In the medical field,Needle tubes as thin as hair, such as injection needles and blood collection needles, carry the important mission of life and health.Needle tubes of different specifications (normal wall, thin wall, ultra-thin wall, extremely thin wall) have different requirements for rigidity performance. To ensure that the rigidity of injection needles meets the standard, GB/T 18457-2024 "Stainless Steel Needle Tubes for Manufacturing Medical Devices" specifies their rigidity. Shanghai Yingle's ZG-D medical needle tube rigidity tester is a professional equipment used to accurately detect the rigidity of stainless steel rigid straight needle tubes for various medical devices. It is suitable for various needle tubes such as intradermal needles, subcutaneous injection needles, and intramuscular injection needles, and is widely used in medical device manufacturers, quality inspection agencies, medical institutions, and other units. The following will provide a detailed introduction to the experimental steps of using this instrument for needle tube rigidity testing.

1、 Instrument preparation

One ZG-D medical needle tube rigidity tester

In the experiment, it is necessary to ensure that the tester is in normal working condition and check the various functions of the instrument, such as whether the displacement sensor is normal and whether the loading speed adjustment is sensitive. At the same time, prepare various stainless steel needle tubes for testing, with specifications ranging from 0.18 mm (34G) to 3.4 mm (10G).

IIExperimental steps

Install sample

1. Place the needle tubePlace the test needle tube smoothly on the needle holder of the ZG-D medical needle rigidity tester. The design of the needle holder can firmly support the needle tube, ensuring that the needle tube will not shake or shift during the testing process.

2. Adjust the spanAccurately adjust the span of the needle tube according to the values specified in Table 2 of GB 18457-2024. The accuracy of the span is crucial for the reliability of the test results, and different needle specifications may correspond to different span requirements, which must be strictly followed according to the standards.

3. Positioning force push rodEnsure that the end surface of the force push rod is located at the center of the span, and that the needle tube is perpendicular to the needle holder and push rod, with the centerline aligned. This step requires careful operation, as any deviation may affect the uniformity of force on the needle tube, thereby affecting the accuracy of deflection measurement.

Apply a certain prescribed force

1. Set loading speedAccording to the testing requirements, set the loading speed within the speed range of 1mm/min to 10mm/min. Different needle specifications or testing standards may have specific requirements for loading speed. Choosing a reasonable loading speed can better simulate actual usage situations and ensure the scientific and accurate testing results.

2. Apply force and measure deflectionAccording to the standard requirements, start the instrument and apply force to the needle tube. During the force application process, the instrument will automatically measure the deflection of the needle tube at the point of application. Deflection is the bending deformation of a needle tube under stress, and it is an important indicator for evaluating the rigidity performance of the needle tube.

record data

After the instrument completes the force application and deflection measurement, read and record the deflection value of the needle tube. The instrument adopts high-precision displacement sensors, which can accurately measure the deflection value of the needle tube with an accuracy of up to 0.001 mm. When recording data, it is necessary to ensure accuracy and correctness, so as to accurately evaluate the rigidity performance of the needle tube in the future.

The ZG-D medical needle tube rigidity tester has main functions such as high-precision testing, intelligent control, adjustable loading speed, and multi specification applicability. By strictly following the above experimental steps, the rigidity performance of various stainless steel needle tubes can be accurately evaluated, providing strong guarantees for the safety and effectiveness of medical devices.