Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This document is developed in accordance with the rules given in GB/T 1.1-2020 Directives for Standardization — Part 1: Rules for the Structure and Drafting of Standardizing Documents.
This standard replaces GB 11614-2009 Flat Glass. In addition to structural adjustment and editorial changes, the following technical deviations have been made with respect to GB 11614-2009:
— the definition of bloom is added (see 3.5).
— the classification is modified into classification and grading (see Clause 4 hereof; Clause 4 of Edition 2009);
— the three grades of acceptable products, first-class products and superior products divided by appearance quality are modified into two grades of sheet flat glass and high quality processing flat glass (see 4.2 hereof; 4.2 of Edition 2009);
— the thickness deviation and thickness difference are modified (see Table 3 hereof; Table 3 of Edition 2009);
— the minimum and permissible number of spot defects are modified (see 5.5 hereof; 5.5 of Edition 2009);
— The requirements for optical distortion are modified (see 5.5 hereof; 5.5 of Edition 2009);
— the requirements for transmission deviation and color uniformity of bulk tined flat glass are modified (see 5.8.2 and 5.9 hereof; 5.7.2 and 5.7.3 of Edition 2009);
— the requirements, inspection methods and determination rules for bloom are added (see 5.7, 6.7, 7.3.3).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing body of this document shall not be held responsible for identifying any or all such patent rights.
This standard was proposed by and is under the jurisdiction of the Ministry of Industry and Information Technology of the People's Republic of China.
The previous editions of this document are as follows:
— GB 4871-1985, GB 4871-1995;
— GB 11614-1989, GB 11614-1999, GB 11614-2009;
— GB/T 18701-2002.
Flat Glass
1 Scope
This document specifies the classification and grading, requirements, test methods, inspection rules, marking, packaging, transportation and storage of flat glass.
This document is applicable to soda-calcium-silicon flat glass, with thickness not less than 2mm, produced by various processes.
This document is not applicable to embossed glass and filamentable glass.
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 1216 External Micrometer
GB/T 2680 Glass in Building — Determination of Light Transmittance, Solar Direct Transmittance, Total Solar Energy Transmittance, Ultraviolet Transmittance and Related Glazing Factors
GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values
GB/T 9056 Metal Ruler
GB/T 11942 Colorimetric Methods for Colour Building Materials
GB/T 15764 Standard Terminology of Flat Glass
GB/T 22523 Feeler Gauge
JB/T 2369 Reading Microscope
QB/T 2443-2011 Steel Measuring Tapes
3 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 15764 and the following apply.
3.1
optical distortion
defects that distort when viewed through glass at a certain angle.
Note: The degree of distortion is expressed by incident angle (also known as Zebra Angle).
3.2
spot faults
general term for defects such as bubbles, inclusions, spots, etc.
3.3
edge defects
glass plate section convex or concave or incomplete phenomenon
Note: Edge defects include edge bursting, edge concave and convex, broken corner, hypotenuse, etc.
3.4
thickness wedge
difference between the maximum and minimum thickness of the same piece of glass
3.5
bloom
after heating and cooling for a specified time, float glass of different thickness shows light interference color when visually observed on the lower surface of the glass (the surface in contact with the tin liquid when forming)
3.6
spot distortion
spot on the surface of flat glass that causes optical distortion
4 Classification and Grading
4.1 According to the color properties, flat glass can be divided into colorless transparent flat glass and body tined flat glass.
4.2 According to the different appearance quality requirements, flat glass can be divided into sheet flat glass and high quality processing flat glass.
5 Requirements
5.1 General
The inspection items, requirements and inspection methods of flat glass are shown in Table 1.
Table 1 Corresponding clause of inspection items, requirements and inspection methods
Inspection item Corresponding requirements Inspection method
Dimensional deviation 5.2 6.1
Diagonal difference 5.3 6.2
Thickness 5.4 6.3
Thickness wedge 5.4 6.4
Appearance quality Spot faults 5.5 6.5.1
Density of spot faults 5.5 6.5.2
Threads, scratches, cracks 5.5 6.5.3
Optical distortion 5.5 6.5.4
Edge defects 5.5 6.5.5
Curvature 5.6 6.6
Bloom 5.7 6.7
Optical property Visible light transmittance of colorless transparent flat glass 5.8.1 6.8.1
Transmission ratio deviation of body tined flat glass 5.8.2 6.8.2
Color uniformity 5.9 6.9
5.2 Dimensional deviation
Flat glass shall be cut into rectangles, the dimensional deviations of its length and width shall not exceed those specified in Table 2.
Table 2 Dimensional deviation
Dimensions in millimeters
Thickness, D Dimensional deviation
Side length (L) ≤ 3000 Side length (L) > 3000
2 ≤ D ≤ 6 ± 2 ± 3
6 < D ≤ 12 +2, -3 +3, -4
12 < D ≤ 19 ± 3 ± 4
D > 19 ± 5 ± 5
5.3 Diagonal difference
The diagonal difference shall be no more than 0.2% of the average diagonal length.
5.4 Thickness and thickness wedge
5.4.1 Common thickness specifications of flat glass are 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 8 mm, 10 mm, 12 mm, 15 mm, 19 mm, 22 mm and 25 mm, and the thickness shall be indicated in the product qualification certificate. Products outside the common thickness specifications should not be manufactured. When flat glass is used in other fields other than construction glass, such as information technology industry, photovoltaic, vehicles, household appliances and other fields, and has special requirements for thickness, products other than the common thickness specifications can be manufactured, and the thickness of the product shall be agreed and expressed in the contract and other documents.
5.4.2 Thickness deviation and thickness wedge of flat glass shall meet the requirements of Table 3.
Table 3 Thickness deviation and thickness wedge
Dimensions in millimeters
Thickness, D Thickness deviation Thickness wedge
5.5 Appearance quality
5.5.1 The appearance quality of sheet flat glass shall meet the requirements of Table 4.
Table 4 Appearance quality of sheet flat glass
Kind of defect Requirements
Spot faults a Dimensions (L) Allowable number limit
0.3 mm ≤ L ≤ 0.5 mm 2 × S
0.5 mm ≤ L ≤ 1.0 mm 1 × S
1.0 mm ≤ L ≤ 1.5 mm 0.2 × S
L > 1.5 mm 0
Density of spot faults The minimum spacing of spot faults of dimension (L) ≥ 0.3 mm shall not be less than 300 mm;
Within a circle with a diameter of 100 mm, there shall be no more than 3 spot faults of dimension (L) ≥ 0.2 mm
Thread Not permitted
Craze Not permitted
Scratch Allowable range Allowable number limit
Width (W) ≤ 0.2 mm, length (L) ≤ 40 mm 2 × S
Optical distortion Thickness, D Colorless transparent flat glass Body tined flat glass
2 mm ≤ D ≤ 3 mm ≥45° ≥45°
3 mm < D ≤ 4 mm ≥50° ≥45°
4 mm ≤ D ≤ 12mm ≥55° ≥50°
D > 12mm ≥50° ≥45°
Edge defects Not more than the thickness of the glass plate for the thickness not more than 8 mm; not exceed 8 mm for the thickness is above 8 mm
S is the value of the glass plate area in square meters, which shall be rounded off according to GB/T 8170, keeping two decimal places. The allowable number limit of spot faults and the allowable limit of the number of scratches are the values obtained by multiplying each coefficient with S, which shall be rounded off to an integer according to GB/T 8170.
a The light distortion point is regarded as the spot fault of 0.3 mm ≤ L ≤ 0.5 mm.
5.5.2 The appearance quality of high quality processing flat glass shall meet the requirements of Table 5.
Table 5 Appearance quality of high quality processing flat glass
Kind of defect Requirements
Spot faults a Dimensions (L) Allowable number limit
0.3mm ≤ L ≤ 0.5mm 1×S
0.5mm ≤ L ≤ 1.0mm 0.2×S
L> 1.0mm 0
Density of spot faults The minimum spacing of spot faults of dimension (L) ≥ 0.3 mm shall not be less than 300 mm;
Within a circle with a diameter of 100 mm, there shall be no more than 3 spot faults of dimension (L) ≥ 0.1mm
Thread Not permitted
Craze Not permitted
Scratch Allowable range Allowable number limit
Width (W) ≤ 0.1 mm, length (L) ≤ 30mm 2 × S
Optical distortion Thickness, D Colorless transparent flat glass Body tined flat glass
2 mm ≤ D ≤ 3 mm ≥50° ≥50°
3mm 12 mm ≥55° ≥50°
Edge defects Not more than the thickness of the glass plate for the thickness not more than 5mm; not exceed 5 mm for the thickness above 5mm
S is the value of the glass plate area in square meters, which shall be rounded off according to GB/T 8170, keeping two decimal places. The allowable number limit of spot faults and the allowable limit of the number of scratches are the values obtained by multiplying each coefficient with S, which shall be rounded off to an integer according to GB/T 8170.
a Light distortion points are not allowed in spot faults.
5.6 Curvature
Sheet flat glass shall not be more than 0.2%, high quality processing flat glass shall not be more than 0.1%.
5.7 Bloom
This test is only carried out on high quality processing flat glass produced by float process. After the test, there should be no bloom phenomenon.
5.8 Optical properties
5.8.1 Visible light transmittance of colorless transparent flat glass shall not be less than those specified in Table 6.For products with thickness other than the common specifications specified in 5.4.1, the measured value of visible light transmittance shall be converted into the visible light transmittance of 5 mm standard thickness, which shall be no less than those specified in Table 6.
Table 6 Visible light transmittance of colorless transparent flat glass
Thickness (mm) Visible light transmittance (%)
5.8.2 The deviation of visible light transmittance, direct solar transmittance and total solar transmittance of body tined flat glass shall not be greater than those specified in Table 7.
Table 7 Allowable values of transmittance deviation of body tined flat glass
Test item Permissible deviation value (%)
Visible light transmittance (wavelength range 380nm to 780nm) 1.5
Direct solar transmittance (wavelength range: 300nm to 2500nm) 2.5
Total solar transmittance (wavelength range: 300nm t0 2500nm) 3.0
5.9 Color uniformity
This test is only carried out on the body tined flat glass. In the same batch of products, the color difference of sheet flat glass is , and the color difference of high quality processing flat glass is .
6 Inspection Methods
6.1 Dimensional deviation
In the middle of the long and wide edges, the distance between two parallel edges is measured with a metal ruler of a dividing value of 1mm in accordance with GB/T 9056 or a steel tape with grade 1 precision in accordance with QB/T 2443-2011.The difference between the measured value and the nominal dimension is the dimensional deviation.
6.2 Diagonal difference
Two diagonal lengths of glass plates are measured with a grade 1 precision steel tape measure in accordance with QB/T 2443-2011. The absolute value of the difference is the diagonal difference, and the percentage of the diagonal difference and the average diagonal length can be calculated.
6.3 Thickness
Measure 5 points perpendicular to the pulling direction of the glass plate with a digital micrometer (or helical micrometer) with a dividing value of 0.001 mm in accordance with GB/T 1216: take a point inward from the edge about 15 mm, divide the remaining 3 points evenly between the two points. The measured value shall be rounded off to three decimal places. The difference between the measured values of 5 points and the expressed thickness can be calculated, and the maximum deviation shall be compared with Table 3.
Foreword II
1 Scope
2 Normative References
3 Terms and Definitions
4 Classification and Grading
5 Requirements
6 Inspection Methods
7 Inspection Rules
8 Marking, Packaging, Transportation and Storage
Annex A (Normative) Test Apparatus and Operating Parameters of Bloom
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This document is developed in accordance with the rules given in GB/T 1.1-2020 Directives for Standardization — Part 1: Rules for the Structure and Drafting of Standardizing Documents.
This standard replaces GB 11614-2009 Flat Glass. In addition to structural adjustment and editorial changes, the following technical deviations have been made with respect to GB 11614-2009:
— the definition of bloom is added (see 3.5).
— the classification is modified into classification and grading (see Clause 4 hereof; Clause 4 of Edition 2009);
— the three grades of acceptable products, first-class products and superior products divided by appearance quality are modified into two grades of sheet flat glass and high quality processing flat glass (see 4.2 hereof; 4.2 of Edition 2009);
— the thickness deviation and thickness difference are modified (see Table 3 hereof; Table 3 of Edition 2009);
— the minimum and permissible number of spot defects are modified (see 5.5 hereof; 5.5 of Edition 2009);
— The requirements for optical distortion are modified (see 5.5 hereof; 5.5 of Edition 2009);
— the requirements for transmission deviation and color uniformity of bulk tined flat glass are modified (see 5.8.2 and 5.9 hereof; 5.7.2 and 5.7.3 of Edition 2009);
— the requirements, inspection methods and determination rules for bloom are added (see 5.7, 6.7, 7.3.3).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing body of this document shall not be held responsible for identifying any or all such patent rights.
This standard was proposed by and is under the jurisdiction of the Ministry of Industry and Information Technology of the People's Republic of China.
The previous editions of this document are as follows:
— GB 4871-1985, GB 4871-1995;
— GB 11614-1989, GB 11614-1999, GB 11614-2009;
— GB/T 18701-2002.
Flat Glass
1 Scope
This document specifies the classification and grading, requirements, test methods, inspection rules, marking, packaging, transportation and storage of flat glass.
This document is applicable to soda-calcium-silicon flat glass, with thickness not less than 2mm, produced by various processes.
This document is not applicable to embossed glass and filamentable glass.
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 1216 External Micrometer
GB/T 2680 Glass in Building — Determination of Light Transmittance, Solar Direct Transmittance, Total Solar Energy Transmittance, Ultraviolet Transmittance and Related Glazing Factors
GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values
GB/T 9056 Metal Ruler
GB/T 11942 Colorimetric Methods for Colour Building Materials
GB/T 15764 Standard Terminology of Flat Glass
GB/T 22523 Feeler Gauge
JB/T 2369 Reading Microscope
QB/T 2443-2011 Steel Measuring Tapes
3 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 15764 and the following apply.
3.1
optical distortion
defects that distort when viewed through glass at a certain angle.
Note: The degree of distortion is expressed by incident angle (also known as Zebra Angle).
3.2
spot faults
general term for defects such as bubbles, inclusions, spots, etc.
3.3
edge defects
glass plate section convex or concave or incomplete phenomenon
Note: Edge defects include edge bursting, edge concave and convex, broken corner, hypotenuse, etc.
3.4
thickness wedge
difference between the maximum and minimum thickness of the same piece of glass
3.5
bloom
after heating and cooling for a specified time, float glass of different thickness shows light interference color when visually observed on the lower surface of the glass (the surface in contact with the tin liquid when forming)
3.6
spot distortion
spot on the surface of flat glass that causes optical distortion
4 Classification and Grading
4.1 According to the color properties, flat glass can be divided into colorless transparent flat glass and body tined flat glass.
4.2 According to the different appearance quality requirements, flat glass can be divided into sheet flat glass and high quality processing flat glass.
5 Requirements
5.1 General
The inspection items, requirements and inspection methods of flat glass are shown in Table 1.
Table 1 Corresponding clause of inspection items, requirements and inspection methods
Inspection item Corresponding requirements Inspection method
Dimensional deviation 5.2 6.1
Diagonal difference 5.3 6.2
Thickness 5.4 6.3
Thickness wedge 5.4 6.4
Appearance quality Spot faults 5.5 6.5.1
Density of spot faults 5.5 6.5.2
Threads, scratches, cracks 5.5 6.5.3
Optical distortion 5.5 6.5.4
Edge defects 5.5 6.5.5
Curvature 5.6 6.6
Bloom 5.7 6.7
Optical property Visible light transmittance of colorless transparent flat glass 5.8.1 6.8.1
Transmission ratio deviation of body tined flat glass 5.8.2 6.8.2
Color uniformity 5.9 6.9
5.2 Dimensional deviation
Flat glass shall be cut into rectangles, the dimensional deviations of its length and width shall not exceed those specified in Table 2.
Table 2 Dimensional deviation
Dimensions in millimeters
Thickness, D Dimensional deviation
Side length (L) ≤ 3000 Side length (L) > 3000
2 ≤ D ≤ 6 ± 2 ± 3
6 < D ≤ 12 +2, -3 +3, -4
12 < D ≤ 19 ± 3 ± 4
D > 19 ± 5 ± 5
5.3 Diagonal difference
The diagonal difference shall be no more than 0.2% of the average diagonal length.
5.4 Thickness and thickness wedge
5.4.1 Common thickness specifications of flat glass are 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 8 mm, 10 mm, 12 mm, 15 mm, 19 mm, 22 mm and 25 mm, and the thickness shall be indicated in the product qualification certificate. Products outside the common thickness specifications should not be manufactured. When flat glass is used in other fields other than construction glass, such as information technology industry, photovoltaic, vehicles, household appliances and other fields, and has special requirements for thickness, products other than the common thickness specifications can be manufactured, and the thickness of the product shall be agreed and expressed in the contract and other documents.
5.4.2 Thickness deviation and thickness wedge of flat glass shall meet the requirements of Table 3.
Table 3 Thickness deviation and thickness wedge
Dimensions in millimeters
Thickness, D Thickness deviation Thickness wedge
5.5 Appearance quality
5.5.1 The appearance quality of sheet flat glass shall meet the requirements of Table 4.
Table 4 Appearance quality of sheet flat glass
Kind of defect Requirements
Spot faults a Dimensions (L) Allowable number limit
0.3 mm ≤ L ≤ 0.5 mm 2 × S
0.5 mm ≤ L ≤ 1.0 mm 1 × S
1.0 mm ≤ L ≤ 1.5 mm 0.2 × S
L > 1.5 mm 0
Density of spot faults The minimum spacing of spot faults of dimension (L) ≥ 0.3 mm shall not be less than 300 mm;
Within a circle with a diameter of 100 mm, there shall be no more than 3 spot faults of dimension (L) ≥ 0.2 mm
Thread Not permitted
Craze Not permitted
Scratch Allowable range Allowable number limit
Width (W) ≤ 0.2 mm, length (L) ≤ 40 mm 2 × S
Optical distortion Thickness, D Colorless transparent flat glass Body tined flat glass
2 mm ≤ D ≤ 3 mm ≥45° ≥45°
3 mm < D ≤ 4 mm ≥50° ≥45°
4 mm ≤ D ≤ 12mm ≥55° ≥50°
D > 12mm ≥50° ≥45°
Edge defects Not more than the thickness of the glass plate for the thickness not more than 8 mm; not exceed 8 mm for the thickness is above 8 mm
S is the value of the glass plate area in square meters, which shall be rounded off according to GB/T 8170, keeping two decimal places. The allowable number limit of spot faults and the allowable limit of the number of scratches are the values obtained by multiplying each coefficient with S, which shall be rounded off to an integer according to GB/T 8170.
a The light distortion point is regarded as the spot fault of 0.3 mm ≤ L ≤ 0.5 mm.
5.5.2 The appearance quality of high quality processing flat glass shall meet the requirements of Table 5.
Table 5 Appearance quality of high quality processing flat glass
Kind of defect Requirements
Spot faults a Dimensions (L) Allowable number limit
0.3mm ≤ L ≤ 0.5mm 1×S
0.5mm ≤ L ≤ 1.0mm 0.2×S
L> 1.0mm 0
Density of spot faults The minimum spacing of spot faults of dimension (L) ≥ 0.3 mm shall not be less than 300 mm;
Within a circle with a diameter of 100 mm, there shall be no more than 3 spot faults of dimension (L) ≥ 0.1mm
Thread Not permitted
Craze Not permitted
Scratch Allowable range Allowable number limit
Width (W) ≤ 0.1 mm, length (L) ≤ 30mm 2 × S
Optical distortion Thickness, D Colorless transparent flat glass Body tined flat glass
2 mm ≤ D ≤ 3 mm ≥50° ≥50°
3mm 12 mm ≥55° ≥50°
Edge defects Not more than the thickness of the glass plate for the thickness not more than 5mm; not exceed 5 mm for the thickness above 5mm
S is the value of the glass plate area in square meters, which shall be rounded off according to GB/T 8170, keeping two decimal places. The allowable number limit of spot faults and the allowable limit of the number of scratches are the values obtained by multiplying each coefficient with S, which shall be rounded off to an integer according to GB/T 8170.
a Light distortion points are not allowed in spot faults.
5.6 Curvature
Sheet flat glass shall not be more than 0.2%, high quality processing flat glass shall not be more than 0.1%.
5.7 Bloom
This test is only carried out on high quality processing flat glass produced by float process. After the test, there should be no bloom phenomenon.
5.8 Optical properties
5.8.1 Visible light transmittance of colorless transparent flat glass shall not be less than those specified in Table 6.For products with thickness other than the common specifications specified in 5.4.1, the measured value of visible light transmittance shall be converted into the visible light transmittance of 5 mm standard thickness, which shall be no less than those specified in Table 6.
Table 6 Visible light transmittance of colorless transparent flat glass
Thickness (mm) Visible light transmittance (%)
5.8.2 The deviation of visible light transmittance, direct solar transmittance and total solar transmittance of body tined flat glass shall not be greater than those specified in Table 7.
Table 7 Allowable values of transmittance deviation of body tined flat glass
Test item Permissible deviation value (%)
Visible light transmittance (wavelength range 380nm to 780nm) 1.5
Direct solar transmittance (wavelength range: 300nm to 2500nm) 2.5
Total solar transmittance (wavelength range: 300nm t0 2500nm) 3.0
5.9 Color uniformity
This test is only carried out on the body tined flat glass. In the same batch of products, the color difference of sheet flat glass is , and the color difference of high quality processing flat glass is .
6 Inspection Methods
6.1 Dimensional deviation
In the middle of the long and wide edges, the distance between two parallel edges is measured with a metal ruler of a dividing value of 1mm in accordance with GB/T 9056 or a steel tape with grade 1 precision in accordance with QB/T 2443-2011.The difference between the measured value and the nominal dimension is the dimensional deviation.
6.2 Diagonal difference
Two diagonal lengths of glass plates are measured with a grade 1 precision steel tape measure in accordance with QB/T 2443-2011. The absolute value of the difference is the diagonal difference, and the percentage of the diagonal difference and the average diagonal length can be calculated.
6.3 Thickness
Measure 5 points perpendicular to the pulling direction of the glass plate with a digital micrometer (or helical micrometer) with a dividing value of 0.001 mm in accordance with GB/T 1216: take a point inward from the edge about 15 mm, divide the remaining 3 points evenly between the two points. The measured value shall be rounded off to three decimal places. The difference between the measured values of 5 points and the expressed thickness can be calculated, and the maximum deviation shall be compared with Table 3.
Contents of GB 11614-2022
Foreword II
1 Scope
2 Normative References
3 Terms and Definitions
4 Classification and Grading
5 Requirements
6 Inspection Methods
7 Inspection Rules
8 Marking, Packaging, Transportation and Storage
Annex A (Normative) Test Apparatus and Operating Parameters of Bloom
