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The test method standards state procedures for conducting a daily verification
of the Rockwell hardness machine. The intent of the daily verification is for the
user to monitor the reproducibility of the hardness machine between indirect
verifications. At a minimum, the daily verification should be performed each
day that hardness tests are to be made for each Rockwell scale that will be
used. It is recommended that the daily verification procedures be performed
whenever the indenter, anvil, or test force is changed to ensure that these
changes to the machine have not added error to the measurement due to
occurrences such as erroneous adjustments, misalignment, or poor condition
or cleanliness of the machine components.
Good Practice Recommendations• Before performing the daily verification tests, ensure that the testing
machine is working freely and that the indenter and anvil are seated
adequately. The indenter to be used for the daily verification must be the
indenter that will be used for testing.
• Whenever a Rockwell hardness machine fails a daily verification, the
hardness tests made since the last valid daily verification may be suspect.
• It is highly recommended that the results obtained from the daily verification
testing be recorded using accepted statistical process control techniques,
such as control charts. This type of monitoring can alert the user to
impending problems before the measuring capability of the hardness
machine becomes unacceptable.
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