Does anyone have experince with usage SPECTROIL M/C-W Oil Analysis Spectrometer in CAT SOS labs? What about it's real advantages and disadvantages in comparance with ICP?

Regards,
Marat
didicoi_2004@mail.ru

We use such instruments for KOWA not SOS. Advantages are quick and easy preparation of samples (no dilution), fast analysis time, high repeatibility, good accurancy for ppm values <900 ppm. Instruments are designed for Army/Navy and are very solid in design.

Couple of points

Advantages of Spec M
-Spec M requires no sample prep (dilution).
-has no running costs if you don't need it.
-Volatises 0-8µm particle sizes (more range than ICP)

Advantages of ICP
-Has the element Sulphur - less important these days with low sulphur diesel.

Cons of ICP
-High running costs if no samples done - constantly needs to be on, and while on consumes gas.
-can only volatilise samples between 0-4µm sizes.

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If you do less than 3000 samples a month go for Spec M definitely. Cost of each sample = electrode sharpened + electrode disc

= Rand 3.00 = < $0.30c per sample (probably cheaper if your in the US).

Only conside the ICP if you do over 3000 samples a month - it has high running costs associated with the fact it constantly uses gas even when not analysing samples. However the cost per sample is minimal.

Andrew

If I was more interested in wear metals, definitly the Spectro. Spectro has these units set up for the right range of wear metal interest (we have two of them, one for RDE and one for RFS). Running costs are definitely acceptable. Spare parts, after-sales service and upgrades have been outstanding.

If I was more interested in additive levels, or had a significant additive level concern, probably an ICP, since it is linear through many orders of magnitude, and oil additives can range from very low to very high. I have only heard of the high running costs, and we have avoided ICP due to those stories (heard one from a Cat SOS lab themselves).

Also heard a rumour, and it may be only this, a rumour, that the reason Cat set ICP as their standard so long ago, even though the particle size issue was known, was that at the time, the Spectro had no automation, which it now has.

The Spectro can do additives, but you can run into ppm disagrements with oil company labs who are usually using ICP's. When we have a sample that is being analyzed for additive interest, we make it known to the customer that there is the possibility that our additive results may differ from the oil company results or other lab results that are using an ICP.

quote:

Originally posted by Marat Turumbetov:
Does anyone have experince with usage SPECTROIL M/C-W Oil Analysis Spectrometer in CAT SOS labs? What about it's real advantages and disadvantages in comparance with ICP?

Regards,
Marat
didicoi_2004@mail.ru

ICP is absolutely the best and most accurate and reliable instrument. It spits out at once concentrations of additives, contaminants, and wear. I guess all those folks that constantly talk about particle size limitations of ICP (0-4µ, or 0-10µ, or whatever) probably never heard of acid reflux digestion (not a rocket science at all). Once an aliquot of oil sample is digested, all metals are in solution, the solution is analyzed by ICP and concentration determined, and all that talk of size limitation becomes a bunch of bull (what actually is for everyone familiar with the capacity of ICP instrument). And here we are talking about capacity of accurately analyzing dozens and dozens of different metals, like no other method, period. Of course, just like with everything else, one needs to run a baseline (new oil) in the same manner to be able to take the full advantage of the complete and accurate picture of all metal in their oil.

In a former life I worked on the particle size limitations of RDE, ICP and DCP emission spectrometers and AA spectrophotometers for the US Air Force and Navy. We also worked on acid digestion (aqua regia/without and with HF for Ti and sand)and spoiler designs(part inside spray chamber designed to remove droplets above a certain size range to stabilize plasm/flame and in doing so remove particles)to improve particle size capabilities. Published a bunch of papers with Saba and Rhine in the late 80's.
One thing that I did later on was to devise a capacitor system that allows the emission spectrometer to tell the analyst the approximate size/composition of the particles in addition to the concentration (published in Lubrication Eng.). I believe that capability is on all current ICP spectrometers possibly RDE (during sample warmup time).
If you really care if particles are present:
When setting up your flush time between samples on ICP, you monitor the output to tell when the signal returns back to zero after running a high standard/sample - to prevent carryover between badly contaminated samples. If you run your samples in that same mode you can quickly check for particles - smooth output homogeneous sample, no particles vs erratic output, hetergenous sample, particles present up to size limitation of spectrometer (usually 1- 3 microns measured quantitatively, 3-10 microns detected but only partially analyzed, emit light higher in plasma). The bigger the spikes, the bigger the particles.
Also if you run one set straight and other set with acid digestion, difference will indicate particles present.
Of course this is assuming you got a representative sample from the lubrication system and you agitated the sample adequately prior to analysis.

Bob K.,

During my employment with a couple of prominent commercial laboratories, and later at the USACE North Pacific Division Materials Lab, we mostly used hot conc. nitric acid reflux digestion, which is tremendous oxidant, and was sufficient to address clients/Corps’ requests.

Anyhow, I am not trying to be argumentative here, but I am really interested to know, how, and to what degree of certainty, you guys measured 1-3 micron particles in establishing (ICP particles limitation”), when there was not a single reliable standard known for that range of particles, until the ISO 4406 in 1999 introduced first traceable and reliable/repeatable 11171 calibration standards? Also, did you, or do you know if anyone else confirmed those “limitations" by using the traceable ISO 11171 standard levels? There are supposed to be limitations for RDE too, but I don’t see any comment to that extent. All I see is ICP technique being constantly marginalized when talking about trace metals. Could it be that there are some other reasons for downplaying ICP and favoring RDE that has nothing to do with science but everything to do with profit making?

John
We spent about 3 months preparing metal powder suspensions of every metal of interest to AF: Fe, Cu, Ag, Mg, Al, Cr, Arizona Road dust, Ni, Ti, Mo, and so on. We started with 325 mesh powders and dry sieved them to obtain 30 - 20 and below 20 microns. Then we made up suspensions of below 20 microns and passed them through Nucleopore filters (absolute pore sizes) to produce suspensions of 20-12, 12 -8, 8-3, 3-1 and below 1 microns. Used SEM/optical measurements to confirm sizes. Used acid digestion to determine concentrations. Then ran suspensions on RDE,ICP,DCP and AA versus soluble standards from Conostan. So for below 1 micron and 1-3 microns all instruments and Conostan standards of equal concentrations gave equal results, so no limitations. Above 3 microns efficiences differed and depended on numerous factors. With RDE, particle density and shape mattered since particles fell out of solution during 6 second warm-up. So for Al still detected 30% of 8 - 12 micron particles but for Cu did not detect particles above 8 micron. If we dispensed oil directly onto RDE or used rotating platform, ashed oil, then analyzed could detect up to 75 micron particles regardless of density or shape. RDE used as filters - oil drawn by vacuum through RDE - has been used on oil samples known to have particles DCP>ICP>AA for most metals - higher melting metals such as Ti and Mo, AA did alot worst. ICP detected 1-3 accurately detected atleast 20% up to 8 microns. Could increase size capabilities 2-3 fold by modifying spoiler but signal stability decreased because of larger drops.
AF/Navy liked RDE because cap of sample vial could be used as sample holder for RDE and no consumables. Also in hot,humid conditions lighting ICP torch can be troublesome to exciting (arcing). ICP strength is stability. DCP was actually much better at wear debris analysis but had to be restandardized every few samples due to thermal effects. Used Aqua/regia for most metals except used HF/HNO3 for Ag and Ti and Aqua regia/HF for road dust - used acid resistant ICP torch - ultrasonically agitated for 5 minutes then diluted with surfactant (Neodol 91-6/8) and kerosene for ICP or surfactant and MIBK (methyl isobutly ketone) for DCP and AA
Most of above published in Lub. Eng or Analytical Chemistry mid to late 80's.

Malte Lucas more or less founder of Baird Atomic had similar results focused primarily on RDE.

Thanks Bob. This was quite an interesting (and logical) endeavor. I admire people who have the knowledge and strong attitude to find answers, and are willing and able to elaborate their achievements (failures too, as they are part of the learning curve). I see your interest is, and was, in advancing practical application of science, and your outlook seems untainted by any outside influence. I wish we had crossed paths at some point in our professional careers, as I always had similar predisposition and curiosity (being devil’s advocate is just one little segment of it). Cheers!