A summary of the thickness, weight, and tensile test methods of conventional nonwoven fabrics

1. Thickness

Use the production line thickness meter for testing.

The standard stipulates: when used for conventional non-woven fabrics, the load on the presser foot should reach 0.5Kpa. Place the sample on the reference plate under no tension, and ensure that the sample faces the center of the presser foot for 10s , Record the reading. Use the same method to test the other 9 samples. (Only emphasizing the test method, not emphasizing the sampling standard, currently sampling and testing according to actual usage)

Current test: (The method is determined, not participating in the non-woven fabric humidity control process)

Wide non-woven fabric: Take 5 points in the CD direction of the non-woven fabric to test the thickness. In the specific test, since the non-woven fabric is a compact type, the reading time is generally about 3s (different from the 10s specified by GB). The left and right sides of the MD direction are sampled at regular intervals for testing. The specific sampling distance is generally set at about 20cm, each The sampling point attachment is tested more than twice, and 5-10 points are respectively selected for testing.

Narrow-width non-woven fabric: CD-direction non-woven fabrics take one or two points on the left, middle and right respectively to test the thickness. The MD direction sampling test method is basically the same as that of the wide-width.

2. Weight

Currently, manual sampling + calculation is adopted.

Manual sampling:

According to the given non-woven fabric sample, take one piece (≥1 piece) of 10cm*10cm non-woven fabric sample from the left, middle and right sides of the wide non-woven fabric in the CD direction. At present, there is no sampler, and the method of measuring with a steel ruler is adopted. Take 2 (≥2) non-woven fabric samples on both sides of the MD direction for testing and comparison. (Sampling rules are not emphasized) In the case of a large difference in the weight of the non-woven fabric, the number of samples can be appropriately increased to indicate its standard deviation (if necessary).

Narrow-width non-woven fabric samples are tested on the left and right sides in the CD direction. The sampling rules in the MD direction are the same as those for the width. For non-woven fabrics with large differences in uniformity, the number of samples can be appropriately increased.

Calculate the weight:

Calculate the non-woven fabric weight per square meter based on the actual sampling area and the weighed weight

Difference with GB:

In the case of no round knife cutter, a square mold can be used. The GB stipulates that the circular or square cutting area is at least 50000mm2, and at least three samples are cut. The area of the sample can be reduced according to the actual situation. Humidity control for 24 hours, these are still quite different from the current current methods.

When calculating the coefficient of variation, at least 5 samples are required.

3. Stretch

Currently, Meister Microcomputer-controlled electronic universal testing machine is used to test the tensile tension. The relevant parameters are as follows:

Model: CMT6502

For specific sampling, cut the non-woven fabric into 10cm*1.5cm specifications in the CD and MD directions, and use a tensile testing machine to perform a tensile test, and take the maximum force as the tensile tension value. Among them, the initial distance between the upper and lower bars is 6cm, and the calculated breaking elongation is the ratio of the difference between the two before and after the non-woven fabric is broken to the initial distance between the upper and lower bars (the elongation at break is different from the system calculation)

The modulus of elasticity (not specified in the national standard) refers to the slope between the straight line represented by the force and displacement at the beginning of the stretching of the non-woven fabric, which reflects the degree of deformation of the non-woven fabric under a certain pressure or tension. Can be used as a qualitative reference for corrugated cloth.

At present, there is a difference between the sampling specifications and GB. GB stipulates that it is 200mm*50mm. There are also restrictions on experimental testing equipment, which is difficult to get through according to GB regulations. The experiment speed is 100mm/min, the same as GB. The method of determining the tensile strength is the same.