6.8 Test thermal shock resistance
According to YB/T 376.1.
6.9 Check the size deviation and appearance quality
According to GB/T10326.
7 Test Classification
Inspection is divided into inspection and type inspection according to the type.
7.1.1 Factory inspection
The product shall be inspected before leaving the factory. The inspection items of factory inspection are: appearance quality, size deviation, Al2O3 content, apparent porosity and pressure strength at room temperature.
7.1.2 Type inspection
Type inspection items include all items specified in Chapter 5 Technical requirements. Type inspection is performed in the following cases:
- a) When there is a major change in the production process or raw materials;
- b) During normal production, at least twice a year;
- c) stop production for more than half a year and resume production;
- d) When there is a big difference between the test result and the last type test result.
7.2 Batch Group
Products according to the same production conditions of the same brand batch, each batch does not exceed 300t.
7.3 Sampling
7.3.1 Appearance quality and dimensional deviation inspection sampling
The sampling inspection scheme of appearance quality and dimension deviation given in this standard is formulated according to the acceptable quality limit AOL, see Table 3. If there is no special stipulation, the appearance inspection shall be conducted according to AQL=4.0, and the size inspection shall be conducted according to AOL=6.5 sampling scheme. If there are strict requirements for appearance quality and size deviation, AOL=L.5 can be selected for appearance quality, and AOL=4.0 sampling scheme can be selected for size deviation, which shall be indicated in the agreement between the two parties.
Samples for inspection of appearance quality and dimensional deviation should normally be randomly selected at one time in the finished product stacks delivered by the manufacturer. In order to facilitate sampling, the products delivered by the manufacturer shall be placed neatly in brick shape and production time order, and the sampling operation channel shall be left. Before sampling, the number of units of product (N) in the brick sublot delivered shall be counted and samples shall be taken according to the sample size (n) specified in Table 3. When the sampling numbers specified in appearance and size are consistent, the total number of samples – appearance sampling number and size sampling number, the appearance and size of the samples are inspected respectively, and the quality is determined according to the corresponding receiving number AC. When the sampling numbers specified in appearance and size are different, the total number of samples shall be connected, and the large number shall be sampled once, and the appearance and size of all samples shall be inspected. Then the quality is judged according to the corresponding receiving number Ac.
Table 3 Sampling scheme for appearance and dimension inspection |
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Receive quality limit AQL% |
Batch N block |
Sample size n n |
Number of received Ac blocks |
1.5 |
≤31 |
N |
Eliminate nonconforming products |
32~1200 |
32 |
1 |
|
1201~3200 |
50 |
2 |
|
3201~10000 |
80 |
3 |
|
>10 000 |
125 |
5 |
|
4 |
≤12 |
N |
Eliminate nonconforming products |
13~280 |
13 |
1 |
|
281~500 |
20 |
2 |
|
501~1200 |
32 |
3 |
|
1201~3200 |
50 |
5 |
|
3201~10000 |
80 |
7 |
|
>10000 |
125 |
10 |
|
6.5 |
≤7 |
N |
Eliminate nonconforming products |
8~150 |
8 |
1 |
|
151~280 |
13 |
2 |
|
281~500 |
20 |
3 |
|
501~1200 |
32 |
5 |
|
1201~3200 |
50 |
7 |
|
3201~10000 |
80 |
10 |
|
>10000 |
125 |
14 |
7.3.2 Sampling for physical and chemical properties inspection
For physical and chemical quality characteristic inspection, 12 samples should be randomly selected from the finished stack, of which 6 samples should be carried out a single test according to Table 1, and the remaining 6 samples should be tested with additional items when unqualified items are found in a single test. The samples should not have appearance defects affecting physical and chemical quality characteristics.
7.4 Decision Rules
7.4.1 Determination of appearance quality and size deviation
After sample extraction, the appearance quality and dimensional deviation quality of each sample should be determined as “qualified” or “unqualified” according to the requirements of product quality standards. After all samples were tested, the number of accumulated nonconforming samples (y) of appearance and size were counted respectively, and y was compared with the number of acceptances Ac specified in Table 3. If S≤Ac, the sub-batch product is qualified: if >AC, the sub-batch product is disqualified. The appearance or size inspection of the unqualified batch, if passed the inspection can be removed from the batch of unqualified products, allowing the production party to re-deliver after the inspection, again for acceptance. If the quality of the unqualified batch cannot be improved by gun selection, the batch is rejected.
7.4.2 Determination of physical and chemical properties
The acceptance sampling inspection items of physical and chemical quality characteristics of shaped refractory products include Al2O3 content, Fe2O3, content, bulk density, apparent porosity, compressive strength, load softening temperature and heating permanent line change, in which Al2O3; Content, Fe2O3; The determination of content and load softening temperature can be carried out according to Table 4 and Table 5 (the sample size of the two tables is different, you can choose one of them), and the determination technique of bulk density, apparent porosity and compressive strength can be carried out in Table 5. The single value of compressive strength is not allowed to be lower than X, where is the batch deviation in Table 1, and S is the standard deviation of 9 samples after the detection of nonconforming items. The above indicators meet the requirements of Table 4 or Table 5.
Table 4 Pass/Fail determination of a single quality feature with batch average as quality index (n=3) |
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Quality requirement |
Test 1 sample for the first time |
Three samples were tested twice |
||
Test result |
Determine |
Test result |
Determine |
|
Low-value discomfort |
Xi ≥μ0 |
Qualified |
– |
– |
Xi<μ0 |
Further inspection |
≥μ0 |
Qualified |
|
<μ0 |
Below standard |
|||
High value discomfort |
Xi≤μ0 |
Qualified |
– |
– |
Xi>μ0 |
Further inspection |
≤μ0 |
Qualified |
|
>μ0 |
Below standard |
Table 5 Pass/Fail determination of a single quality feature with lot average as quality index (n=9) |
||||
Quality requirement |
Test 3 samples for the first time |
A total of 9 samples were tested twice |
||
Test result |
Determine |
Test result |
Determine |
|
Low-value discomfort |
Mean of x≥μ0 |
Qualified |
– |
– |
Mean of x<μ0-1.5σ |
Below standard |
– |
– |
|
μ0-1.5σ≤Mean of x<μ0 |
Further inspection |
Mean of x≥μ0-0.62S |
Qualified |
|
Mean of x<μ0-0.62S |
Below standard |
|||
High value discomfort |
Mean of x≤μ0 |
Qualified |
– |
– |
Mean of x>μ0+1.5σ |
Below standard |
– |
– |
|
μ0<Mean of x≤μ0+1.5σ |
Further inspection |
Mean of x≥μ0+0.62S |
Qualified |
|
Mean of x>μ0+0.62S |
Below standard |
The determination of the change of the heating permanent line is carried out according to Table 6, where. Is the batch deviation in Table 1, S is the standard deviation of the next sample after testing when the unqualified item occurs, and the change of the heating permanent line meets the requirements in Table 6.
Table 6 Pass/Fail determination of single quality feature with joint bilateral specification limit as quality index (n=9) |
|||||
Test 3 samples for the first time |
A total of 9 samples were tested twice |
||||
Test result |
Determine |
Test result |
Determine |
||
Xmax-Xmin> U-L |
Below standard |
– |
– |
||
Xmax-Xmin≤U-L |
L+1.5ơ≤x≤U-1.5σ |
Qualified |
– |
– |
|
>L或<U |
Below standard |
– |
– |
||
L≤x<L+1.5ơ或U-1.5ơ≤<U |
Further inspection |
S≥(U-L)/2.2 |
Below standard |
||
S<(U-L)/2.2 |
L+1.1S≤≤U-1.1S |
Qualified |
|||
<L+1.1S或>U-1.1S |
Below standard |
7.4.3 Comprehensive judgment
If all the physical and chemical quality characteristics, appearance and dimension quality of the inspection batch to be accepted are qualified, the batch of products is qualified.
8 Marking, packing, transportation, storage and quality certificate
8.1 Marking, packaging, transportation and storage
Proceed as GB/T 16546.
8.2 Certificate of Quality
The quality certificate shall include the supplier’s name or factory standard, demander’s name, production date, contract number, product name, standard number, brand number, brick number, batch number and corresponding physical and chemical inspection results.