Which of the following is a valid take-off measurement for a 90° butt weld ell for a 6" pipe?

In the context of pipefitting, a take-off measurement refers to the length that will be utilized when assessing the required length of pipe or fitting needed for installation. For a 90° butt weld ell, it's essential to understand that this fitting essentially acts as a turn in the piping system, allowing for a redirection of the flow at an angle.

When calculating the take-off for a 90° butt weld ell, the measurement typically corresponds to the nominal size of the pipe, in this case, 6 inches. This is because the take-off measurement for these types of fittings generally aligns with the diameter of the pipe being used. As a result, a 6" pipe will have a valid take-off measurement of 6 inches for the 90° ell.

This principle is critical as it influences the overall layout and dimensions of the piping system, ensuring proper flow rates and reduced losses in the system by maintaining consistent measurements that accommodate the fittings and connections being used.