Where does failure due to thermal expansion and contraction usually occur in piping systems?

The occurrence of failure due to thermal expansion and contraction in piping systems is most commonly found at the pipe joints and fittings. This is primarily because these areas are often where different materials meet and where movement can take place. Joints and fittings are typically more susceptible to stress since they are designed to connect different sections of the piping system, and any expansion or contraction in the pipe can lead to strain at these connection points.

Thermal expansion causes pipes to lengthen when heated and contract when cooled. If these movements are restricted—due to rigid connections or lack of appropriate expansion joints—it can lead to leaks or even failures at the joints. In contrast, other areas of the piping, such as the material itself or within the valves, may have more robust and uniform structural integrity to withstand thermal changes, making them less prone to failure due to temperature variations.