Select the correct term for a horizontal steam supply line.

The term "steam main" refers specifically to a horizontal steam supply line that carries steam from a boiler or steam generation point to various locations within a facility or system. The steam main is typically large in diameter to accommodate high volumes of steam and is designed to maintain pressure and temperature as the steam travels.

This distinction is vital because steam mains are integral to the distribution network of a steam heating system. They function as the main artery through which steam flows, providing energy for heating or power generation in industrial settings.

In contrast, other terms such as steam riser or steam trunk have different meanings within steam system terminology. A steam riser refers to a vertical pipe that carries steam upward from one level of a building to another. A steam trunk is typically a larger piping configuration that can transport multiple streams of steam or condensate and may include devices like separators or traps. Lastly, a steam feeder is usually associated with supplying steam to a specific piece of equipment or processing unit, rather than serving as a broad supply line. Understanding these distinctions enhances your grasp of steam system terminology and functions.