Ring Stiffness Testing    ISO 9969 - Thermoplastics pipes ? Determination of ring stiffness  ASTM F894 - Polyethylene (PE) Large Diameter Profile Wall Sewer and Drain Pipe

Standard ISO 9969 is a standard issued by the ISO - International Organization for Standardization.  ASTM F894 is a standard issued by the ASTM - American Society for Testing and Materials . The standards cover a wide range of pipe information such as measurement, terminology, classifcations and testing methods.   Application In Ring Stiffness Testing the pipes compressive properties are measured. As noted in ISO a preload shall be first applied prior to testing. Once the preload force has been applied, the test can be started. In ASTM F894 the Ring Stiffness Constant requires the pipe to be deflected to 3% deflection.  Both methods require a preloading of the specimen prior to the actual compression or ring stiffness testing.   Accessories Both the ISO 9969 and ASTM F894 states that fixed, parallel compression plates are to be used.   Fixed parallel compression plates    Pipe deflection meter for deflection measurements   Large pipe ring stiffness testing require larger plates and compression zones.     Worlds largest ring stiffness testing machine