GME 60323 Determination of Weave Density of Knitted Fabrics

Developed by General Motors Europe (GME), the “GME 60323 Determination of Weave Density of Knitted Fabrics” standard is an engineering material testing standard used to determine the weave or seam density of knitted and warp-knitted textile fabrics used in automotive interiors. This standard ensures that textile materials meet General Motors’ quality and performance requirements by providing a consistent procedure for measuring the number of loops, rows, and rows in a given fabric area. This standard is commonly referred to by testing laboratories as “Determination of Weave Density” or “Determination of Weave Density of Knitted Fabrics”.

The primary aim of the GME 60323 standard is to establish a uniform method for evaluating the structural density of knitted fabrics. Fabric density directly affects many performance characteristics, including:

• mechanical strength
• Dimensional stability
• Flexibility
• View
• Surface texture
• Durability
• Production consistency

General Motors suppliers can ensure that textile materials consistently meet design specifications and manufacturing requirements by applying a standardized measurement method.

The GME 60323 standard applies primarily to knitted textile materials used in automotive interiors. These include:

• Upholstery fabrics
• Door trim fabrics
• Ceiling fabrics
• Pole decking
• Packaging shelf fabrics
• Interior decorative knitted materials
• Laminated textile composites

The described method is designed for quality control, material adequacy, supplier approval, and production monitoring.

Knitted fabrics consist of interconnected loops instead of the vertical warp and weft threads found in woven fabrics. The GME 60323 standard measures the density of these loops by specifying the following parameters:

• Number of vertical loop columns
• Number of horizontal rows
• Stitch density in a specific measurement area

Measurements are typically taken along a specific length (e.g., 10 cm or another defined measurement length), depending on the material properties.

Typical laboratory equipment used in these tests includes:

• Textile counting glass or loop measuring glass
• Measuring ruler or calibrated scale
• Optical microscope (if needed)
• Fabric stretching device
• Illuminated examination table
• Digital image analysis system (optional)

Modern laboratories often use automated optical measurement systems to improve repeatability.

This testing method essentially follows these steps:

• The fabric is conditioned under standard laboratory atmospheric conditions.
• The sample is placed flat without being damaged.
• Representative measurement points are determined.
• The number of stitches and rows within the specified distance is determined.
• Measurements are repeated at multiple points.
• Average suture density is calculated.
• The results are compared to the engineering specification.

Taking multiple measurements helps account for natural variations throughout the fabric.

A typical assessment includes the following:

• Number of stitches per unit length
• Number of rows per unit length
• Stitch density
• Fabric homogeneity
• Local density variations
• Production consistency

Acceptance limits are determined by the materials engineering specification for the specific component.

Fabric density significantly impacts vehicle interior performance in automotive manufacturing because it affects:

• Appearance: Homogeneous density produces the following:
  • Consistent tissue
  • Homogeneous color perception
  • Improved visual quality
  • Improved surface smoothness.
• Mechanical performance: Correct stitch density improves:
  • Tensile strength
  • Tear resistance
  • Elastic recovery
  • Sewing performance
• Lamination quality: Many automotive fabrics are laminated to foam or backing materials. Consistent weave density supports:
  • Smooth adhesive penetration.
  • Improved adhesion
  • Reduced risk of separation.
• Production efficiency: Consistent fabric density ensures the following:
  • Easier cutting
  • Improved stitching precision.
  • Consistent pattern matching
  • Reduced production waste

Although developed for General Motors, similar fabric density ratings are widely used in the following areas:

• Automotive textile production
• Upholstery fabric production
• Interior trim suppliers
• Textile quality laboratories
• Research and development facilities
• Material certification laboratories

The GME 60323 standard complements several other General Motors textile standards, including:

• GME 60303 Test method for determining the thickness of flooring materials.
• GME 60314 Test method for determining the weight per unit area of ​​PVC coated flooring materials.
• GME 60317 Determination of yarn count and yarn density of woven fabrics.
• GME 60321 Determination of the proportions of plant fibers and rubber in flooring materials.
• GME 60325 Determination of tensile properties of housing coatings, sealants and sound insulation materials.

The advantages of implementing the GME 60323 standard are as follows:

• Standardized evaluation among suppliers.
• Improved product consistency
• Improved quality assurance.
• Improved material traceability.
• Reduced production variability
• Reliable supplier qualification
• Improved durability of interior textiles.

Modern vehicle interiors require fabrics that are attractive, durable, and consistent. Even small variations in stitch density can affect appearance, flexibility, comfort, stitching performance, and long-term wear. The GME 60323 standard provides a repeatable method to verify that knitted fabrics meet General Motors' engineering requirements before being used in manufacturing vehicles. By controlling fabric density, manufacturers can improve product quality, reduce defects, and ensure consistent performance throughout the vehicle's lifespan.

This standard is considered necessary for the following reasons:

• Ensures consistent material quality.
• It provides a neat appearance.
• Improves mechanical performance.
• It supports production processes.
• Ensures supplier consistency.
• Prevents premature wear.
• It supports material design and verification.
• Reduces warranty and quality issues.

Consequently, the GME 60323 standard is necessary because seam density of knitted fabrics is a fundamental property affecting appearance, strength, dimensional stability, manufacturability, and long-term durability. By providing a standardized method for measuring this property, this standard enables suppliers to produce interior textile components with consistent quality, reliable performance, and a uniform appearance across all vehicles.

For many years, our organization, with its competent and experienced staff, has been understanding the needs of its clients, providing the advanced testing services they require, and assisting them in the establishment, implementation, and improvement of management systems. Within this framework, we also provide testing services compliant with the GME 60323 standard.