What is the specific number designation for fuel oil that needs to be heated before it can be pumped?

The specific number designation for fuel oil that requires heating before it can be pumped is Number 6. This grade of fuel oil is known as heavy fuel oil or bunker fuel and has a higher viscosity compared to lighter oils. Due to its thicker consistency, it must be heated to reduce viscosity, facilitating smooth pumping and combustion in steam boilers and other industrial applications.

In practice, Number 6 fuel oil often requires heating to temperatures of around 100 to 140 degrees Fahrenheit, which allows it to flow more freely through pumps and pipelines. Understanding the characteristics of different fuel oil grades is essential for safe and efficient operation in marine and industrial settings, where the proper handling and preparations for fuel oil are critical for maintaining equipment performance and ensuring safety.