What is the lowest temperature at which an oil can flow called?

The lowest temperature at which an oil can flow is referred to as the pour point. This term is crucial in the field of lubrication and fluid mechanics because it indicates the minimum temperature at which the oil remains fluid enough to be pumped or flow freely. Below this temperature, the oil may thicken or solidify, making it difficult to use in machinery or engines.

Understanding the pour point is vital for ensuring proper lubrication in various temperatures. Different oils have different pour points, which significantly impacts their performance in various operating conditions. The pour point helps in selecting the right lubricant for specific applications, especially in extreme weather conditions.

The other terms mentioned, such as thermal point, viscosity point, and flux point, do not accurately define the threshold temperature related to the flow of oil and are not standard terminology used in the industry. Hence, pour point is the appropriate and commonly used term for this concept.