Ó 2007 Predictive Maintenance Technologies LLC
Newberg, OR
Elements of an Effective Predictive Maintenance Program



       
An effective Predictive Maintenance Program (PdM) is a process of five continually repeated steps:


       1.  Data Collection - Vibration data is collected from machines with
       portable data collectors, online acquisitions or a combination of
       both.

       2.  Data Processing - The data is loaded into a computer and
       analyzed with the aid of Predictive Maintenance Software.  The
       software provides access to the vibration data and data history. 
       Alarm functions are provided that check the data and report any
       readings that are over predetermined alarm levels.  Generally
       the PDM software turns the raw data into information about the
       vibration characteristics of the machine.

       3.  Data Analysis - At this stage, the information must be interpreted. 
       The interpretation requires knowledge about vibration characteristics
       and is preformed by trained specialists who are able to look at the
       vibration data and understand the overall readings and spectra
       graphs.

       4.  Repair Recommendation - Once the vibration patterns are
       understood, knowledge of the affected equipment must be
       considered.  For instance, can an individual bearing be replaced,
       or will the entire piece of equipment have to be removed for repair. 
       This step also compares the cost of a minor rebuild to that of a major
       rebuild. 

       5.  Implementation - The final task in the process is to consider the
       repair advice and other relevant factors such as cost of repairs,
       production requirements, budgets, ectů and make a decision.  It
       should be implicitly understood that when a decision is made it be
       implemented.  The appropriate decision may be inaction rather than
       action.  The "do nothing" alternative is often appropriate.  In such
       cases the work leading up the this decision has not been wasted, at
       least you know why you are doing nothing and are aware of the key
       factors that may change this strategy.