ISO 9969 specifies a test method for determining the ring stiffness of thermoplastics pipes. The test evaluates a pipe’s ability to resist deformation under external radial loads, providing information about its mechanical performance and suitability for installation conditions where external pressure may occur.

During the test, the system applies a controlled compressive load to a pipe specimen and measures its deflection, allowing calculation of the ring stiffness according to the standard. The results support quality control, product development, and compliance with application requirements.

In TramQA, the standard is implemented in two versions:

• One version includes inner diameter measurement using an encoder

• One version performs the test without inner diameter measurement

For more information about this test method, please visit the official ISO website.