In terms of duct work, what is a common use for a wire brush mandrel?

A wire brush mandrel is commonly used to clean the interior of ducts. This tool is specifically designed to remove dirt, debris, and buildup from the surfaces inside the ductwork. By utilizing a wire brush, technicians can ensure that the airflow is unobstructed and that the duct system operates efficiently. Regular cleaning helps to maintain air quality and system performance, which is crucial in HVAC applications.

In the context of the other options, measuring duct walls is typically done using calipers or measuring tapes, while reconnecting sections of a duct requires fittings or connectors instead of a wire brush. Smoothing rough edges might involve using tools suited for cutting or finishing edges rather than a brush designed for cleaning.