A Matter of Consensus and Repeatability

MolaKule

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One of our members asked this question in an earlier thread on this Forum:
Quote:
GaleHawkins: My question is about the value of Falex Seizure MolaKule and I was hoping you point out the functional value of Falex Seizure testing beyond marketing hype. I think in can start a new thread if you wish that action.
A set of standards for the testing of materials had to be created for the establishment of consumer confidence and to foster international trade. The US Military had developed a number of Performance Standards, specifications and basic tests for the procurement of Military materials and supplies, but these did not cover industry-wide materials specifications. Thus, a set of standards was developed by the ASTM and later by the CEC and JASO, to establish standard testing methods on an International basis that could be repeated in any laboratory using equivalent testing machines and methods. These standard testing methods not only cover petroleum products or lubricants, but also cover a plethora of materials testing for many industries. http://www.astm.org/HISTORY/hist_chapter1.html These tests have been developed over many decades by many labs, both in industry and academia, in order to meet the increasing needs of various industries. These testing methods are not advertising hype, but are a consensus of documented testing methods and protocols to foster repeatability and to establish some standardization of same. Most lubricant manufacturers do list their testing methods because their customers require them. For large industries with expensive machinery, a lubricant must have passed certain tests and must have shown some efficacy. For example, in a large electric generating plant, it is good to know the lubricant you have ordered in large quantities has passed certain tests in order to provide sufficient protection for machinery longevity. As requirements increased in terms of increased performance, new tests had to be developed to more closely reflect operating conditions. Here are some tests that may answer the member’s question (since the question about which test was not given): ASTM: D 1947, Standard Test Method for load-carrying capacity of petroleum oil and synthetic fluid gear lubricants. D 2670, Standard Test Method for measuring wear properties fluid lubricants (Falex Method). D 2782, Standard Test Method for measurement of extreme-pressure properties of lubricating fluids (Timken Method). D 2783, Standard Test Method for measurement of extreme-pressure properties of lubricating fluids (Four-Ball Method, Load Wear Index). D 3233, Standard Test Method for measurement of extreme-pressure properties of lubricating fluids (Falex Method, Pin and Vee Block). D 4172, Standard Test Method for measurement of wear preventive characteristics of lubricating fluids (Four-Ball Method). D 4857, Standard Test Method for determination of coefficient of friction of lubricants using the Four ball wear test machine. D 5182, Standard Test Method for evaluating the scuffing load capacity of oils (FZG machine visual method). D 6425, Standard Test Method for measuring friction and wear properties of extreme-pressure (EP) lubricating oils using the SRV testing machine. CEC: L-07-A-85, Load-carrying capacity test for transmission lubricants using the FZG rig. As you can see, there are many tests using many different types of machines. And these tests apply primarily to manual transmission and gear lubes. There are many other tests for gas engine oils, diesel oils, hydraulic fluids, etc. So the question is, which test do I use? One of the answers is, what does my customer require in terms of testing? Another answer is, which test do I consider to be the most severe for the specific application? Another answer is, which test most applies to real world operation and conditions? A comment about the various Four-Ball Tests: As you can see from the above abbreviated list, there are many Four-Ball tests. Some test for wear, some test EP characteristics, some test to determine friction coefficients, such as D 4857, Standard Test Method for determination of coefficient of friction of lubricants using the Four-ball wear test machine. Many of these tests are used by we formulators to compare various lubricant and additive combinations during the development process, and one of those is the Four-Ball wear scar test. In my opinion, this should only be used in internal testing, not publicized, and here is why using an example. I take a 30 weight mineral base oil (10.5 [email protected]) and do a wear scar test. Let’s say that by itself it shows a wear scar of 0.55 mm. I add some ZDDP of about 300 ppm. It shows a wear scar of 0.35 mm. So what’s the point? It is ONLY A RELATIVE, Comparitive test of merit. I.E., you have to compare your baseline using XX lubricant against another YY lubricant. Speaking for myself, I do not think this test should be used in advertising and in my further opinion, it only means something if you PUBLISH what the base line fluids happen to be.
 
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Originally Posted By: MolaKule
These standard testing methods not only cover petroleum products or lubricants, but also cover a plethora of materials testing for many industries. http://www.astm.org/HISTORY/hist_chapter1.html
For anyone with a spare $30, I would recommend USS Lubrication Engineer's Manual Has very little current cutting edge stuff like ACEA specs, Dexos, etc. but quirky little explainations of the standards, how they work, and what they (hoped to) achieve. hundreds of pages of stuff like ... this one on grease "penetration"
 
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