What is the purpose of a muffler installed on a safety or relief valve?

The purpose of a muffler installed on a safety or relief valve primarily relates to the control of back pressure on a boiler. When steam or fluids are discharged from safety or relief valves, a sudden expansion can create subsequent issues, including back pressure that may affect the performance and safety of the boiler system. By installing a muffler, the flow of steam or fluids is managed more effectively, reducing the potential for back pressure, which could adversely impact the valve's ability to open correctly and relieve pressure as intended.

Back pressure can hinder the performance of the safety and relief valves by causing them to not reopen after discharging, or it may lead to incorrect pressure readings in the boiler system. Therefore, by controlling this back pressure, mufflers help to ensure that the relief valve operates reliably, maintaining the system's safety and efficiency.