When performing a hydrostatic test on a boiler, what must be done with the safety valve?

During a hydrostatic test on a boiler, it is essential to ensure that the system is tested safely and effectively to evaluate its integrity under pressure. The correct procedure requires that the safety valve be removed and the opening blanked or gagged.

This is crucial because safety valves are designed to relieve excess pressure and prevent dangerous overpressure situations. If the safety valve were to remain in place during a hydrostatic test, it could potentially open or become damaged due to the pressure levels being used for the test, which are typically much higher than the valve's setpoint. Removing the valve not only protects it from damage but also ensures that the test accurately assesses the boiler's ability to handle operational pressures without interference from safety devices.

Gagging or blanking the opening prevents any chances of leakage and maintains the integrity of the test environment, allowing for a valid assessment of the boiler's integrity. Therefore, following this procedure is a standard and essential safety practice in boiler operation and maintenance.