MEASURING PIPE AND TUBING.
a. Pipe. There are several ways to measure threaded pipe; therefore, it is
important to know which method is being used in any given measurement and to allow
for fitting dimensions (end-to-end or end-to-center) and for length of thread
engagement (fig 10 and 11).
Threaded pipe measurements.
Pipe thread data for standard pipe.
(1) End-to-end measure. End-to-end measure (1, fig 10) is the full length
of the pipe including both threads.
(2) End-to-center measure. End-to-center measure (2, fig 10) is used for a
piece of pipe having a fitting screwed on one end only. The pipe length is equal
to the measurement minus the end-to-center dimensions of the fitting plus the
length of thread engagement.