With the recent cost reductions in the market of vibration analyzers and the release of in-house analysts to the market, what makes a good contract analyst these days? In the Reciprocating equipment world, the selection of a good analyst is a daunting task with the different options available out there.
In short, it takes a wide array of skills to make a good analyst. Some analysts are former mechanics, which is great as you know the internals of most pieces of machinery. The short fall may be in the theoretical aspect of compression and the properties of compressing gas or vibration and forcing functions. Others may be representatives of the analyzer manufacturer, which brings many skills in the use and interpretation of the data from the instrument. Applications may not be as varied here and the sales aspect of getting the instrument sold may steer some analysts focus.
Having an analyst that can draw from the theoretical aspect, mechanical aspect and have the exposure of working with more complex issues can round out a good analyst. Being a troubleshooting analyst also takes a special aspect as you have to be part detective to try and assemble data, facts, and your own interpretation of the issues to come up with the best possible solution. This is where experience is a key factor as well as some issues are similar in fashion and the fixes found in the past may help to shape the new solution. Its not as easy as just putting in a brace to get some vibration under control, though that is most times the fix. MORE STEEL! Well, having the ability to understand the Forcing Function of the vibration source, will give you better bang for the buck. The right fix may not have anything to do with bracing at all and could be better controlled for ever, instead of just for now. Immediate fixes are cool and visual, but having the vibration problems come back a year or so down the road with conditions change, leaves a sour taste.
I’ve run into situations where bracing was just thrown at machinery in the hopes of “chasing the vibration” out of the building and there was really no supporting data other than “it worked before”. Spending some time to understand the forcing function and the dynamics of the problem makes the solution more certain and less trial and error.
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Performance problems are also more than just taking data and printing out the plots. I also see a lot of “data-first” reports supplied out there and really, what are the analysts being paid for? Does the doctor just hand you the x-rays and says “see, its a problem”? Uh, no.. It takes more to understand issues with regard to compressor performance than just getting the data in the box. Interpretation of the data and supplying analysis is the value in the service. The software is getting more advanced and more “expert systems” are being developed to try and remove the subjective approach of teaching the analyst how to interpret the data. But relying on the analyzer software has been an issue as it has removed the analyst from the decision. I still use the 3 strike rule where its like the law, 2-3 pieces of evidence makes it more likely to be true and a confident recommendation can be made.
As you can see it takes more than just and analyzer and a computer to make a good analyst. Knowing the difference between a simple problem and when to pull out the big guns is key to making timely and cost effective solutions.
Jason Hoffman at EMS Inc.
Good article. I thoroughly enjoyed it.