*Diagnostic TechniquesObjective:Why do you utilize Diagnostic Techniques?How we can apply Diagnostic Techniques in the equipment or assets of the company.

*Diagnostic Techniques.We learned that an effective maintenance program incorporates three types of inspections, operational inspection, replacement inspections, and those inspections that necessitate an equipment shutdown. In all three of these inspections classes, there often is the need to utilize diagnostic techniques in order to predict maintenance by identifying a particular disorder and its magnitude. The data needed in order to diagnose the condition of equipment includes overall vibration level, axial position indication, bearing temperatures, speed, noise level, differential expansion, and others.

*Diagnostic Techniques.VIBRATION ANALYSIS.The use of vibration analysis in order to learn about a individual machine's condition is becoming increasingly important in connection with those inspections introduced in a PM program.Periodic checks of overall vibration and velocity levels at selected bearings located in equipment establish a point where action is to take place.

*Diagnostic Techniques.Setting Up the Vibration Measurement Program.The following points should be adhered to in order to have a viable vibration measurement effort:Select the machines to be included in the program.Select and mark check points.Select the periodic check interval.Establish vibration limits.Conduct a vibration analysis of each select machine.Begin a data bank and maintain records of the equipment.

*Diagnostic Techniques.PROCESS PARAMETER MONITORINGSeveral of the parameters relating to the efficient operation of a facility or system can be monitored. Electrical Measurements.Sound Intensity.Hydraulic and Pneumatic testing.Temperature Monitoring Including Thermograph.Tribology.Visual Inspection with Dimension and Motion Pattern Monitoring.Shock Pulse Measurement.

*Diagnostic Techniques.NONDESTRUCTIVE TESTING.There will be numerous occasions, especially in connection with mechanical equipment, where the PM inspector will need to check a component for flaws, cracks, and so on, due to fatigue, misuse, or wear. Usually it is essential that the component be inspected with out destroying it. Several nondestructive testing and inspection techniques are available. The most important of these are:Magnetic-Particle.Radiographic.Sonic and Ultrasonic.Fluorescent penetrant.

*Diagnostic Techniques.INSTRUMENT AVAILABILITY.Several of the instruments are costly and may be difficult to acquire by the small or medium sized maintenance department. This should not discourage their use in connection with diagnostic procedures used in conjunction with preventive maintenance. Frequently, these instruments are already being used in the inspection department. If so, it should be a simple matter to have them periodically loaned to maintenance.

*Diagnostic Techniques.TRAINING FOR DIAGNOSTIC:The diagnostic technician is a highly skilled individual who has had extensive training and experience. The availability of this type of technician, especially in smaller plants, is limited. Those technicians who perform diagnostic will find that it is necessary to continually update themselves in order to stay abreast of the ever increasing new technologies characteristic of modern facilities and equipment.

*Diagnostic Techniques.Summary

The ability to diagnose the condition of key equipment is the heart of predictive maintenance. As production equipment becomes more sophisticated, so the instruments needed to diagnose it becomes more complex. It is essential that technicians associated with predictive maintenance receive regular training in the use of modern instrumentation for sensing those parameters that facilitate the diagnosis of critical production facilities used in a plant or business.However the vast majority of mechanical, electrical, hydraulic, and pneumatic equipment that may be classed as critical in the operation of a plant should be subjected regularly to those diagnostic techniques that can best identify their current condition and estimate when repair, modification, or overhaul should take place to avoid crash down. These inspections and evaluations are usually performed best by internal technicians that have been trained properly.

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