Vibration analysis for predictive maintenance of rotating machines

A method for determining the operational condition of a rotary machine, the method comprising the steps of,

• monitoring the machine under a baseline operating condition;
• collecting baseline vibrational data;
• calculating values from the baseline vibrational data for a preselected number of baseline parameters;
• calculating a first baseline operational indicator from the baseline parameter values;
• storing the baseline parameter values and the first baseline operational indicator in a memory location;
• monitoring the machine under a subsequent operating condition;
• collecting subsequent vibrational data during the subsequent operating condition;
• calculating values from the subsequent vibrational data for a preselected number of subsequent operating parameters;
• calculating a first subsequent operational indicator from the preselected number of subsequent operating parameter values;
• comparing the preselected number of subsequent operating parameter values to the preselected number of baseline parameter values wherein a difference between the subsequent parameter values and the baseline parameter values provides an indication of a mechanical problem exhibited by the machine;
• and
• comparing the first subsequent operational indicator to the first baseline operational indicator wherein a difference between the first subsequent operational indicator and the first baseline operational indicator provides an indication of a first type of mechanical problem exhibited by the machine.

A method for determining the operational condition of a rotary machine, the method comprising the steps of:

• monitoring the machine under a baseline operating condition;
• collecting baseline vibrational data;
• calculating values from the baseline vibrational data for a preselected number of baseline parameters;
• calculating a first baseline operational indicator from the baseline parameter values;
• storing the baseline parameter values and the first baseline operational indicator in a memory location;
• calculating a second baseline operational indicator from the baseline parameter values;
• storing the baseline parameter values and the first baseline operational indicator in a memory location;
• monitoring the machine under a subsequent operating condition;
• collecting subsequent vibrational data during the subsequent operating condition;
• calculating values from the subsequent vibrational data for a preselected number of subsequent operating parameters;
• calculating a first subsequent operational indicator from the preselected number of subsequent operating parameter values;
• calculating a second subsequent operational indicator from the preselected number of subsequent operating parameter values;
• comparing the preselected number of subsequent operating parameter values to the preselected number of baseline parameter values wherein a difference between the subsequent parameter values and the baseline parameter values provides an indication of a mechanical problem exhibited by the machine;
• comparing the first subsequent operational indicator to the first baseline operational indicator wherein a difference between the first subsequent operational indicator and the first baseline operational indicator provides an indication of a first type of mechanical problem exhibited by the machine;
• and
• comparing the second subsequent operational indicator to the second baseline operational indicator wherein a difference between the second subsequent operational indicator and the second baseline operational indicator provides an indication of a second type of mechanical problem exhibited by the machine.