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[Video] Your Lab Reports Are Probably Wrong -- Here's How To Save Them

Tue, Aug. 16, 2016

When looking at a lab report, it is assumed the information on the report is accurate. A certified lab will not usually make an error in the report, but if so, it is obvious and easily fixed. Ever hear the saying "By the time the lab gets the report the error has already been made"? For the most part, this is true. Where people are led off course is believing the particle count on the lab report is the gospel. This is natural, but unfortunately not always the case with a bottle sample unless you already employ the techniques listed in the video below.

How does the sample get contaminated?

Anytime a lubricant is removed from the system, sample contamination before reaching the lab is inevitable. Some examples of this happening include:
  1. When a sample valve is closed, a pseudo wall is formed from contamination in the oil to fill the void. This is normal. If the valve is not cycled and flush volume is inadequate, as the sample is collected, contamination is picked up as oil flows through the valve.
  2. If a sample hose is used, contamination present in the hose is picked up.
  3. As oil interacts with the air while being transferred to the sample bottle, contamination is picked up.
  4. Contamination inside the new bottle is collected by the oil.
  5. Lastly, the one source of contamination most people forget...the sample bottle lid. The lid also holds contamination that will be picked up by the oil.
With all these variables entering into the equation, how in the world are we to expect to have accurate information on the lab report? Well, we are not. We cannot look at the particle count on a lab report and assume it is perfect.

What we can do is dial in our sampling practice enough to eliminate as many variables as possible so that we can use the particle count information on the lab report for accurate trend analysis.
The following video demonstrates how to properly collect a bottle sample to ensure trend analysis accuracy.





Video Transcript

Hi, my name is Scott Howard with Hy-Pro Filtration and today we will talk about sampling best practices.

We have a sample port here that’s located upstream of the pressure filter. The reason it’s upstream is you want to analyze the reservoir barrel or tote contamination levels to determine if you are under your limit for either your system or to add new or used oil to your system for use.

Upstream gives us information on the entire reservoir, you can then test downstream for filter element performance or to determine if there’s bypass in the housing. But for trend analysis, upstream is preferred.

What we will do here is show how to acquire a proper bottle sample. When we open the valve you want to agitate the valve vigorously several times to get low inside that valve to knock the contaminate that has built up in the valve out of the valve and out of the tubing and into the bucket, prior to pulling a bottle sample.

Usually you need an assistant or a third hand to help in the process. If there is no assistant available, what we use is, we’ll drill a hole into the top of the bucket that is just a little bit smaller than the tube you will use. Then we’ll stick the tube into the top of the bucket, face it down, but not straight down so the bottle is not under the tube for potential fallout contamination. We want it at an angle.

Again, when you start filling your bottle, after you have agitated your valve, you create a certain amount of flow rate that is easy to pull a bottle sample but enough flow to continue with flushing. Once you start flow, you do not stop flow until you’re complete with filling your bottle.

We will fill the bottle four times. The first three times, we will fill ¼ to ⅓ full, recap the bottle, agitate vigorously and dump into the bucket. We recap the bottle because the cap itself has contamination.

There are four components that must be flushed to acquire a good bottle sample or a solid contaminant trend analysis: your hose, your valve, bottle, your cap. All four must be flushed. Do not purse the gap in your lips while you’re pulling the sample. Breathing on the cap can add up to 200ppm of water to your lab results.

Here is the process.

First we will agitate the valve. Then create an acceptable flow rate that’s not too fast to splash but enough to continue flushing the line.

Then we will fill the first three times, ¼ to ⅓. Flush the bottle and the cap, continuing to allow the valve and the hose to continue flushing. By the fourth time we will expect all four components to be clean so our trend analysis on the lab report from this bottle sample will be believable. Okay? So here we go.

¼ to ⅓. Agitate vigorously. When you dump the oil back into the bucket, make sure not to splash so there’s no contamination potential.

Third time, same thing. Recap. Agitate. Dump.

The fourth time you fill it up to the neck.

At this point in time, then cap for the last time, and then shut off flow.

Now you know you have a good sample because the hose, the valve, the bottle and the cap have been flushed. You have flushed them three times, and then filled it. Fill it more than 75% of the bottle but not completely full. You do want an air pocket so that when the lab receives it or if you do this in-house, you can agitate the contamination that has settled to the bottom.

Make sure that when you run the test through the laser counter, the particle count is representative of the entire bottle. Then, you can have good, believable trend data for solid particle contamination. Thank you, this is Hy-Pro Filtration.


Need help translating your fluid analysis reports into actionable information? Download our Fluid Analysis Reference Guide below!

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Written by Scott Howard


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