How many threads per inch does a 3/8" pipe have?

The correct number of threads per inch for a 3/8" pipe is 18, which aligns with the standard for National Pipe Thread (NPT) specifications. NPT specifies that a 3/8" pipe, which is commonly used in residential and commercial plumbing, has a thread count of 18 threads per inch. This measurement is essential for ensuring proper connection and sealing between pipes and fittings, preventing leaks and ensuring the integrity of the plumbing system.

Understanding thread specifications is crucial for plumbing contractors, as they must select the correct fittings that will properly mate with existing pipes, maintaining consistency across a project. Other common pipe sizes have different thread counts as designated by NPT standards, and recognizing these differences enhances the overall proficiency in plumbing installation and repair tasks.