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The inspection standards for color-coated steel coils can be viewed from the aspects of size, coating, surface inspection, and labeling requirements.
1) Prepainted Steel Coils Of Specifications
The width error is ±2mm, the incision is straight, the cut surface is neat, and the thickness tolerance is ±0.03mm.

2) Prepainted Steel Coils Of Coating
The type of coating meets the contract requirements, the color of the coating is uniform, there is no obvious color difference, and the thickness of the coating meets the contract requirements.

3) Surface inspection
The coil surface is flat, without obvious unevenness, warped surface, deformation, clean surface, no oil pollution, no surface bubbles,
shrinkage cavities, leakage of coating, and other defects that are harmful to use, and the defective part of the steel coil does not exceed 5% of the total length of each coil, with no obvious scratches Scratches, bumps, or scars.

4) Label Requirements
The paper strip or other material products on the package must have the product name, specification, manufacturer, etc.,
the packaging mark is eye-catching, and firm and the handwriting is clear.
The supplier's name or supplier trademark, standard number, grade, specification, weight, etc. must be marked.
The packaging mark shall indicate the identification number that can track from the steel to the smelting,and the quality certificate shall indicate the name of the buyer,the contract number, the product name, the standard number, the specification, the grade, the identification number,the weight and the number of pieces that can be traced from the steel to the smelting, production date, and delivery date,and the mark must indicate the weight of the substrate coating, the type of finish, and the color.

Explanation:
The first section describes the specifications for the size of the prepainted steel coils. The width should have an allowable error of ±2mm, the cutting line should be straight, the cut surface should be neat, and the thickness tolerance should be ±0.03mm.
The second section focuses on the coating of the steel coils. It should meet the requirements specified in the contract, have a uniform color without any obvious differences, and the thickness of the coating should comply with the contract specifications.
The third section discusses the surface inspection of the coils. The surface should be flat without any visible unevenness, warping, or deformation. It should also be free from oil contamination, surface bubbles, shrinkage cavities, or any other defects that could affect the usability. The defective portion of each coil should not exceed 5% of the total length, and there should be no noticeable scratches, bumps, or scars.
The fourth section outlines the labeling requirements for the steel coil packaging. The package should have clear and conspicuous markings that include the product name, specification, and manufacturer. Additionally, the packaging mark should include the supplier's name or trademark, standard number, grade, specification, weight, and an identification number that can trace the steel to its smelting origin. The quality certificate should include the buyer's name, contract number, product name, standard number, specification, grade, identification number, weight, number of pieces, production date, and delivery date. The mark should also indicate the weight of the substrate coating, type of finish, and color.
Rewrite:
Inspection Standards for Color-Coated Steel Coils
Size Specifications
The width of the prepainted steel coils must have an allowable error of ±2mm.
The cutting line should be straight and the cut surface should be neat.
The thickness tolerance is ±0.03mm.
Coating Requirements
The type of coating applied must meet the specified requirements in the contract.
The color of the coating should be uniform without any noticeable differences.
The thickness of the coating should comply with the specifications laid out in the contract.
Surface Inspection
The surface of the coils should be flat and free from visible unevenness, warping, or deformation.
There should be no oil contamination, surface bubbles, shrinkage cavities, or any other defects that could negatively impact their use.
The defective portion of each coil should not exceed 5% of the total length, and there should be no noticeable scratches, bumps, or scars.
Labeling Requirements
The packaging must include clear and conspicuous markings with the product name, specification, and manufacturer.
The packaging mark should also feature the supplier's name or trademark, standard number, grade, specification, and weight.
An identification number that can trace the steel to its smelting origin should be indicated on the packaging.
The quality certificate should include the buyer's name, contract number, product name, standard number, specification, grade, identification number, weight, number of pieces, production date, and delivery date.
The mark should also clearly state the weight of the substrate coating, type of finish, and color.