The previous article shared with you the knowledge of the structure, characteristics and functions of the plastic tensile testing machine. I believe everyone has a further understanding of the plastic testing machine.
Next, in order to better operate the plastic tensile test machine, the second test machine will talk to you about how to sample the plastic tensile test machine and the corresponding operation methods.
1, Sampling
Plastic tensile tester test machine test sample should be a bar with a uniform width and thickness, the length should be at least 50mm (2in) longer than the distance between fixtures, the rated width of the sample should not be less than 5.0mm (0.20in) and not more than 25.4mm (1in), and the ratio of width and thickness is at least 8. A sample that is too narrow will amplify the strain condition and cracks at the edge of the sample.
Specific sampling is as follows:
1. When cutting samples, try to avoid defects such as defects that may cause premature breakage of the sample. The two sides of the sample should be parallel, and the width of the edge part should be less than 5% of the length of the sample between the two fixtures.
2. The thickness of the test sample should be constant. When the material thickness is less than 0.25mm (0.010in), the sample thickness should be less than 10% of the length of the sample between the fixtures; when the material thickness is greater than 0.25mm (0.010in) and less than 1.00mm (0.040in), the sample thickness should be less than 5% of the length of the sample between the fixtures.
3. If the material is suspected to be anisotropic material, two sets of samples should be prepared separately, and their long axes should be parallel and perpendicular to the direction of the anisotropic respectively.
4. When measuring the elastic tensile coefficient, 250mm (10in) should be used as the standard length of the sample. This length is used to minimize the impact of fixture sliding on the test results. When this length is not feasible, the length of the test area may be 100 mm (4 in) without affecting the test results. However, a length of 250mm should still be used in arbitration. When testing shorter samples, the test rate should be adjusted so that the strain rate is the same as the standard sample.
2. What are the operating methods of plastic tensile testing machines
1. After the plastic tensile testing machine is turned on, when the manual control box or microcomputer software cannot drive the machine to run, you should check whether the emergency stop button is in a stop state and turn on the computer.
2. After exiting the microcomputer software interface, the interval between the two times must not be less than 15 seconds when entering the interface again.
3. When installing specimens ascending or descending, pay attention to controlling the space and running speed of the upper and lower fixtures, otherwise half of the fixtures or sensors will be damaged.
4. The plastic tensile tester uses a national standard dumbbell cutting knife to install on the rubber sheet puncher, and cut the dumbbell shape according to the national standard 2mm rubber sheet.
5. After the upper and lower fixtures clamp the test piece, then the rubber tension machine has a large deformation (tracker) in the middle of the rubber test piece, with a gauge distance of 25mm. When clearing for tensile test, press the ‘run’ key to test instead of the ‘rise’ or ‘fall’ keys, otherwise the machine cannot determine the pull-off and shutdown signal, which will also cause damage to the fixture or sensor.
6. Non-trained personnel are prohibited from operating this machine, otherwise it will cause damage to the machine.
7. Do not disassemble this machine without authorization, otherwise there is a risk of electric shock or damage to the machine.
8. It is prohibited to use hard objects to collide with sensors, otherwise it will cause excessive deviation of sensor accuracy or damage.
3. What are the precautions during operation
1. Judging from the professional technology of running the test machine, it is important to keep the sample at the bottom of the instrument?
Different types of test machines need to use different fixtures. If they are ignored at this point, it will cause the test machine to not operate normally. If you replace the fixture, it is not only difficult to maintain the consistency of the current position, but it is also easy to damage the sensor.
. For the technology of operating the test machine, the test machine requires a lot of effort to complete, and this is a work that can be completed by most men.
2. What should you pay attention to when looking at the plastic tensile testing machine test?
Plastic tensile testing machine generally tests on plastics: tensile strength and modulus, bending strength and modulus. The two ends of the sample are clamped, one fixes are fixed, and the other is in the crossbeam. Remove the fixed fixture and pull the style until the fixture breaks, and then the crossbeam will automatically stop.
In this process, what we need to do is be careful and cautious, remember to be anxious and cause improper operation of the test machine and damage the test machine, which will be more than worth the loss.
or above is the explanation of the test machine on sampling, operating methods and operating precautions of plastic tensile testing machines. I hope to provide you with help and suggestions for better operation of plastic testing machines.
or above is the explanation of the test machine's main structure, structural characteristics and software functions of the plastic tensile test machine. If you want to know more about the test machine: principle, performance, parameters, usage, detection, operation, measurement, maintenance, technology, three-dimensional diagram, assembly diagram, structural diagram, schematic diagram, mechanical diagram, exploded diagram, circuit diagram, etc., welcome to chat with the test machine in the background, and the test machine can provide you with free consultation.
