What is the maximum operating limit of a low pressure steam boiler according to ASME?

The maximum operating limit of a low pressure steam boiler, as defined by the American Society of Mechanical Engineers (ASME), is 15 psig. This standard is significant because it differentiates low pressure steam systems from high pressure systems. Low pressure steam boilers are typically used in applications where steam is required for heating, humidification, or process heating at lower temperatures and pressures.

Understanding this limit is crucial for steamfitters and related professionals, as it dictates the design considerations, safety protocols, and operational procedures for these boilers. Operating above this threshold would classify the boiler as a high pressure steam boiler, which requires adherence to different, often more stringent regulations and safety measures.

Therefore, the identification of 15 psig as the maximum operating limit aligns with ASME standards and reflects the importance of maintaining safety and efficiency within steam heating systems.