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Maintaining the Accuracy of Charpy Impact Machines



D P. Vigliotti, Thomas A. Siewert, Christopher N. McCowan


The quality of the data developed by impact machines tends to degrade over time, due to the effects of weear and vibration that are inherent in the test. This is the reason that impact standards specify periodic direct and indirect verification tests. Each year, we provide reference specimens for indirect verification of over 800 machines around the world. From evaluation of the absorbed energies and the fractured specimens, we are able to deduce the origin of energies that are outside the allowed ranges, and report these observations back to the machine owners. This report summarizes the basis for the observations and will allow, it is hoped, machines to be maintained at higher levels of accuracy.
ASTM Special Technical Publication


absorbed energy, Charpy V-notch, impact test, machine repair, misalignment, verification testing, worn anvils


Vigliotti, D. , Siewert, T. and McCowan, C. (2000), Maintaining the Accuracy of Charpy Impact Machines, ASTM Special Technical Publication, [online], (Accessed June 14, 2024)


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Created May 1, 2000, Updated February 17, 2017