What is the primary purpose of using a Test Mandrel?

The primary purpose of using a Test Mandrel is to assess the internal condition of the duct, particularly to ensure that it is clear of obstructions. When a Test Mandrel is inserted into the duct, it can help verify that the duct is not only the right size but also free from blockages or constrictions that could affect airflow and system performance. This is crucial in maintaining the efficiency of HVAC systems or other ducted ventilation systems, where any obstruction could lead to reduced airflow, increased energy consumption, or system failure.

In the context of ductwork, while measuring size, testing strength, or securing connections are important aspects of duct installation and maintenance, they do not specifically align with the primary function of a Test Mandrel, which is focused on identifying obstructions within the duct.