When pipe and fitting sizes are indicated as 3" x 4" x 2", what does the '2' represent?

In the indication of pipe and fitting sizes as 3" x 4" x 2", the '2' specifically represents the size of the branch line. This notation typically describes a pipe fitting where the first two dimensions (3" and 4") refer to the sizes of the main lines or the larger connections, while the last dimension (2") designates the size of the branch line that connects to the fitting.

In mechanical systems, understanding the dimensions of each component is crucial for ensuring that the system operates effectively. The size of the branch line is important for determining flow rates and overall system efficiency, making it essential to ensure that all components are compatible in size. Thus, in this context, the '2' correctly refers to the branch line, confirming the integrity and functionality of the plumbing or piping system.