What is the effective number of threads of a 1/8" diameter screwed steel pipe?

The effective number of threads for a 1/8" diameter screwed steel pipe is derived from standards that specify the number of threads per inch for pipe threads. For a nominal pipe size of 1/8 inch, the American National Standards Institute (ANSI) specifies that there are 27 threads per inch (TPI) for this size of pipe. The threading on steel pipe is critical in terms of ensuring a secure and leak-free connection, and this standardized threading makes it vital for engineers and construction professionals to adhere to these guidelines for proper fittings and assemblies.

The given options present various common TPI values, but only the value of 27 is officially recognized for 1/8" diameter pipes. Understanding the specifications helps to avoid issues with fitting compatibility and potential leaks in plumbing and industrial applications.