GMW 3217 Automotive Seat Fabric Abrasion Resistance Test

The “GMW 3217 Automotive Seat Fabric Abrasion Resistance Test” standard, developed by General Motors Worldwide (GMW), includes a test method used to evaluate the resistance of automotive seat fabrics to tearing and thread slippage. Abrasion occurs when threads begin to pull or loosen from the fabric structure in a cut, seam, or mechanically stretched area.

This standard is particularly important for woven automotive seat covers, as these materials are subjected to repeated mechanical stresses during seat cover manufacturing and throughout the vehicle's lifespan. The procedure is primarily designed for woven fabrics that are not laminated or contain laminate up to approximately 5 mm thick.

The primary purpose of the GMW 3217 standard is to determine whether a seat fabric can maintain its structural integrity when subjected to repeated bending and friction. A fabric with poor wear resistance may exhibit the following:

• Thread slippage
• Loose or pulled threads
• Fraying at the cut edges.
• Deterioration around the stitches
• Loss of sight
• Gradual weakening of the fabric structure

These effects can become particularly significant during the manufacture of seat covers, where the fabric is cut, sewn, folded, and processed, and during normal vehicle use.

The GMW 3217 standard, in principle, uses the Scott-type wrinkle-stretch abrasion pattern. The test equipment designed for this standard is specifically the Scott wrinkle-stretch tester, and laboratory accreditation documents define the GMW 3217 standard as a method for abrasion resistance.

The test sample is mounted on opposing fixtures. The fixtures bring sections of the fabric together and subject the material to repeated opposing motion. This produces a combination of folding, twisting, and friction that can cause the threads to move relative to each other. After a specified number of cycles, the fabric is visually evaluated for unraveling and thread slippage.

The exact dimensions of the sample, conditioning requirements, loading, and acceptance criteria are specified in the GMW 3217 standard. Generally, the testing process follows these steps:

• These samples are prepared according to the requirements of this standard.
• Samples are conditioned under the specified laboratory conditions.
• The sample is mounted on a Scott-type test fixture.
• The fixtures are positioned along the specified line.
• The specified movement, pressure, stroke, and test speed are applied.
• The required number of stretching/abrasion cycles are run.
• Samples are taken and visually examined.
• The amount of yarn breakage or yarn slippage is graded according to the applicable grading system.

Generally, a configuration is used with approximately 30 mm plus/minus 3 mm fixture separation, 50 mm stroke, 120 cycles/minute, and 1.000 cycles.

The primary assessment is the amount of apparent yarn movement or yarn breakage produced by the test. The rating is generally as follows:

• 10 = No noticeable unraveling or thread slippage.
• 8 = Light, non-disruptive unraveling / minimal thread slippage.
• 6 = Moderate unraveling or thread slippage.
• 4 = Significant unraveling or thread slippage.
• 2 = Excessive unraveling or thread slippage.

The grading system offers a practical way to distinguish fabrics exhibiting excellent resistance from those that may have unacceptable structural degradation.

The GMW 3217 standard is primarily related to automotive seat fabrics, particularly woven textile structures. The stated applicability of this standard covers woven fabrics without lamination and fabrics containing laminate up to 5 mm thick. Therefore, the method is useful in the following cases:

• Upholstery fabric material development
• Supplier qualification assessment
• Material verification
• Seat cover production approval
• Quality control
• Comparative evaluation of textile structures.

Abrasion resistance is an important property because a seat fabric can have acceptable tensile strength and abrasion resistance while still being susceptible to thread slippage and edge fraying. The GMW 3217 standard addresses this particular failure mode. This standard is considered important for the following reasons:

• Manufacturing durability: During cutting and sewing, textile edges and seams are subjected to mechanical processes. Poor thread breakage resistance can lead to fabric damage before the seat is even put into service.
• Maintaining the appearance: Loose threads and frayed areas can create visible imperfections on seat surfaces and around seams. Good thread break resistance helps maintain the intended appearance.
• Long-lasting durability: Automotive seats are subjected to repeated loading, movement, and friction. A fabric resistant to yarn shear can better maintain its structure during vehicle servicing.
• Supplier quality control: This test provides a standardized method for comparing different fabric structures and suppliers. Independent laboratories list this standard among their accredited textile testing capabilities.

Testing utilizes a Scott-type wrinkle-elasticity tester or equivalent device. Commercial equipment manufacturers specifically list the GMW 3217 standard among the standards supported by wrinkle-elasticity testers. These device specifications typically include:

• Controlled reciprocating motion
• Adjustable stroke length
• Controlled test speed
• Sample compression devices
• Defined sample loading
• Cycle counter
• Proper sample alignment

This equipment must be verified and calibrated according to the laboratory's quality system and relevant General Motors requirements.

The GMW 3217 standard should not be confused with other textile durability tests. Automotive seat fabrics are normally evaluated using a series of complementary tests. For example,

• GMW 3211 Resistance to stretching and permanent deformation.
• GMW 3208 Rotary abrasion test - Taber type
• GMW 3220 Laminate bond strength
• GMW 3326 Tear strength of textile materials by trapezoid method
• GMW 3347 Lint collection and retention properties of textile materials.
• GMW 3390 Flexibility of automotive upholstery materials.

These methods address different potential failure mechanisms and together provide a broader assessment of automotive textile performance.

The results are interpreted as follows:

• A high degree of abrasion resistance indicates that the fabric retains its yarn structure after the specified mechanical processing, and yarn movement is minimally visible.
• A low score indicates increased sensitivity to:
  • Thread breakage
  • Edge fraying
  • Structural relaxation
  • Visible deterioration
  • Potential damage in the suture area.

The acceptance limit may not be the same for every application. Therefore, the required result should be obtained not only from the test method but also from the relevant material specification, drawing, engineering requirement, or customer-specific requirement.

In conclusion, the GMW 3217 standard is an important automotive textile testing method for evaluating the tear and yarn slippage resistance of woven seat fabrics. The described method simulates repeated mechanical stretching and friction using a Scott-type wrinkle-elasticity tester and evaluates the resulting fabric degradation.

This test is valuable for automotive seat manufacturers and material suppliers because it helps identify fabrics that may deteriorate during seat cover production or prolonged vehicle use. Combined with abrasion, tensile, tear, seam, stretch, and other textile durability tests, this standard contributes to a comprehensive assessment of the quality and durability of automotive seat fabrics.

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 in accordance with the GMW 3217 standard.