Sampling method and operating procedure of rubber material in tensile test
Rubber products have now become essential daily necessities in our daily life, such as tires, rubber pipes, conveyor belts, sealing rings and so on.Before these rubber materials can be made into rubber products, we will do a series of tests to prove that it is qualified before it can be used for production.The rubber tensile test is one of the comprehensive physical and mechanical properties test items.Here, Suzhou Ligao will teach you the sampling method and operation procedure of rubber material in tensile test:
One: The purpose of the experiment
Through the rubber material to do the tensile test, the detection of its tensile value when the maximum tension and the use of time when the break.Through these two test results to determine whether the quality of the rubber material is up to standard.
Ii. Principle of the test:
Apply two different directions to the rubber material, gradually and uniformly increase the tension, so that the rubber material deformation until the stress of fracture.
Iii. Sampling method of rubber materials:
1. Take out a section of rubber material and cut out the dumbbell sample, as shown in the figure below:
2. The cutting direction and tensile force direction of the sample are consistent with the drawing direction.
3. Before the tension test, the thickness, length and diameter of the sample within the standard distance shall be measured.
Iv. The testing instruments used in the test include:
1, the rubber material tensile test, we use the instrument for HF – 9003 single column tensile testing machine, it is the maximum tensile force of 5000 n (note: you can also use other tensile machine equipment, but to ensure that their maximum tension is not less than 5000 n, otherwise possible rubber materials under maximum tensile force without fracture).
2, the tension machine fixture is a wedge drawing fixture (wedge design can make the clamping force increases with the increase of the test sample stress, effectively avoid the phenomenon of slipping).
3. In addition to the above instruments, we also need a computer connected with the tensile testing machine, a printer, and a direct ruler to measure the sample length.
5. Specific operation steps of rubber tensile test:
1. Firstly, install the rubber sample on the fixture and set the stretching speed to 500mm/min.
2. Click to start the test and use the ruler to track the working line of the sample during the tensile test.
2. According to the test requirements, record the load when stretching to the specified elongation rate, the maximum load when the rubber is pulled out, the elongation at break and the time required for pulling out, and record the elongation curve.
3. When the specimen is broken, the measurement of the permanent deformation value shall be accurate to 0.5mm.
4. The final result of the experiment can be saved in the computer or printed out by the printer.
5. Remove the sample from the fixture after the test, and close the total power supply of the tension testing machine.
Vi. The rubber tensile test results are as follows:
“Graph of Test Results”
It can be seen from the above figure that the yield stress and tensile stress of this rubber tensile test are 10MPa, 20MPa, 500mm/min and 5min respectively.
Vii. Matters needing attention in tensile test:
1. No less than 3-5 tensile test samples.
2. The room temperature was about 23℃ at room temperature.
3. The test thickness is 2.0mm and the accuracy is plus or minus 0.5mm.
4. The test standard shall be GB2941 and GB528.