Read Between the Lines
Our goal as Analysts at Augury is to provide you with the most specific and accurate information possible regarding the health of your machines. At times we can be incredibly specific with a diagnostic overview that sounds something like this:
“Advanced outer race bearing defects have been identified on the non-driving end of the motor. We recommend scheduling repairs during an upcoming downtime opportunity”.
The reason the diagnostic can be so specific is because the digital twin of the EP location is accurate and complete and the symptoms in the data are clear. The analyst either knows exactly which bearing part number is installed at the location, which has allowed them to reference the bearing defect frequencies for that bearing, and/or the symptoms are so clear there is nothing else that could be generating them. In these circumstances, you probably don’t need to waste any time performing other tasks or checks, unless of course, it is to identify or correct a root cause.
Often the information we have to work with is not so clear. It may be that it is a complicated machine with several intermediate shafts or gearboxes and none of them are identified differently in the Augury platform or there is no schematic to reference. It may be that there are unmonitored components downstream that generate vibration frequencies that mimic problematic issues, such as a knife downstream of a monitored servo motor which impacts at a high frequency. Or it may be that the symptoms have two distinct possible sources such as imbalance or structural looseness.
In unclear cases, we attempt to provide what information we have and our best hypothesis but it can result in a vague diagnostic result. Something like this:
“High frequency, regular impacting is occurring on point 7. We recommend slow-turning the shaft during a downtime opportunity to locate the source. If you are able to provide us with a schematic and the bearing part numbers it will aid in our analysis”.
The second to last thing we want to do is give a recommendation that results in a maintenance team being mobilized only to discover there is nothing wrong with the machine or that the symptoms we were concerned about are a normal function of the machine. However, the very last thing we want is a machine to fail when we could’ve prevented it, so we will often change the health status, sending the customer a vague alert when we believe the risk of failure is high. Thankfully, by collecting and trending 24/7 data we are able to distinguish normal from abnormal which greatly aids in the severity assessment even when the fault is not crystal clear.
As a best practice, we train Vibration Analysts who are working with added levels of uncertainty to indicate what additional information would make the analysis clear and to recommend less invasive or labor-intensive actions first. For example, if a pump is showing symptoms that may indicate structural looseness, misalignment, or imbalance, we will typically recommend you inspect the coupling, verify the alignment, and examine the structure for loose bolts or cracked welds before we recommend you open up the pump housing to check for buildup, foreign material, or wear to the impeller. You can take a similar approach when performing maintenance tasks.
Providing remote analysis is a challenging task. You never have all the information you would like and at times one piece of information could make a drastic difference. We strive to communicate what is certain and what is unclear. By “reading between the lines” of our diagnostic result, you can approach maintenance tasks in a logical manner and provide us with additional context to serve you better in the future.