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Ultrasonic Analysis

One of a variety of techniques use in predictive maintenance or enhanced FCAs.

monitor bearings at slower speeds.

Ultrasonic and vibration techniques are often used in tanded to support one another.


Types of Ultrasound
  • Airborne ultrasound
  • Structure-borne ultrasound


Purpose
The objective is:

Process
Listed below are the key steps in the process:

      A. Before Analysis
  • Identify low speed rotating machinery (under 60 rpm)
  • Determine the synergistic tandem use of ultrasonic and vibration techniques
  • Purchase the equipment or engage contractors
  • Schedule and execute the work
      B. During Analysis
  • A high frequency signal is sent and reflected by the component (asset) in order to detect early, small fatigue cracks or material structure defects / changes. 
  • Interpret the results
  • Apply condition grades
      C. After Analysis
  • Report to stakeholders
  • Make decisions
  • Determine CAPA's, if any
  • Determine next assessment interval

Applicable Conditions & Condition Grades
Listed below are the condition grades for this technology

      A. Lubrication problems
  • Over lubrication condtions
  • Under lubrication decisions.
      B.  Telltale stress wave problems
  • Coupling faults
  • Looseness
  • Damaged rotor bars
  • Damaged bearings
       C.  Leak detection
  • Steam-trap leakage (turbulent flow)
  • Pressure-safety-valve leakage
  • Reciprocating-compressor valve leaks
  • Electrical or coronal discharge leaks
  • Locating air leaks (turbulent flow)
      D.  Electrical dischagre
  • Detecting and locating sources of electrical discharge (Ionization)

Attributes
Listed below are some of the key attributes of motor current signature analysis:
  • It is a form of major maintenance
  • It is typically performed by qualified 3rd party contractors
  • It is conducted on variable intervals


Evaluation
Listed belows are some of the pros of ultrasonic inspection:
  • A comprehensive monitoring program usually includes ultrasonic analysis
  • Early detection can result in risk mitigation and cost savings
  • A cost effective filter  for identifying assets that should then be subject to vibration analysis.
  • Cost of ownership is lower compared to vibration analysis
  • Data is inexpensive to collect compared to some other technique
  • Training required to operate the tool is less demanding than vibration analysis
  • Good for optimizing of greasing programs
  • Prone to data contamination from various sound sources
Listed below are some of the cons of ultrasonic inspection:
  • Requires a capital investment in diagnostic eqiupment
  • Requires staff training


Candidate Assets
Listed below are some of the different types of candidate assets for ultrasonic analysis:

      Mechanical Assets
  • High and low Low speed rotating machinery
      Electrical Assets


      Other Assets



See other techniques:
See also:Compare with: