Perchlorate by EPA SW 846 Method 6850

To save money! Machinery is expensive. Research has shown that repairing a failed component will, on average, cost you 50% more than if the component was attended to before failure. And this does not take into account production lost during unplanned downtime.

MPE, also commonly known as Analytical Ferrography, is an extra tool in the maintenance engineer’s toolbox. It can help detect faults before wear becomes too significant. It will help you decide whether an overhaul is actually needed, and whether it needs to be done now or later. It can also tell you which part of the component needs attention when you open it up.

The skilled analyst performs the analytical ferrography to provide a root cause for wear mechanisms based on the morphology and composition of the particles, as well as which equipment component the wear particles originated from. The analyst will report material composition and wear morphology that will include, but is not limited to the following:

• Ferrous wear particles
  • High alloy steel
  • Low alloy steel
  • Dark metallic oxides and cast iron
  • Red oxides (rust)
• White nonferrous metal particles
• Yellow metals wear particles
• Contaminants, dirt (silica), fibers and other particulates
• Fatigue Wear
• Sliding Wear
• Cutting Wear—Abrasive Wear
• Adhesive Wear
• Corrosive Wear

The spectrometric analysis for a component could be abnormal, yet there is no apparent cause of the wear such as dirt or water. The diagnostician may feel that the diagnosis would be enhanced by a MPE analysis, and would recommend one. This is particularly important in a situation where dismantling may be an option. The MPE analysis could reveal that an overhaul may be premature - perhaps the machine was wearing ‘more’ (i.e. normally but at a faster rate) as opposed to ‘abnormally’—it may have been working in muddy conditions at full load, but essentially nothing was wrong.

Some maintenance engineers also like to perform a MPE at regular intervals such as at a major service. As well as providing peace of mind, these MPE’s back up and complement regular oil analysis.

Any component can have a MPE analysis performed on it. MPE is especially suited to gear and/or roller bearing systems. Drive train components such as differentials, final drive hubs and gearboxes—both automotive and industrial—are most commonly analyzed.

MPE is an additional test carried out on request to complement standard oil analysis. Conventional spectrometric oil analysis measures the concentration of an element, say iron, in a sample of oil. It is from the concentration of iron, not the actual particles that the statement of wear is produced. Whilst spectrometric oil analysis is obviously very useful, there are two limitations:

• The size of particle that is picked up by the spectrometer is limited to a maximum of 8 to 10 microns (micrometres).
• The spectrometer gives no indication of the morphology, or form, of the wear particles.

In a normal situation, wear particles are small in size (less than 8 microns). These are detected by the spectrometer. But in some abnormal wear modes, only large particles are generated which the spectrometer cannot detect. ALS is often asked why urgent action is recommended, when in fact the readings have dropped. The first limitation of Spectrometry is somewhat offset by the other tests performed, such as PQ Index. But there is no way of ascertaining the form of the wear particles without performing a MPE. So an MPE combined with spectrometric oil analysis or PQ Index gives a clearer picture of the state of your component.

Yes. In addition to ascertaining the wear mode of the component, MPE can detect other features too:

• Discoloration of the particles that indicates overheating.
• Corrosion (rust) particles are obvious.
• Black oxides indicating that lubrication is insufficient.

ALS will as far as possible strive to provide courier services for clients. Please contact the laboratory for additional information.