What does Schedule 40 correspond to in terms of pipe wall thickness?

Schedule 40 corresponds to a standard pipe wall thickness, commonly used in plumbing and piping applications. This schedule designation indicates a specific thickness that ensures both strength and structural integrity for typical pressure conditions encountered in various systems.

When it comes to pipes, "schedule" refers to the wall thickness relative to the pipe diameter, which is key for determining how much pressure the pipe can withstand. Schedule 40 pipes are popular due to their balance of strength, weight, and the ability to be easily cut, fabricated, and handled during installation.

In contrast, welded or threaded references do not denote a specific wall thickness but rather the method of joining the pipes. Extra strong (XS) indicates a thicker wall than Schedule 40; therefore, it is not applicable here. The designation "standard" is indeed linked to Schedule 40; thus, recognizing that Schedule 40 is a common choice for standard applications helps solidify its role in piping standards.