How to test the tensile strength of tire rubber?

Testing the tensile strength of tire rubber is one of the important indicators for evaluating its physical properties. The following are the steps and methods for testing the tensile strength of tire rubber:

1、 Preparation stage

Sample preparation:

Take a small rubber sample from the tire and ensure that the size of the sample meets the testing requirements. Usually, the sample should have a standard shape (such as a dumbbell shape) to ensure uniform force distribution during the testing process.

The sample should avoid defects such as cracks and bubbles to ensure the accuracy of the test results.

Instrument preparation:

Prepare a material tensile testing machine that can apply stable tensile force and measure the deformation of the sample.

Select a suitable fixture (such as pneumatic fixture or self tightening eccentric roller fixture) to hold the sample according to its size and shape.

If testing is required at different temperatures, high and low temperature test chambers should also be prepared.

2、 Testing phase

Sample clamping:

Install the sample in the fixture of the tensile testing machine, ensuring that the fixture can firmly hold the sample and that the sample will not slip or deform during the stretching process.

Set parameters:

According to testing standards such as ASTM D412 or ISO 37, set the tensile speed of the tensile testing machine. Usually, the tension is increased at a certain rate per second until the sample fractures.

Start testing:

Start the tensile testing machine and apply tension to the sample. The test opportunity gradually increases the tension and records the tension deformation data.

Use video extensometers or other measuring devices to record the deformation process of the sample for subsequent analysis.

3、 Result analysis stage

Record data:

After the experiment is completed, record the maximum tensile strength (i.e. tensile strength) and elongation at break of the sample during the stretching process.

Data calculation:

Calculate the tensile strength of the sample based on the recorded data (usually measured in MPa). Tensile strength is the ratio of the maximum tensile force that a sample can withstand before fracture to the original cross-sectional area of the sample.

Result analysis:

Based on the test results, evaluate whether the tensile performance of the tire rubber meets the expected requirements. If the tensile strength is low, it may be necessary to adjust the rubber formula or production process to improve its performance.

4、 Precautions

Sample preparation: The preparation process of the sample has a significant impact on the test results. Therefore, when preparing samples, strict adherence to relevant standards should be followed to ensure the representativeness and accuracy of the samples.

Temperature control: If it is necessary to test the tensile strength of the sample at different temperatures, it should be ensured that the temperature control of the high and low temperature test chambers is accurate and stable.

Equipment calibration: Tensile testing machines and other measuring equipment should be calibrated before use to ensure the accuracy of test results.

Safety protection: When conducting tensile strength testing, attention should be paid to safety protection measures to avoid injury caused by fragments generated when the sample breaks.

In summary, testing the tensile strength of tire rubber requires following certain steps and methods, and paying attention to relevant matters to ensure the accuracy and reliability of the test results.