How should underground piping joints be constructed?

Underground piping joints are best constructed using welded or press-connect fittings due to their strength and reliability. Welding creates a continuous, solid joint that is less likely to leak or fail over time, which is crucial for underground installations where accessibility for repairs can be challenging. Additionally, press-connect fittings offer a reliable connection without requiring fire, which can be advantageous in certain situations. These methods are designed to withstand the environmental pressures and potential ground movements that underground installations may face.

While other joining methods like screwed connections, bolted connections, or flexible joints have their applications, they often do not provide the same level of strength and security required for underground piping systems. Screwed connections can be more prone to leaks, while bolted connections may not offer the necessary seal against groundwater infiltration. Flexible joints, while useful in certain contexts, might not be suitable for all underground scenarios where stability is paramount.