Boorim Textile SolutionsPilling, shrinkage, and tensile strength are three common fabric tests used to predict how a material may behave during use, washing, sewing, or manufacturing. They do not describe every quality issue, but they answer important questions: Will the surface look worn? Will the fabric change size? Will it be strong enough?
Knowledge pill: Pilling tests check surface wear, shrinkage tests check dimensional change, and tensile strength tests check resistance to pulling force. Together, they help buyers judge durability and production risk.
What is a pilling test?
Pilling is the formation of small fibre balls on the fabric surface. It happens when loose fibres work out of the yarn or fabric, tangle together, and remain attached.
Pilling tests simulate rubbing or abrasion during wear and washing.
Pilling risk is affected by:
- Fibre type
- Yarn twist
- Fabric construction
- Surface finishing
- Brushing or raising
- Blend composition
- Washing and abrasion conditions
Synthetic fibres such as polyester can form pills that are more persistent because the fibres are strong. Natural fibres may pill too, but pills may break away more easily depending on the fabric.
How pilling results are read
Pilling is often graded visually against standard photos or reference samples. A higher grade usually means better appearance after testing.
| Result direction | Practical meaning |
|---|---|
| High grade | Little visible pilling, better surface appearance |
| Medium grade | Some pilling, may be acceptable depending on product |
| Low grade | Heavy pilling, surface may look worn quickly |
Acceptable pilling depends on end use. A casual brushed fleece, luxury knit, uniform fabric, and upholstery material may have different expectations.
What is a shrinkage test?
Shrinkage testing measures how much fabric changes dimension after washing, drying, heat, steam, or relaxation.
Shrinkage can happen because fibres, yarns, fabric tension, and finishing stresses relax. Knitted fabrics often need careful shrinkage control because loop structures can change shape after washing.
Shrinkage tests usually compare measurements before and after a defined care process.
Common results:
- Lengthwise shrinkage
- Widthwise shrinkage
- Growth or extension
- Spirality or skew after washing
- Appearance change after laundering
Why shrinkage matters
Excessive shrinkage can cause:
- Garments becoming too small
- Twisted seams
- Poor fit after washing
- Mismatched panels
- Wrinkling or distortion
- Product claims from customers
Shrinkage tolerance should be agreed before ordering. A fabric used for relaxed casualwear may accept a different tolerance than a technical component.
What is a tensile strength test?
Tensile strength measures the force needed to pull a fabric until it breaks or reaches a defined point. It is important when fabric must resist tension during production, sewing, use, wrapping, converting, or installation.
Tensile strength can be tested in:
- Warp and weft direction for woven fabrics
- Course and wale direction for knitted fabrics
- Machine and cross-machine direction for nonwovens
- Length and width direction for films, tapes, and composites
The result may be reported as maximum force, breaking strength, elongation, or force at a specific extension.
Why tensile strength varies
Strength depends on:
- Fibre or polymer type
- Yarn count and twist
- Fabric density
- Weave, knit, or web structure
- Coating, lamination, or bonding
- Finishing process
- Moisture and conditioning
- Defects or weak points
A heavier fabric is not always stronger. Structure and material choice matter.
How to use these tests together
These tests answer different questions.
| Test | Main question |
|---|---|
| Pilling | Will the surface keep a good appearance after rubbing or wear? |
| Shrinkage | Will the fabric keep its size after washing, drying, or heat? |
| Tensile strength | Can the fabric resist pulling force during use or production? |
For many products, these tests should be combined with colour fastness, tear strength, abrasion, stretch recovery, seam performance, or functional testing.
Common mistakes
Common mistakes include:
- Comparing results from different test methods as if they are identical
- Testing only one direction of the fabric
- Ignoring washing method and drying method in shrinkage testing
- Judging pilling from a new fabric swatch only
- Assuming high GSM guarantees high strength
- Forgetting that finishing can change all three results
Fast recall
Pilling testing predicts surface wear, shrinkage testing measures dimensional change, and tensile strength testing measures resistance to pulling force. Test method, direction, washing condition, and end use all matter when interpreting results.