How many threads are required for 1-1/4" metallic pipe?

For 1-1/4" metallic pipe, the correct number of threads required is 11 threads per inch. This is based on industry standards for NPT (National Pipe Thread) which dictate that standard pipe threads for a pipe of this size are specified to have 11 threads per inch.

This standardization is important as it ensures compatibility between different manufacturers' products and allows for a secure and leak-free connection when fittings are utilized. The NPT thread designation centers around the pitch and size of the pipe, and for 1-1/4" pipes, it specifically calls for 11 threads.

Understanding this specification is crucial for journeymen in the mechanical and gas fields, as using the wrong number of threads can lead to inadequate sealing and potential system failures.