Set the Tester
Readings within 10–90% of full scale; speed 300 ± 10 mm/min.
Knit Fabric Manufacturer Since 2009 · China
TEST METHOD · GB/T 19976 · ISO 13938-1
Bursting Strength of Knit Fabric
Bursting strength shows how much force a knit takes before a ball or a diaphragm pushes through it. We test with the steel ball method (GB/T 19976, similar to ASTM D6797); many European specifications cite the hydraulic ISO 13938-1.
Specimens cut from the bulk lot.
Our method
GB/T 19976 steel ball
US equivalents
ASTM D6797 / D3786
Units
N (ball) · kPa (hydraulic)
01
What This Test Measures
Knits stretch in every direction, so a bursting test, which pushes against the fabric from one side like an elbow or knee, describes how they fail in use.
Ball methods (GB/T 19976, ASTM D6797) report force in newtons; diaphragm methods (ISO 13938-1 hydraulic, ASTM D3786) report pressure in kilopascals. The two cannot be converted.
02
How We Run It in Our Lab
Our technicians follow a written work instruction for this method.
Our lab runs the steel ball method; hydraulic testing is arranged with third-party labs when an order requires it.
Choose the Ball
A 25 mm or 38 mm polished steel ball, as agreed.
Clamp and Burst
The specimen is clamped flat, back facing the ball, and burst.
Report
Peak force in newtons; mean of at least five specimens.
03
Test Conditions
Key settings. Write the method and procedure in your specification.
| Parameter | Setting |
|---|---|
| Method | GB/T 19976-2005, steel ball |
| Ball | 25 or 38 mm |
| Speed | 300 ± 10 mm/min |
| Specimens | At least 5 |
| Equivalent methods | ASTM D6797 / D3786 (US) · GB/T 19976 (China). Compare methods → |
04
Results for Your Order
Ask us for results for the selected fabric, shade and test conditions. Acceptance values for your order are agreed in writing.
05
Writing This Test into Your Specification
Match Method and Unit
Newtons belong to ball methods; kilopascals to diaphragm methods.
Bursting, Not Tearing
Some templates call ISO 13938 “tear resistance”. It is a bursting test.
State the Ball Size
For ball methods, state 25 mm or 38 mm.
06
Questions About GB/T 19976 · ISO 13938-1
Is ISO 13938 a tear test?
No. ISO 13938-1 and -2 are bursting tests with a hydraulic or pneumatic diaphragm. Tear tests such as ISO 13937 are mainly for woven fabrics.
Can I convert newtons from a ball burst test into kPa?
No. The methods load the fabric differently, so there is no reliable conversion.
Why test knits for bursting rather than tensile strength?
Knits stretch in all directions and fail under multi-directional load; a bursting test reproduces that load.