Originally Posted By: Shannow
Originally Posted By: Gokhan
Originally Posted By: PimTac
So you are saying that Chevron invented the BOQI index?
They invented the idea that NOACK and CCS
together can be used to predict the base-oil quality
For anyone interested in what the Chevron patent ACTUALLY was for go back a few pages and read what I posted on reviewing it.
It’s a predictive tool for oil blending, using base oils of KNOWN quality from their slate.
Co-opting the premise to this nonsense, and then claiming that
* it’s supported by Chevrons patents; and
* to deny that BOQI works and is valid is to claim that Chevron’s patents are false.
Is in the first point laughable, and the second a ridiculous straw man attack.
Shannow, I think people on BITOG have long been familiar with that it's typical of you to you use words such as "
nonsense," "
ridiculous," "
straw man," and "
wow" in order to
shoot down others' ideas and statements.
No, you never understood the Chevron patent. Instead, you made the
blatantly false claim that the entire dozens-of-pages-long patent was about nothing but the SAE cold-viscosity requirements (5W, 10W, 15W, etc.). If there is something ridiculous, then nothing is more ridiculous than your analysis of the patent that reduces it to a trivial claim.
Why in the world do you even need a patent or a complicated method to determine if a base oil meets the cold-spec requirements? CCS, MRV, NOACK, KV40, KV100, VI, and NOACK values are already measured and tabulated for the base oils they have. These quantities are entirely sufficient for determining if the base oil meets the viscosity and NOACK requirements of a given SAE/API spec.
Chevron patent: Method for predicting a property of a base oil (link)
The patent goes into great detail in discussing base-oil quality for various base-stock types.
Some of the key claims are that
(1)(c)... wherein the curve predicts whether a base oil that is a blend of the first base stock and the second base stock will meet base oil requirements for a finished lubricant;
(4)... wherein the multigrade engine oil meets an engine oil specification selected from the group of API CJ-4, ACEA E9, or a combination thereof.
The patent is really long and difficult to analyze and digest. However, by requirement, they are talking about an empirically established target CCS and NOACK range, not simply the SAE/API maximums.
It's really complicated and they make a great effort toward understanding the base-oil quality for practical oil-blending applications.
Now, this is the interesting part regarding the base-oil quality index (BOQI)!
After a very lengthy and complicated analysis, they define this quantity:
(0036) In one embodiment, the base oil has a
ratio of NOACK volatility to CCS VIS at -25° C multiplied by 100 within a desired range. The desired range may be from 0.80 to 1.55, from 0.90 to 1.40, from 0.90 to 1.30, or from 1.0 to 1.30.
This is their (unsuccessful) attempt at BOQI!
They then give examples in (0064):
"
Chevron's BOQI" = 100*NOACK/CCS@-25 (lower the better)
Oil A: 1.19 = 1.00 * Oil A (0% better)
Oil B: 1.06 = 0.89 * Oil A (11% better)
Oil C: 1.88 = 1.58 * Oil A (58% worse)
Let's compare this with "
my 1/BOQI" = NOACK*CCS@-25/1,300,000 (lower the better)
Oil A: 0.0170 = 1.00 * Oil A (0% better)
Oil B: 0.0162 = 0.95 * Oil A (5% better)
Oil C: 0.0220 = 1.29 * Oil A (29% worse)
While the Chevron BOQI and my BOQI are in the same direction, look at them and decide which one makes more sense? Their BOQI values are highly exaggerated if not unreliable because they failed to correct for CCS! In other words, they did make an attempt at BOQI but it wasn't very succesfful, as they missed the opportunity to correct for the CCS and obtain a better benchmark.
There is another example in (0067):
"
Chevron's BOQI" = 100*NOACK/CCS@-25 (lower the better)
Oil A: 1.76 = 1.00 * Oil A (0% better)
Oil B: 3.22 = 1.83 * Oil A (83% worse)
Let's compare this with "
my 1/BOQI" = NOACK*CCS@-25/1,300,000 (lower the better)
Oil A: 0.0031 = 1.00 * Oil A (0% better)
Oil B: 0.0039 = 1.26 * Oil A (26% worse)
Obviously 83% worse doesn't make sense because Chevron fails to correct for CCS and my BOQI gives a much better prediction for the base-oil quality and/or performance.
In summary, the Chevron patent is very long and complicated and they make an honest and rigorous attempt in dealing with the base-oil quality and/or performance
by solely studying the NOACK and CCS behavior. They do introduce an "index" in the process but they fail to observe that the index can be made more robust by simply accounting for the effect of CCS on NOACK, while still considering the effect of both NOACK and CCS on base-oil performance. My base-oil quality index (BOQI) improves on Chevron's index by accounting for CCS variations and making it a more
universal property, which can be very useful in comparing base oils and also correlating them with API base-stock groups.