![]() To find out what motor oil grade is right to keep your engine running as designed, check your vehicle manufacturer’s recommendations or simply Find Your Jiffy Lube ®. Most vehicle manufacturers specify multi-grade oils, though, both because they envision operation in a wide climate range and because efficient, emissions-controlled engines run at high internal temperatures. A liquid with a high viscosity would mean it flowed slowly. So your motor oil is always maintaining a delicate balance: it needs to flow well when the engine is cold but also retain enough body at higher temperatures to keep metal parts lubricated and separated.Įngines that operate in a narrow range (in lawnmowers or the like) may be just fine with a single-grade oil, such as a 30W. Viscosity is a property of liquids, showing that liquids resistance to flow. Too thin, and metal parts may contact and wear. Oil thins with heat, of course, but if it thins too much it won’t be able to lubricate properly, which it does by keeping parts separated by a thin film of oil. High viscosities work better when it’s hot. Since motor oil is vital to lubricating your engine, it needs to get on the job quickly, and low viscosity helps it do just that when it’s cold. When you start a cold engine, motor oil needs to travel to the top of the engine before it circulates back down. Oil naturally “thickens” with cold, but a low viscosity, thinner motor oil flows more easily and moves quickly. ![]() Low viscosities are good for cold temperatures. For example, a 10W-30 motor oil means the viscosity is at 10W when the engine is cold and 30 when the engine is hot. How can we tell the difference between high viscosity and low viscosity liquids A material’s viscosity is a measure of its resistance to flow. So what do the numbers mean? The number preceding the W designates the viscosity at a low temperature, and the number following represents viscosity when the engine is hot. Apple juice has low viscosity, cold honey has high viscosity. The more viscous, the slower it will move. Imagine pouring motor oil out of the bottle how fast it comes out indicates the viscosity. Viscosity measures how much the motor oil can resist flow. All rights reserved.You hear the word all the time when you are getting your oil changed, but exactly what is viscosity? It’s what the numbers and letters stand for on motor oil bottles - 10W-30 for example. It’s logical to assume that a low viscosity oil is. High viscosity oils flow more slowly and come with a higher SAE number. The quicker an oil flows, the lower its viscosity and the grade assigned to it by the Society of Automotive Engineers (SAE). The term high viscosity should not be used as a descriptor of cement that reaches dough phase more quickly, but rather cement that has a higher viscosity at its dough phase when it is typically applied.Īseptic loosening biomaterials cement penetration cement viscosity radiolucent lines total knee arthroplasty.Ĭopyright © 2021 Elsevier Inc. In the simplest terms, viscosity refers to how well a lubricant flows at a given temperature. These findings suggest that the marketing description of HVC or LVC is not necessarily a factor in cement penetration. There were fewer tibial radiolucencies with HVC than LVC. There was no significant difference in maximum penetration in any zone between the two cements. Mean maximum cement penetration in 3 of the 4 zones was >3 mm with both cements. There were no cases of aseptic loosening in either cohort at a mean of 29 months. However, the vast majority of lubricants on the market will have VIs in the range of 90 to 160. Other lubricants can have VIs ranging over 400. Depth of cement penetration and presence of RLL were measured in four tibial zones and were compared between cohorts. Lubricants with VIs as low as minus 60 are available today. The HVC (n = 50) and LVC cohorts (n = 50) were gathered from two sequential series of primary total knee arthroplasties using the same implants and cementing techniques. We hypothesized that no significant difference would be found in depth of penetration or presence of RLLs between the two cohorts. We compared cement marketed as high-viscosity cement (HVC) with one marketed by the same manufacturer as low-viscosity cement (LVC). Previous studies have shown that the depth of cement penetration and the presence of radiolucent lines (RLLs) correspond with the risk of aseptic loosening in total knee arthroplasty, while others have found a correlation between the viscosity of the cement and the depth of cement penetration.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |