GB/T 31902-2025 Inspection method for appearance defects on garment interlining English, Anglais, Englisch, Inglés, えいご
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ICS 59.080.01
CCS W 10
National Standard of the People's Republic of China
GB/T 31902-2025
Replaces GB/T 31902-2015
Inspection method for appearance defects on garment interlining
服装衬布外观疵点检验方法
(English Translation)
Issue date: 2025-02-28 Implementation date: 2025-09-01
Issued by the State Administration for Market Regulation
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Equipment and tools
6 Inspection conditions and operational requirements
7 Inspection methods
8 Inspection report
Annex A (Normative) Specific details of various defects
Annex B (Normative) Explanation of defect names
Inspection method for appearance defects on garment interlining
1 Scope
This document defines the terms and definitions for the inspection method of appearance defects on garment interlining, specifies the equipment and tools, inspection conditions and operational requirements, and describes the inspection principle and inspection methods.
This document applies to the inspection of woven interlinings, knitted interlinings and non-woven interlinings of various materials.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions 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 250 Textiles - Tests for colour fastness - Grey scale for assessing change in colour
GB/T 19022 Measurement management systems - Requirements for measurement processes and measuring equipment
GB/T 24117 Knitted fabrics - Description of defects - Terms
GB/T 24250 Woven fabrics - Description of defects - Terms
FZ/T 01076 Method for making composite test pieces of fusible interlinings
FZ/T 60034 Test method for powder shedding of fusible interlinings
3 Terms and definitions
The terms and definitions defined in GB/T 24250 and GB/T 24117 as well as the following apply to this document.
3.1
defect marking
tagging
method of marking appearance defects (by threading or tagging) during the appearance quality inspection of textile finished products
Note: Abbreviation for defect marking by threading (or defect tagging).
3.2
length allowance
additional length added to textile finished products due to the presence of defects
Note: Abbreviation for defect marking with length allowance, also known as length supplement.
3.3
linear defect
defect extending along the warp (longitudinal) or weft (transverse) direction with a width not exceeding 0.3 cm
3.4
strip defect
defect extending along the warp (longitudinal) or weft (transverse) direction with a width exceeding 0.3 cm (including block-shaped defects)
3.5
damage
breakage of 2 or more warp or weft (longitudinal or transverse) yarns, holes of 0.2 cm² or more, broken edges more than 2 cm from the selvage, floating threads of 0.3 cm or more, etc.
3.6
defect in base fabric
defects occurring in the base fabric of garment interlining during the production process
4 Principle
Under specified lighting conditions, visually inspect and count defects, mark defects by threading according to their shapes, and evaluate the surface appearance quality of garment interlining.
5 Equipment and tools
5.1 Fabric inspection machine: The tabletop forms a 45° angle with the vertical line. The upper and lower lampshades are equipped with 3-4 40 W ultraviolet light tubes and 3-4 40 W cyan daylight tubes respectively. The speed of the fabric inspection machine is 5 m/min - 30 m/min, equipped with a length measuring device.
5.2 Fabric inspection table: The width is greater than the fabric width, the length is longer than 1 m, and the tabletop is flat and smooth. 40W daylight tubes and ultraviolet light tubes are installed 1.0 m - 1.2 m above the tabletop, or north-facing natural light is used for illumination.
5.3 Straightedge or tape measure: Complies with the requirements of GB/T 19022, with a range greater than the measured size and a minimum graduation value of 1 mm.
5.4 Colour card: Grey scale for assessing change in colour in accordance with GB/T 250.
6 Inspection conditions and operational requirements
6.1 Inspection conditions
6.1.1 Lighting inspection.
For woven fusible interlinings, knitted fusible interlinings and non-woven fusible interlinings whose adhesive powder contains fluorescent agents: 3-4 40 W ultraviolet light tubes are used; For dark outer garment interlinings: 2 40 W cyan daylight tubes are used, with an illuminance not less than 400 lx; For others: 3-4 40 W cyan daylight tubes are used, with an illuminance not less than 750 lx.
6.1.2 The distance between the inspector's eyes and the fabric surface shall be 55.0 cm - 60.0 cm.
6.1.3 The maximum speed of the fabric inspection machine is 30 m/min.
6.2 Operational requirements
6.2.1 Inspection shall be carried out using a fabric inspection machine or a platform.
6.2.2 The inspection of garment interlining defects shall be based on the front side of the interlining (the side with grade marks is the reverse side).
6.2.3 During inspection, the inspector's line of sight shall be perpendicular or oblique to the fabric surface.
6.2.4 Measure the length of each defect on the fabric surface with a measuring tool (see 5.3).
6.2.5 In case of inconsistency between the inspection results of the fabric inspection machine and the platform, the platform inspection result shall prevail.
Note: The use of intelligent detection systems is advocated, which can improve inspection accuracy and efficiency.
7 Inspection methods
7.1 Inspection of local defects
7.1.1 Defect marking by threading method
7.1.1.1 For marking different defects, different coloured threads shall be threaded through the fabric selvage or marks shall be made to distinguish them. For minor defects and defects that do not affect the appearance of garments, if such defects are not visible after being covered with standard fabrics complying with FZ/T 01076, the defects shall not be marked by threading.
7.1.1.2 The provisions for marking bleached, light-coloured and medium-coloured interlinings by threading shall be in accordance with Table 1.
