How does a strainer function within a feedwater system?

A strainer plays a crucial role in a feedwater system by filtering out debris to protect downstream equipment. In any system where water is being fed into a boiler or other equipment, it is essential to ensure that the water is clean and free from contaminants and particulates that could cause damage. The strainer typically consists of a mesh or perforated material designed to capture larger particles, sand, rust, and other debris that may be present in the water supply.

By filtering out these unwanted materials, the strainer helps to maintain the integrity and reliability of pumps, valves, and other components that rely on clean feedwater. This action not only enhances the operational efficiency of the system but also extends the lifespan of the equipment by reducing wear and tear caused by abrasive materials.

In contrast, the other options describe functions that are not associated with a strainer. Heating water, regulating pressure, and measuring flow rate are all critical functions in a feedwater system but are the responsibilities of different components. Thus, option B clearly outlines the primary function of a strainer within the feedwater system.