What is the effective thread length of a 3" diameter screwed pipe?

To determine the effective thread length of a 3" diameter screwed pipe, it’s essential to refer to standards and conventions typically used in plumbing and piping systems.

For a 3-inch pipe, the effective thread length is generally defined based on the nominal pipe size. In practice, American National Standards Institute (ANSI) guidelines indicate that the effective threads for various pipe diameters have specific standard lengths.

In this case, for a 3-inch diameter pipe, the effective thread length is quantitatively determined to be 1 1/2 inches. This standard length is critical because it ensures proper engagement of threads and maintains a secure connection between pipes and fittings.

Other options correspond to different effective thread lengths that do not align with established standards for a 3-inch diameter pipe. Therefore, the selected effective thread length of 1 1/2 inches is accurate, reflecting both standard engineering practices and ensuring compatibility and safety in pipe installations.