Standard Test Method for Bursting Strength of Textile Fabrics -Diaphragm Bursting Strength.(Ball Bursting)

1. ASTM D3786 / D3786M-18
Standard Test Method for
Bursting Strength of Textile Fabrics -
Diaphragm Bursting Strength
Tester Method
ASTM D3786/D3786M-13

2. Principle
 Specimen is clamped over an expandable
diaphragm
 the diaphragm is expanded to the point of
specimen rupture.
 The difference between the total pressure
required to rupture the specimen and the
pressure required to inflate the diaphragm is
reported as the bursting strength.
ASTM D3786/D3786M-13

3. Scope
 Applicable to knits, wovens, or nonwovens
 Mainly for knits and stretch wovens (tensile
tests not appropriate)
ASTM D3786/D3786M-13

4. Definition
Bursting Strength
 The force or pressure required to rupture a
fabric by distending it with a force, applied
perpendicular to the plane of the fabric.
 Note that machine and cross-machine direction
are not differentiated.
ASTM D3786/D3786M-13

5. Apparatus
 Flexible diaphragm
 Inflation:
 Hydraulic (fluid; 96% USP glycerin)
 pneumatic (gas; air)
 Pressure control & measurement
 31 ±0.75 mm diameter circular clamp
ASTM D3786/D3786M-13

6. Sampling
 Lab Sample
 1 m full-width
 (discard first meter of roll)
 Test Specimens
 Avoid selvage (10% of fabric width)
 10 specimens
 125 mm (5 in) circles or squares
 Different warp/course and fill/wale
ASTM D3786/D3786M-13

7. Conditioning
 Refer to ASTM D1776
 Bring specimens to moisture equilibrium before
testing
 Test in standard atmosphere
ASTM D3786/D3786M-13

8. Procedure
 Clamp specimen smoothly and securely
 Apply pressure until specimen bursts
 Release diaphragm pressure and remove
specimen
 Determine pressure required to distend
diaphragm only to the same height as used to
burst specimen
ASTM D3786/D3786M-13

9. ASTM D3786/D3786M-13

10. Calculation
 Subtract tare pressure from burst pressure for
each specimen
 Average the 10 specimens
 Average lab samples in each lot if applicable
ASTM D3786/D3786M-13

11. Report
 Test method used
 Material tested
 Individual and average bursting strengths (kPa or
psi)
 Type of tester
ASTM D3786/D3786M-13

12. Calibration
 Standard aluminum sheets
 Test monthly (minimum)
 5 specimens
 ±5% of indicated strength
 Self-calibrating instruments
ASTM D3786/D3786M-13

13. Calibration Foil
ASTM D3786/D3786M-13

14. Troubleshooting
 Examine clamp for wear and distortion
 High-stretch fabrics may need to be (uniformly)
pre-stretched before clamping
 Eliminate specimen creases and folds before
clamping
ASTM D3786/D3786M-13

15. Troubleshooting
 If pressure stops before specimen bursts, report
“stretch exceeds dimensional limitations of the
tester.”
 If specimen slips from clamp, discard and retest
ASTM D3786/D3786M-13

16. Troubleshooting
 Burst (on pneumatic tester) should take 15-25
seconds.
 Preliminary trials may be needed to set control
valve correctly
ASTM D3786/D3786M-13

17. Troubleshooting
 Critical differences
 Spun Yarns in Circular Knit: ±6.0%
 Filament Yarns in Tricot Knit: ±2.0%
ASTM D3786/D3786M-13