Fabric inspection is a critical process in the textile industry, ensuring the quality and integrity of textile products. A comprehensive inspection system is essential for denim fabrics, which are widely used for their durability and versatility.
In the United States, a four-point grading system has been established as a standardized method for assessing the quality of denim fabrics.
This article aims to provide a comprehensive understanding of the American four-point grading system and its application to the inspection of denim fabrics.
How the 4-Point Grading System Works?
The U.S. four-point grading system helps manufacturers, suppliers, and consumers evaluate the suitability and value of denim fabrics for various applications.
- Deduction rules for the4-point system
Each type of defect is assigned a specific point value based on its severity
- Defect length less than 3 inches: 1 point deduction
- Defectlength between 3 inches and 6 inches: 2 points deduction
- Defectlength between 6 inches and 9 inches: 3 points deduction
- Defectlength greater than 9 inches: 4 points deduction
The grading for each defect is capped at 4 points. This means that even if there are multiple instances of the same defect per yard, it will only be graded as 4 points. Severe defects are automatically graded as 4 points.
For example, regardless of the size, all holes will be graded as 4 points.
- Here are some important considerations
- Defects within one inch of the fabric edge may not be counted.
- Defects that fall outside the normal control limits or are inherent to the nature of the fabric will not be penalized. For example, curling at the edges for plain knitted fabric.
- All holes, except needle holes, within a yard of fabric are graded as the highest point value.
- Unless specifically agreed upon, usually only the face side of the fabric is inspected.
- Other factors like color variations, skewness, and needle holes are not graded but can impact the overall downgrade classification based on severity.
The grading criteria for knitted fabrics is based on the total point deductions for 100 yards of fabric. For example, if a roll of fabric is 40 yards long and has a deduction of 6 points, the grading would be 6 x 100/40 = 15 points per 100 yards.
- Based on the grading result, the following rating standards can be used
- For fabrics with a width of 64-66 inches, if the total points are less than 50, it would be graded as first quality. If it exceeds 50 points, it would be graded as second quality.
- If the fabric width is greater than 64-66 inches, the grading limit increases proportionally to the width. For example, for a fabric width of 72 inches, the grading limit would be 50 x 72/64 = 56.25 points. Anything below this limit would be graded as the first quality, and anything above would be graded as the second quality.
To calculate the score for each roll of fabric, you can sum up all the point deductions. Then, based on the acceptance level, a grade can be determined. Different fabric widths would have different acceptance levels. The score per 100 square yards can be calculated using the formula: Score per 100 square yards = Total points x 3600/Yardage x Width.
Some factories state that a maximum of 40 points per 100 square yards is acceptable, however, in the apparel and textile industry, apparel brands and buyers set their standards of acceptable points.
However, we are different from ordinary manufacturers. ZEVA DENIM company has very high-quality standards for denim. We have set a maximum of 25 points per 100 square yards for our customers to get high-quality denim fabric with a low defect rate. Please click our quality page to learn more!
Advantages of the American Four-Point Grading System
The US four-point grading system provides several benefits to the denim industry and its stakeholders.
- Ensuring consistent denim quality
By implementing a standardized grading system, manufacturers and suppliers can ensure consistent quality levels for denim products. Consistency is critical to meeting customer expectations and maintaining a reliable supply chain.
- Protect consumers through standardized evaluation
The grading system provides consumers with a reliable benchmark for evaluating and comparing denim fabrics, ensuring they are getting the quality they want. It protects them from substandard or counterfeit products that may not meet their expectations.
- Enhances the Credibility and Reputation of Manufacturers and Suppliers
Adherence to the U.S. four-point grading system demonstrates a commitment to quality and professionalism. Manufacturers and suppliers who consistently produce high-quality Denim Fabric can gain credibility and enhance their reputation in the industry.
The American four-point grading system is an important tool for assessing the quality of denim. It helps manufacturers, suppliers, and consumers understand the level of quality associated with a particular fabric. Adherence to the grading system ensures consistent quality, protects consumers, and enhances the reputation of manufacturers and suppliers.
Fabric inspection plays a vital role in maintaining customer satisfaction and ensuring the integrity of denim products. By understanding and implementing the U.S. four-point grading system, the denim industry can thrive and maintain its leadership position in the global textile market.