Engineman (EN) A School Test 1 Practice Test

Cold-flow performance is about whether fuel oil will still move through lines and filters as the temperature drops. Wax crystals form in the oil when it gets cold, thickening it and eventually stopping flow. The pour point is the temperature at which the oil will no longer pour under standard test conditions, so it directly indicates when the fuel will cease flowing in cold weather. While viscosity affects how easily the oil flows at a given temperature, it doesn’t define the temperature at which flow stops. Flash point and density relate to ignition and mass per volume, not to low-temperature flow behavior.