Overview
ISO 13936-1:2004 - "Textiles - Determination of the slippage resistance of yarns at a seam in woven fabrics - Part 1: Fixed seam opening method" specifies a laboratory method to measure the resistance of woven-fabric thread systems to yarn slippage at a sewn seam. The standard defines specimen preparation, sewing (lockstitch type 301), test-fixture dimensions and alignment, test-machine settings and reporting rules so results are reproducible and comparable between laboratories.
Key topics and technical requirements
- Test principle: Compare force/extension curves from a seamed and an unseamed specimen (grab test) on a constant-rate-of-extension (CRE) tensile machine; determine the force required to produce a specified seam opening.
- Test machine and settings: CRE machine with metrological confirmation per ISO 10012; constant jaw-separation rate nominally 50 mm/min (±10 %); gauge length 100 mm; data acquisition frequency at least 8 s−1 when computerized.
- Clamping and specimen area: Fabric clamped area nominally 25 mm × 25 mm (with allowed methods to achieve this); jaws must hold without cutting or weakening the fabric.
- Sewing and specimen preparation: Seams use stitch type 301 (single-needle lockstitch). Sewing thread, needle and stitch density are adjusted for the fabric under test; paired specimens (seamed and unseamed) are cut so tests are performed on equivalent threads and areas.
- Number of tests and limits: Five pairs of specimens are tested in each direction (warp and weft). Forces are recorded; if the target seam opening cannot be reached at or below 200 N, report as “greater than 200 N.” Fabric or seam failure is reported as “fabric breakdown” or “seam breakdown” with the force at failure.
- Data handling: Procedures for chart-recorded and computer-recorded force/extension curves are given, including how to compensate for initial straightening and how to calculate mean results.
Practical applications and users
- Quality control and product development: Apparel, home textiles and technical textile manufacturers use the method to evaluate seam performance and durability under seam-opening loads.
- Material selection and sewing system validation: Helps manufacturers choose thread, stitch type and seam allowance combinations that minimize seam slippage in woven fabrics.
- Laboratory testing and conformity assessment: Textile test labs and R&D teams use ISO 13936-1 to produce standardized, comparable slippage-resistance data for specifications, complaints handling and performance claims.
Related standards
Keywords: ISO 13936-1:2004, seam slippage, slippage resistance, fixed seam opening method, textiles testing, CRE machine, stitch type 301, seam opening, seam breakdown.