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Condition Monitoring

  • Condition monitoring (or, colloquially, CM) is the process of monitoring a parameter of condition in machinery (vibration, temperature etc.), in order to identify a significant change which is indicative of a developing fault. It is a major component of predictive maintenance. 
  • The use of condition monitoring allows maintenance to be scheduled, or other actions to be taken to prevent failure and avoid its consequences. 
  • Condition monitoring has a unique benefit in that conditions that would shorten normal lifespan can be addressed before they develop into a major failure. 
  • Condition monitoring techniques are normally used on rotating equipment and other machinery (pumps, electric motors, internal combustion engines, presses),
Condition monitoring techniques
  • Vibration and shock pulse data measured from all machinery. On the spot analysis and interpretation of results.
  • Thermo graphic inspection of all electrical and some critical mechanical systems.
  • Pressure and vacuum leak detection using passive ultrasonic frequency methods.
  • Thickness measurement of critical machinery systems.
  • Main and auxiliary engines performance test and power balance analysis.Detailed machinery health assessment report.
Benefits:
  • Help maximize the availability of your critical and auxiliary machinery
  • Simplify maintenance and reduce maintenance costs
  • Give an early indication of possible problems
  • When a machine is operating properly, the vibration is small and constant, however, when faults develop and some of the dynamic process in the machine changes, there will be changes in vibration spectrum observed.
When a fault takes places, some of the machine parameters are subjected to change. The change in the machine parameters depends upon the degree of faults and the interaction with other parameters.
In most cases, more than one parameter are subjected to change under abnormal condition.
Condition monitoring can be carried out when the equipment is in operation, which known as on-line, or when it is off-line, which means when it is down and not in the operation.
While on-line, the critical parameters that are possible to monitor are speed, temperature, vibration, and sound. These may be continuously monitored or may be done periodically. Off-line monitoring is carried out when the machine is down for whatever reason.
The monitoring in such would include crack detection, a thoroughly check of alignment, state of balancing, the search for tell-tale sign of corrosion, pitting, and so on.
Vibration signals are the most versatile parameters in machine condition monitoring techniques.
Periodic vibration checks reveal whether troubles are present or impending. Vibration signature analysis reveals which part of the machine is defective and why.
 Although a number of vibration analysis techniques have been developed for this purpose, still a lot of scope is there to reach a stage of expertise.

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