As the core component of the connecting parts in medical equipment, the stress cracking resistance of the Ruhr connector directly affects the reliability and safety of the connector. The durability of the joint in complex stress environments can be effectively evaluated by conducting stress cracking tests using a Ruhr joint tester. This operating procedure is developed based on GB/T 1962.1-2001 "6% (Ruhr) Conical Connectors for Medical Devices" and in conjunction with our company's LE80369-D testing instrument operating examples. The experiment aims to evaluate the anti cracking ability of 6% (Ruhr) cone joint under specific stress conditions, ensuring that it will not crack due to stress during actual use, thereby ensuring the reliability and safety of Ruhr cone joint.

1、 Experimental equipment and materials

1. LE80369-D 6% Ruhr Cone Joint Comprehensive Tester
   This device integrates a stress application device, control system, and data acquisition system, which can accurately and real-time monitor the deformation and cracking of joints.

2. Standard steel joint
   Select steel outer cone or inner cone joints that comply with the provisions of 5.2.1 in GB/T 1962.1-2001, ensuring that the connection dimensions and tolerances meet the standard requirements.

2、 Experimental steps

（1） Joint assembly and stress loading

1. Drying treatment: Connect the tested cone joint to the standard steel joint (outer cone 10 #+13 # and inner cone 10 #+12 #), ensuring that both surfaces are dry and free of impurities.

2. Stress application: It is necessary to let it stand for 48 hours ± 1 hour under the conditions of a torque of 0.10N · m, an axial force of 27.5N, and a rotation angle not exceeding 90 degrees, to ensure that there is no cracking phenomenon. It is judged as qualified, otherwise it is judged as unqualified.

   
   

3. Disposable sterile injection needle: Place the assembled connector in an environment of 20 ℃± 5 ℃ for 24 hours.

4. Other medical devices: The idle time is extended to 48 hours to cover long-term use scenarios.

（3） Observation and recording of results

1. Observation tool: Use a microscope or magnifying glass (magnification ≥ 10x) to inspect the surface of the joint.

2. Judgment criteria:

• Qualified: The joint has no visible cracks, delamination, or deformation.

• Unqualified: There are any signs of stress cracking in any form, and the crack location, length, and shape need to be recorded.

3. Data recording: Detailed recording of stress loading parameters, settling time, environmental temperature and humidity, and observation results, generating stress time curves.

4、 Result analysis and improvement

1. Qualified product processing: The joints that pass the test can enter the next stage of quality inspection.

2. Analysis of non-conforming products:

• Crack localization: Determine the source of cracking through fault scanning or metallographic analysis.

• Process adjustment: Optimize material heat treatment process, adjust mold tolerances, or improve surface treatment process.

3. Report generation: Output a test report containing stress parameters and observation curve graphs, supporting ISO 80369 or GB/T 1962 standard certification.

This method is suitable for Ruhr connector testing of medical products such as syringes, infusion sets, and anesthesia equipment, and can cover the entire life cycle quality control from research and development to mass production. The automated data acquisition function of the LE80369-D Ruhr connector tester significantly improves detection efficiency, reduces human error, and provides a highly reliable stress cracking assessment solution for the medical device industry.