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Message: You seem to be making a few assumptions that are not correct
Changed By: grant
Change Date: December 07, 2013 12:56PM
You seem to be making a few assumptions that are not correct
Change Date: December 07, 2013 12:56PM
You seem to be making a few assumptions that are not correct
1. you state: [i]"So, POA oil have all the characteristics one is seeking in an oil and it has this without the need of additives."[/i]
[u][b]not always true[/b][/u]. Most 10w40 and 0w40 oils from the same brand and line have a similar base stock type. But - in general - 0w40 is too wide a range to achieve even with GIV stocks. By rather selecting 10w40, we select a narrower range, which reduces the need for viscosity enhancing additives. See more below. This is critical to understand. It is this range that is the problem - divide the cSt at 100 deg by cSt at 0 deg and minimize within your real needs.
Marc, you seem to be missing that I am talking straight from the formulation labs. Its a fact.
2. you state: [i]"When one seeks out an oil that has a higher W number he is seeking out an oil that has had its good flow properties at low temperatures modified with VII's".[/i] [b][u]No[/u][/b]. VIIs are used to raise the hot viscosity number. In general you select a base stock that flows st the lower end. if the range is sufficiently narrow, no additive is required. If the range is too wide, VIIs are required to raise the upper (hot) cSt. You do understand what VIIs do, right? They are temperature dependent chains that unravel at higher temperatures such that they DO NOT AFFECT low temperature flow, but extend the hot cSt. The problem is that they break down (shear) and that means a) they no longer provide hgih cSt extension, AND they contribute to sludge.
repeat, no one wants to artificially raise the lower cSt number. VIIs are not suited to the task and, moreover, this would be a step backwards. The ideal oil is 0w1000000. Sadly it does not exist, and VII fueled efforts to achieve something similar are unstable. Look at the test results.
The problem with 0w40 ( and its only a problem under high rpm and temperature, and no, there is not one magic knee in the curve) is the wide viscosity range which cannot be achieved even with GIV bases. We KNOW 0w40 shears down. We KNOW 0w40 only marginally achieves ACEA A3/B4 HTHS. We have ample evidence that it is compromised by VIIs of some type.
And i can tell you that for other large formulators, this is a known challenge - no testing required.
It seems that you have the application of VIIs backwards. No one wants an oil to flow more poorly when cold. They only want to preserve that flow, while retaining film strength when HOT. This is only possible without additives to a point. And even if you DO achieve it without additives, you have the other 0w40 problem - very marginal test results when hot, even before shear occurs.
So now i [sorta] know why you made your statement. But i hope you see that the assumption was in fact backwards, at least w/r/t common additive properties and usage.
In fact, a more ideal oil would be say 15w40 (< 3:1), 10w30 (3:1) or, say, SAE30 (1:1) - but only if those ranges meet your needs. It would place significant demands on the user, which is why compromised multi-vis oils have been developed.
Grant
[u][b]not always true[/b][/u]. Most 10w40 and 0w40 oils from the same brand and line have a similar base stock type. But - in general - 0w40 is too wide a range to achieve even with GIV stocks. By rather selecting 10w40, we select a narrower range, which reduces the need for viscosity enhancing additives. See more below. This is critical to understand. It is this range that is the problem - divide the cSt at 100 deg by cSt at 0 deg and minimize within your real needs.
Marc, you seem to be missing that I am talking straight from the formulation labs. Its a fact.
2. you state: [i]"When one seeks out an oil that has a higher W number he is seeking out an oil that has had its good flow properties at low temperatures modified with VII's".[/i] [b][u]No[/u][/b]. VIIs are used to raise the hot viscosity number. In general you select a base stock that flows st the lower end. if the range is sufficiently narrow, no additive is required. If the range is too wide, VIIs are required to raise the upper (hot) cSt. You do understand what VIIs do, right? They are temperature dependent chains that unravel at higher temperatures such that they DO NOT AFFECT low temperature flow, but extend the hot cSt. The problem is that they break down (shear) and that means a) they no longer provide hgih cSt extension, AND they contribute to sludge.
repeat, no one wants to artificially raise the lower cSt number. VIIs are not suited to the task and, moreover, this would be a step backwards. The ideal oil is 0w1000000. Sadly it does not exist, and VII fueled efforts to achieve something similar are unstable. Look at the test results.
The problem with 0w40 ( and its only a problem under high rpm and temperature, and no, there is not one magic knee in the curve) is the wide viscosity range which cannot be achieved even with GIV bases. We KNOW 0w40 shears down. We KNOW 0w40 only marginally achieves ACEA A3/B4 HTHS. We have ample evidence that it is compromised by VIIs of some type.
And i can tell you that for other large formulators, this is a known challenge - no testing required.
It seems that you have the application of VIIs backwards. No one wants an oil to flow more poorly when cold. They only want to preserve that flow, while retaining film strength when HOT. This is only possible without additives to a point. And even if you DO achieve it without additives, you have the other 0w40 problem - very marginal test results when hot, even before shear occurs.
So now i [sorta] know why you made your statement. But i hope you see that the assumption was in fact backwards, at least w/r/t common additive properties and usage.
In fact, a more ideal oil would be say 15w40 (< 3:1), 10w30 (3:1) or, say, SAE30 (1:1) - but only if those ranges meet your needs. It would place significant demands on the user, which is why compromised multi-vis oils have been developed.
Grant
Original Message
Author: grantDate: December 07, 2013 12:52PM
You seem to be making a few assumptions that are not correct
1. you state: [i]"So, POA oil have all the characteristics one is seeking in an oil and it has this without the need of additives."[/i]
[u][b]not always true[/b][/u]. Most 10w40 and 0w40 oils from the same brand and line have a similar base stock type. But - in general - 0w40 is too wide a range to achieve even with GIV stocks. By rather selecting 10w40, we select a narrower range, which reduces the need for viscosity enhancing additives. See more below. This is critical to understand. It is this range that is the problem - divide the cSt at 100 deg by cSt at 0 deg and minimize within your real needs.
Marc, you seem to be missing that I am talking straight from the formulation labs. Its a fact.
2. you state: [i]"When one seeks out an oil that has a higher W number he is seeking out an oil that has had its good flow properties at low temperatures modified with VII's".[/i] [b][u]No[/u][/b]. VIIs are used to raise the hot viscosity number. In general you select a base stock that flows st the lower end. if the range is sufficiently narrow, no additive is required. If the range is too wide, VIIs are required to raise the upper (hot) cSt. You do understand what VIIs do, right? They are temperature dependent chains that unravel at higher temperatures such that they DO NOT AFFECT low temperature flow, but extend the hot cSt. The problem is that they break down (shear) and that means a) they no longer provide hgih cSt extension, AND they contribute to sludge.
repeat, no one wants to artificially raise the lower cSt number. VIIs are not suited to the task and, moreover, this would be a step backwards. The ideal oil is 0w1000000. Sadly it does not exist, and VII fueled efforts to achieve something similar are unstable. Look at the test results.
The problem with 0w40 ( and its only a problem under high rpm and temperature, and no, there is not one magic knee in the curve) is the wide viscosity range which cannot be achieved even with GIV bases. We KNOW 0w40 shears down. We KNOW 0w40 only marginally achieves ACEA A3/B4 HTHS. We have ample evidence that it is compromised by VIIs of some type.
And i can tell you that for other large formulators, this is a known challenge - no testing required.
It seems that you have the application of VIIs backwards. No one wants an oil to flow more poorly when cold. They only want to preserve that flow, while retaining film strength when HOT. This is only possible without additives to a point. And even if you DO achieve it without additives, you have the other 0w40 problem - very marginal test results when hot, even before shear occurs.
So now i [sorta] know why you made your statement. But i hope you see that the assumption was in fact backwards, at least w/r/t common additive properties and usage.
[u][b]not always true[/b][/u]. Most 10w40 and 0w40 oils from the same brand and line have a similar base stock type. But - in general - 0w40 is too wide a range to achieve even with GIV stocks. By rather selecting 10w40, we select a narrower range, which reduces the need for viscosity enhancing additives. See more below. This is critical to understand. It is this range that is the problem - divide the cSt at 100 deg by cSt at 0 deg and minimize within your real needs.
Marc, you seem to be missing that I am talking straight from the formulation labs. Its a fact.
2. you state: [i]"When one seeks out an oil that has a higher W number he is seeking out an oil that has had its good flow properties at low temperatures modified with VII's".[/i] [b][u]No[/u][/b]. VIIs are used to raise the hot viscosity number. In general you select a base stock that flows st the lower end. if the range is sufficiently narrow, no additive is required. If the range is too wide, VIIs are required to raise the upper (hot) cSt. You do understand what VIIs do, right? They are temperature dependent chains that unravel at higher temperatures such that they DO NOT AFFECT low temperature flow, but extend the hot cSt. The problem is that they break down (shear) and that means a) they no longer provide hgih cSt extension, AND they contribute to sludge.
repeat, no one wants to artificially raise the lower cSt number. VIIs are not suited to the task and, moreover, this would be a step backwards. The ideal oil is 0w1000000. Sadly it does not exist, and VII fueled efforts to achieve something similar are unstable. Look at the test results.
The problem with 0w40 ( and its only a problem under high rpm and temperature, and no, there is not one magic knee in the curve) is the wide viscosity range which cannot be achieved even with GIV bases. We KNOW 0w40 shears down. We KNOW 0w40 only marginally achieves ACEA A3/B4 HTHS. We have ample evidence that it is compromised by VIIs of some type.
And i can tell you that for other large formulators, this is a known challenge - no testing required.
It seems that you have the application of VIIs backwards. No one wants an oil to flow more poorly when cold. They only want to preserve that flow, while retaining film strength when HOT. This is only possible without additives to a point. And even if you DO achieve it without additives, you have the other 0w40 problem - very marginal test results when hot, even before shear occurs.
So now i [sorta] know why you made your statement. But i hope you see that the assumption was in fact backwards, at least w/r/t common additive properties and usage.