What is the lowest part of the water side of a horizontal return tube boiler called?

The lowest part of the water side in a horizontal return tube boiler is referred to as the mud drum. This component plays a crucial role in the functioning of the boiler by providing a space for sediment and other impurities that may settle out of the water during operation. The mud drum collects these heavier particles, which ensures that they do not enter the steam generating sections of the boiler. This helps maintain water quality and prevents damage to the boiler and its components.

In a horizontal return tube boiler, water is circulated, and as it heats up, any impurities that are present tend to settle at the bottom due to gravity. The mud drum is designed to hold these impurities, making it easier for operators to periodically remove sludge and maintain the efficiency of the boiler system. By keeping the system clean, the mud drum contributes to the longevity and reliability of the boiler, which is critical in high pressure applications.