VIT 114 – Stiffness Tester Pneumatic

Testing Method

Test Procedure
A plunger with a 25.4mm (1 in) diameter pushes the fabric through a 38mm (1.5 in) diameter orifice for a distance of 57mm (2.25 in) in 1.7 seconds, and the maximum force exerted is recorded.

Use Range
This method is applicable to all fabric types, including woven, knitted, and nonwoven fabrics, regardless of fiber content.

Test Principle
The test uses a round loading head to push a flat, folded fabric sample into a platform hole. The maximum pressure exerted as the fabric passes through the hole determines the stiffness of the fabric.

Sample Preparation

• Cut sample plates to approximately 102mm x 204mm, ensuring no damage or defects.
• The sample should be folded once into 102mm x 102mm squares, with wrinkles flattened by pressing for 1 minute.
• Samples should be conditioned for at least 4 hours at 21±1°C with relative humidity less than 65±2%.

Test Procedure

1. Initial Check: Ensure the air source meets requirements, and verify that the load head is aligned with the test center hole.
2. Speed Adjustment:
   • Turn on the air supply, adjust the air pressure to 47 psi (0.324 MPa), and ensure it is maintained by pressing the knob.
   • Start the stopwatch when the loading head descends and stop it once the head stops moving. Ensure the time is 1.7 ± 0.3 seconds.
   • If needed, adjust the flow valve to meet the required speed.
3. Thrust Gauge Setup: Turn on the thrust gauge and clear its previous values.
4. Sample Testing: Place the flat sample onto the test platform and lower the loading head.
5. Recording Results: Once the loading head stops descending, read and record the maximum force displayed on the thrust gauge as the stiffness value.
6. Resetting: Pull the switch to return the load head to its starting position, remove the sample, and reset the thrust gauge to zero.
7. Repeat: Test four additional specimens following the same procedure, recording and averaging the stiffness values.
8. Final Setup: After completing the tests, turn off the power to the thrust gauge.

Pneumatic Cylinder
Compressed air is required for operation.