Requirements for testing rubber for tensile testing machine

There are two data to be tracked during the rubber tensile test: the tensile force value and the gauge distance change. Therefore, the rubber tensile testing machine used to test the tensile properties of rubber must meet the following four requirements:

1. Stress-strain curve device.
There is a close relationship between the tensile force value and gauge distance in the tensile sample. For example, the constant elongation stress of a sample requires measuring the force value of the sample stretched to a given elongation, while the constant stress requires measuring the gauge distance from the sample stretched to a given stress. After the test is completed, the accurate stress-strain curve can reproduce the test process and clearly reflect the values ​​of each test section, making it easier to calculate the items required by the test.
2. High-precision and high-frequency data acquisition.
Tensile rubber does not require a large force, and the tension measurement range does not require a large force measurement, so the precision of the force value is required. Generally, the test machine is required to be able to obtain the force value with an accuracy of more than two digits after the decimal point. In addition, since detecting the tensile properties of rubber requires several tensile values ​​during the tensile process, and the tensile test cannot be repeated, instant and accurate recording of the tensile force value of each test section plays a very important role in the success or failure of the test.
3. Accurate gauge measuring and recording device.
The measurement of the gauge distance of the sample is an important data for calculating the elongation of the rubber, so the tensile test machine must accurately measure the strain value of the sample and record it immediately.

4. Large itinerary.
Because rubber deformation is very large when stretched, especially latex products, the elongation may be as high as 1000%. Therefore, before the rubber sample breaks, it is necessary to ensure that the clamp has sufficient stroke.