What method is used to layout the pattern for a T branch?

The correct answer is the parallel line method, which is commonly used for laying out patterns for T branches in sheet metal fabrication. This technique involves creating a series of parallel lines that represent the sides and dimensions of the desired branch. It allows for accurate measurement and ensures that the dimensions are consistent throughout the pattern.

Using the parallel line method, the fabricator can easily visualize and measure the angles and lengths needed to create the T branch. This is essential for ensuring the proper fit and functionality of the branch when it is integrated into a duct system.

The other methods mentioned, such as the volumetric method, radial line method, and conical method, are typically used for different types of shapes and configurations. For example, the radial line method is better suited for layouts that require arcs or curves, while the conical method is used for creating transitions in round ducts. Each method has its specific applications, but the parallel line method is the most effective for T branches, ensuring clarity and precision in the layout.