Which test is commonly performed to ensure the quality of welds in pressure piping systems?

Non-destructive testing (NDT) is the correct answer because it allows for the assessment of weld quality in pressure piping systems without causing any damage to the weld itself. NDT methods, such as ultrasonic testing, radiographic testing, and magnetic particle testing, enable inspectors to identify defects, discontinuities, or weaknesses in the welds without compromising the integrity of the piping. This is crucial in ensuring safety and reliability in pressure piping systems, as the consequences of a faulty weld can lead to catastrophic failures.

Visual inspection, while useful, typically serves as an initial assessment to identify obvious surface issues but does not adequately assess the internal integrity of welds. Destructive testing, involving the destruction of sample welds to examine their properties, is not practical for all welds in a live system. Thermal testing is generally more related to evaluating temperature performance or thermal expansion rather than directly assessing weld quality. Therefore, non-destructive testing remains the preferred method for evaluating weld integrity in pressure piping systems.