The sealing performance of the centrifuge tube is an important factor affecting the accuracy of the experimental analysis results. Taking the testing process of the sealing performance of plastic centrifuge tubes as an example, a method for testing the sealing performance of centrifugal tubes is introduced, and the principle and equipment parameters of the testing process are briefly introduced, as well as the sealing performance of the testing equipment. Tester for verification. Corporate centrifuge tubes. Provide a reference for sealing performance.
The centrifuge tube is a commonly used experimental instrument, which is mainly used for the stratification and separation of liquid components in the tube. There are many types of centrifuge tubes, including large-capacity centrifuge tubes, small-capacity centrifuge tubes, and microcentrifuge tubes. Depending on the capacity, there are also glass centrifuge tubes, plastic centrifuge tubes, and steel centrifuge tubes. . Most centrifuge tubes come with caps. If the compatibility between the cap and the centrifuge tube is poor and the seal is not tight, it is easy to cause the liquid in the centrifuge tube to overflow and leak, corrode the centrifuge, affect its service life, and contain volatiles. As far as the liquid of the sexual component is concerned, it is also easy to cause volatilization and dispersion loss, which affects the content of each component in the centrifuge tube, resulting in deviations in the experimental results. Therefore, there should be a good seal between the lid and the centrifuge tube.
Test methods and test equipment
At present, there is no standard for testing the sealing performance of centrifuge tubes in China. In this paper, the sealing performance of the centrifuge tube is tested according to the principle of negative pressure test. The commonly used testing equipment for the sealing performance testing of flexible plastic packaging and packaging containers is a sealing test machine.
Test samples and experimental procedures
Test principle: The basic test principle of this device is the principle of negative pressure method, that is, the external environment where the sample is located reaches a certain degree of vacuum through vacuuming, so that a certain pressure difference is formed between the interiors. Outside the sample, if the sample is poorly sealed, the internal gas will escape from the inside of the sample along the poor seal under the action of the pressure difference. Tightness is determined by observing whether there are continuous air bubbles on the surface of the sample in water or the behavior of the sample shape recovery after the vacuum is released. Test samples and test procedures
testing sample:
This article uses a certain brand of plastic centrifuge tubes as test samples. The materials commonly used in the production of plastic centrifuge tubes are polyethylene, polycarbonate, polypropylene, etc., among which polypropylene plastic centrifuge tubes have better performance.
Experimental procedure:
(1) Immerse the sample of the centrifuge tube to be tested in the water in the sealing tank of the device, and cover the sealing cap.
(2) Set parameters such as vacuum degree and pressure holding time, turn on the vacuum pump, and press the start button on the equipment panel to start the test.
(3) Observe whether there are continuous bubbles on the test surface during the process of vacuuming or maintaining pressure.
Test Results and Analysis
In this paper, the sealing performance of three centrifuge tube samples was tested, and the leakage of the three samples were -65.1 KPa, -63.9 KPa and -70.3 KPa, respectively. The sealing performance of the centrifuge tube is an important factor affecting the smoothness of the test and the accuracy of the test results. This paper introduces a simple method to verify the sealing performance of plastic centrifuge tubes, that is, using a seal tester to test the sealing performance of plastic centrifuge tubes. The test process is simple and the equipment is easy to operate.
