This standard specifies the classification, size, technical requirements, inspection methods, inspection rules, packaging and marking, storage and transportation of ordinary flat glass. This standard applies to ordinary flat glass produced by the drawing method and used in construction and other aspects. GB 4871-1995 Ordinary Flat Glass GB4871-1995 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Ordinary flat glass
Sheet glass
1 Subject content and scope of application
GB 4871-1995
Replaces GB4871-85
This standard specifies the classification, size, technical requirements, inspection methods, inspection rules, packaging and marking, storage and transportation of ordinary flat glass.
This standard applies to ordinary flat glass produced by the drawing method and used in construction and other aspects. Reference standards
GB 1216
Outside micrometer
GB2680 Determination method of total visible light transmittance of flat glass GB/T6382.1 Flat glass container rack container and its test method GB/T6382.2 Flat glass container
JC/T513 Flat glass wooden box packaging
JB2546 Steel ruler
3 Classification
3.1 According to thickness: 2.3, 4.5mm four categories. Box container and its test method
3.2 According to grade: superior products, first-class products, qualified products three categories. 4 Size
Glass plate should be rectangular, the size is generally not less than 600mm×400mm. 5 Technical requirements
5.1 Thickness deviation should comply with the provisions of Table 1.
Allowable deviation
5.2 Dimension deviation, within 1500mm (including 1500mm) in length shall not exceed ±3mm, and over 1500mm in length shall not exceed ±4 mm.
Approved by the State Administration of Technical Supervision on November 30, 1995 and implemented on August 1, 1996
GB48711995
Dimension deviation, 1000mm in length, shall not exceed ±2mm. The curvature shall not exceed 0.3%.
The protruding or incomplete part of the edge shall not exceed 3mm, and a piece of glass shall only have one missing corner, which shall not exceed 5.5
5 mm measured along the original angle bisector.
5.6 The total transmittance of visible light shall not be lower than that specified in Table 2. Table 2
Thickness, mm
There shall be no indelible white foggy or brownish-yellow attachments on the glass surface. Appearance quality shall meet the classification requirements in Table 3. 5.7
Defect types
Maximum incident angle without deformation
(including corrugated roller flowers)
Length below 1mm
Superior products
Concentrated products are not allowed
Length greater than 1mm is allowed per square meter
Width ≤ 0.1mm
Number of lines allowed per square meter
Width ≥ 0.1mm, number of lines allowed per square meter
Non-destructive, diameter 0.5~2mm,
Number of lines allowed per square meter| |tt||The diameter of non-destructive nodules is not more than 3mm, the allowed number per square meter
[The allowed number of each piece of glass visible from the front
Concentrated pitting on the surface
Sparse pitting, the allowed number per square meter ≤6mm.6
Length ≤50mm
Not allowed
Not allowed
Not allowed
Not allowed
Note: ① Concentrated bubbles, pitting refers to more than 6 within a 100mm diameter circle area. 364
Total transmittance of visible light, %
First-class products
50mm edge, 30°
Concentration is not allowed
8mm, 8
>8~10 mm, 2
Length≤100mm
Width≤0.4mm
Length<100mm
30mm edge
Width≤0.5mm
Not allowed
Qualified productsWww.bzxZ.net
100mm edge, 0°
≤10mm, 12
>10~20 mm, 2
>20~25 mm,1
Width≤0.8mm
Length<100mm
Width≤0.5mm
No more than 3 places per square meter
GB 4871--1995
②The continuation of the sand grains, which can be seen at an angle of 0°. 5.8 The 15mm edge of the glass, first-class products and qualified products are allowed to have any non-destructive defects. 5.9 Glass is not allowed to have cracks.
5.10 Technical requirements not specified in the standard shall be negotiated by the supply and demand parties. 6 Inspection method
6.1 The size is measured with a metal ruler that meets the requirements of JB2546. 6.2 The thickness is measured at one point on each side of the glass plate with a micrometer that meets the requirements of GB1216. The thickness difference shall not exceed the requirements of Table 1. 6.3 The total transmittance of visible light shall be measured in accordance with GB2680 or using an equivalent instrument. 6.4 Determination of corrugation
6.4.1 Equipment
Light source: 24V150~240W halogen tungsten lamp.
Screen: white, non-reflective.
c. Bracket: can place the sample vertically and move parallel to the screen. 6.4.2 Inspection steps
The glass is placed vertically in the pulling direction, at an angle of 60° to the light, and 6m away from the light source. The white screen is parallel to the glass, 0.7m away, and the light and dark stripes on the screen are observed. The grade is determined by referring to the corrugation sample. 6.5 Inspection of bubbles, scratches, sand grains, lumps, pits, and lines6.5.1 Equipment
Black frame: equipped with several 40W fluorescent tubes, with a distance of 300mm between the tubes. 6.5.2 Inspection steps
Place the glass vertically in the pulling direction, parallel to the fluorescent tube and 600mm away. The observer is 600mm away from the glass and observes the glass vertically. The defect size is measured with a metal ruler that meets the requirements of JB2546 or a reading microscope with a magnification of 10 to 20 times. 6.6 Determination of curvature
Place the glass vertically, without applying external force, and place a ruler of sufficient length horizontally along the edge of the plate. When the glass is curved in an arch shape, measure the arc height corresponding to the chord length; when it is wavy, measure the depth of the trough (or the height of the crest) between the corresponding crests (or troughs) and the distance between them. Calculate the curvature according to the following formula:
Where: c—
curvature, %;
chord height or trough depth (or crest height), mm, h
-chord length or the distance between crests (or troughs), mm. L
6.7 Determination of dimensional deviation and missing corners
Put a square on the glass, align the corner vertex and one side with the glass vertex and one side respectively, and measure the distance between the other side of the square and the edge of the glass plate at 1m. The depth of the missing corner is measured from the original corner vertex inward along the angle bisector. 7 Inspection rules
7.1 Inspection classification
Factory inspection: Inspection items include thickness deviation, dimensional deviation, and appearance quality. Type inspection: Inspection items include all technical requirements of this product specified in this standard. 7.2 Sampling method
Carry out random sampling as specified in Table 4.
91~~150
151280
281~500
501~1200
1201~3200
7.3 Judgment rules
GB 4871
Sampling number
Number of unqualified pieces allowed
7.3.1 Judgment of a piece of glass: When all technical requirements of the glass meet the technical requirements of this standard, the glass is deemed to be qualified. Piece
7.3.2 Judgment of a batch of glass: When the number of unqualified pieces in any indicator is less than or equal to that specified in Table 4, the batch of glass is deemed to be qualified 8 Marking, packaging, transportation, storage
8.1 Glass is packaged in wooden boxes or containers (racks). Boxes (racks) should be convenient for loading and unloading and transportation. Wooden box packaging should comply with the requirements of JC/T513; containers (racks) should comply with the requirements of GB/T6382.1 and GB/T6382.2. 8.2 During transportation, the box head should face the direction of the vehicle's movement to prevent the box (rack) from tipping over and sliding. During transportation and loading and unloading, the box cover should face upwards and should not be placed upside down or tilted, and rain protection measures should be taken.
8.3 Glass should be stored in a dry and ventilated warehouse. Additional remarks:
This standard was proposed by the State Building Materials Industry Bureau. This standard was drafted by the Qinhuangdao Glass Research Institute of the State Building Materials Industry Bureau. The main drafters of this standard are Tan Jingya, Li Shaotang, and Wang Yulan. 366
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