A safety valve on a boiler pops at what point in relation to working pressure?

The safety valve on a boiler is designed to protect the system from overpressure conditions by relieving excess pressure. It typically operates at a set pressure that is slightly above the normal working pressure but below the Maximum Allowable Working Pressure (MAWP) of the boiler. This ensures that, under normal operational conditions, the boiler can function safely without the risk of an overpressure event occurring.

When the boiler pressure exceeds the designated set point of the safety valve, the valve opens to relieve the pressure, which prevents potential damage to the boiler and associated equipment. If the valve were to pop only above the working pressure, the boiler would be at risk of experiencing excessive pressure scenarios that could lead to failure. Therefore, the correct understanding is that the safety valve "pops" or opens in a range that is above the working pressure but below the MAWP, thus ensuring safe operation within those parameters.