What does HTHS mean?
1 Answers
HTHS stands for "High Temperature High Shear viscosity," which is an indicator of the viscosity stability of engine oil under high temperature and high shear conditions, reflecting the oil's ability to maintain lubrication under such conditions. Here is some relevant information: Relationship between oil viscosity and anti-wear properties: From an anti-wear perspective, it's not just the oil film that plays a role, but more importantly, the additive formulation of the oil. The anti-wear additive system is crucial because wear occurs under the most extreme boundary friction conditions during operation, where the oil film between friction pairs no longer exists and cannot provide anti-wear protection. Additional chemical components, such as zinc, molybdenum, and phosphorus, are needed to provide anti-wear effects. HTHS value and the engine: When the engine reaches normal operating temperature, wear occurs under extreme boundary friction conditions. At this point, the oil film between friction pairs is extremely thin, requiring both oil film strength and anti-wear additives to provide protection. Whether during the compression stroke or the power stroke, the piston experiences the highest pressure near the top dead center. Due to the circular motion of the crankshaft, the connecting rod is mostly in an inclined position, increasing the pressure on a single side of the piston. This results in extremely high shear pressure from the piston ring against the cylinder wall. Combined with high-speed shear motion, severe boundary friction occurs. If the oil film strength is insufficient and breaks, accelerated wear is inevitable. This wear can lead to reduced sealing within the cylinder, allowing oil to enter the combustion chamber and burn. Deterioration and damage: If the tire pressure exceeds the standard by too much, it can cause excessive outward expansion of the tire, weakening its strength and reducing its lifespan. Before inflating, clean any dirt from the valve stem and ensure the valve core is not loose. After inflation, check for leaks and secure the valve cap to prevent dirt from entering the tire. Tire pressure can be measured using a tire pressure gauge. Measurements taken at room temperature are more accurate, while those taken at very high or low temperatures are less reliable.
