New Mexico Pipe Fitter Journeyman (JPF) Practice Exam

What is the recommended number of threads needed for hand and wrench engagement to create a leak-proof joint on a 1 inch pipe?

1. 11

2. 11.5

3. 12

4. 10

The correct answer is: 11.5

The recommended number of threads needed for hand and wrench engagement to create a leak-proof joint on a 1 inch pipe is 11.5 threads. This specific number ensures adequate engagement of the threads in order to form a strong and secure joint. A minimum of 11 threads ensures that there is enough surface area for the connection, while the additional half thread typically accounts for manufacturing tolerances and allows for a tight fit that helps prevent leaks. This attention to detail in the threading of pipes is critical for maintaining the integrity of the joint, especially in applications where pressure is involved. The importance of having this precise number of threads is rooted in the need for effective sealing. If there are too few threads engaged, the connection may be weak, leading to potential leaks.