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In This Issue:

• Up Front: All Top-up Containers Are Not Created Equal

• Book Bits: Synthetic Oil Solves Turbocharger Problem

• Today's Tip: In a Jam? - Try This Quick Test

• Q & A: Don't Throw Out the Evidence - Seize It!
  

Up Front

All Top-up Containers Are Not Created Equal

An operator conducting routine rounds noted a slightly low oil level on the journal bearing housing of a large electric motor in continuous service. The well-intentioned operator proceeded to use a top-up container on hand, labeled as the appropriate product, to return the oil level to the correct level.

On a subsequent round, the operator noticed fumes, as well as a loud rumbling noise that appeared to be generated by that same bearing housing. Based on that visual inspection, supported by increasing vibration levels reported by the continuous monitoring equipment, the fan was removed from service. Unfortunately, upon closer inspection, it was determined that severe damage had already occurred; the motor required a major overhaul.

Analysis of the remaining oil in the top-up container used to refill the bearing housing indicated moisture levels approaching 50 percent. Severe moisture contamination introduced during top-up no doubt prevented the formation of an effective lubricating film, and therefore resulted in massive and rapid bearing damage from metal to metal contact.

Since this event, we have replaced all of the top-up containers at our facility with sealable plastic types to prevent large- scale moisture contamination. We consider this expense to be inexpensive insurance against future failures of this type.

(Submitted by Noyan Ercan, Reliability Engineer, Shell Refining Australia. Thanks Noyan!)

Each Up Front story published will earn the sender $50. To submit a case study, experience or lesson learned click here or e-mail info@noria.com. Let us hear from you.

Book Bits

Synthetic Oil Solves Turbocharger Problem

From "The Practical Handbook of Machinery Lubrication":

A construction equipment contractor was experiencing premature turbocharger failures when certain engines were operated under full load conditions and used around the clock. Investigation through oil analysis and diagnosis of the failed components, revealed that the failures were caused by coking of the petroleum base oil within the turbocharger oil passages, thus restricting oil flow and resulting in bearing failure.

The initial cause of the oil coking condition was excessive temperatures within the turbocharger housing. A fully synthetic diesel engine oil was selected of the same viscosity as the original petroleum base mineral oil and installed. Premature turbocharger failures did not reoccur and oil temperatures dropped by about eight degrees Fahrenheit.

Click here for more information about "The Practical Handbook of Machinery Lubrication".

Today's Tip

• Suppose you run out of a lubricant, and are in critical need to top-off the reservoir. If the equipment is force-lubricated from a sump, it is usually better to leave it a little low until you can get the proper fluid. If you simply cannot resist the temptation of conducting a science experiment - and are ready to grab a pail of Brand X to pour on top of Brand Y - first take a few minutes to perform this simple test:

  • In a clean clear plastic bottle, add equal amounts of both lubricants, leaving some headspace.

  • Shake the bottle vigorously and allow to settle. Do you see more than one layer? A hazy or milky appearance? Any color change? Sediment? Any of these results is a red flag - a big warning NOT to mix these fluids.

  • In two separate bottles, vigorously shake samples of the two fluids separately. Do the bubbles rise to the top and pop as quickly in the mixture as they do in the individual fluids?

  If you skip the test and go ahead and mix the lubricants, a foaming problem and subsequent major disaster could be heading your way. (Tip submitted by Daryl Beatty, Project Leader, Dow Chemical Thanks Daryl!)

Each tip published will earn the sender $25. Click here to submit your tip.

Q & A

Don't Throw Out the Evidence - Seize It!

"Recently I've read that it's possible to analyze used oil filters for troubleshooting. Do you recommend this?"

Used oil filter analysis may provide your best evidence of machine degradation, tracing a history of machine particles created and contaminants ingested over a period of time.

Filters are often discarded when changed, or not analyzed as a part of a root cause failure investigation. This disregards a potentially powerful analysis tool. Ask your used oil analysis lab to perform a filter analysis for you. The filter is sectioned and the particles contained within are liberated into a solvent with mechanical and/or ultrasonic agitation for analysis. Typical tests include ferrography and elemental analysis.

This could unlock the key to your equipment reliability problems.

Adam Davis, Technical Consultant, Noria Corporation