Pipe joints for low-pressure water service Identify the joint most commonly used for pipes carrying water at low pressure. Choose the correct option.

Concept
Cast iron water mains and low-pressure water pipelines commonly use the spigot and socket (bell-and-spigot) joint, which provides alignment and sealing (traditionally with lead/yarn or rubber rings).

Elimination
Socket, nipple, and union joints are more typical for small-diameter screwed pipes and fittings, not for main low-pressure water lines.

Final Answer
Spigot and socket joint