Demand and test method analysis of tensile force and standard distance of rubber tensile testing machine
The tensile strength and calibration distance of rubber tension testing machine are two very important parameters in the process of using, tensile strength and calibration distance change, so the demand for these two parameters is very high, they directly determine the success or failure of the tension testing machine experiment and the quality, the following summary of the following requirements for tensile strength and calibration distance:
1. Equipment to accurately depict stress-strain curves
There is a close relation between the tension value and the standard distance in a tensile specimen. For example, the constant stress demand of the specimen measures the force value of the specimen stretched to a given elongation, while the constant stress demand measures the specimen stretched to a given standard distance of the stress.After the completion of the experiment, the precise stress-strain curve can reproduce the experimental process and clearly reflect the numerical value of each experimental segment. The rubber tension tester is convenient to calculate the large stroke of the project required by the experiment.
2. Data collection with high precision and frequency
Tensile rubber does not require a great deal of force, tension measurement scale does not require a great deal of force, so the demand for the precision of force value is higher.Usually, the experimental machine is required to find the force value with more than two decimal places.In addition, because testing rubber stretching function requires several tensile values in the stretching process, and the stretching experiment cannot be repeated, it is very important to accurately record the tensile force value of each experimental section in real time.
3. Accurate range measurement and recording equipment
The measurement of the sample distance is an important data for calculating the rubber elongation, so it is necessary for the rubber tension tester to accurately measure the strain variables of the sample in the rubber tensile test and record them down immediately.
4. Due to the large amount of rubber deformation during stretching, especially for latex products, the elongation rate can be as high as over 1000%. Therefore, it is necessary for the gripper to have a satisfactory stroke before the rubber sample breaks.
It is particularly important to measure the distance between bids.The method of distance scale measurement directly affects the accuracy of experimental value.The relation between the tension value and the scale distance in the tensile specimen is also very close.The technicians of Suzhou Force have summarized the standard distance measurement methods according to their practice for many years. The standard distance measurement is mainly divided into two methods: manual measurement and active measurement.
The first method is manual measurement.Manual measurement means that a ruler and two horizontal distance rods that can move vertically are set at the side of the gripper’s moving rod. During the stretching experiment, the change of the upper distance of the sample is investigated by eye power, and the two distance rods are manually controlled to synchronize with the distance on the sample, and the movement interval of the distance rod on the scale is recorded together.However, the numerical error of manual measurement method is relatively large.
The second method is active measurement.Compared with the manual method, the active measurement is more beneficial to the test of rubber stretching function.At present, the active distance measurement equipment of rubber tension testing machine in the market mostly adopts the touch sensor to measure the change of distance in real time, and the position of the device of the sensor mobile device is mainly divided into two positions of the device on the gripper and the sample.