Per ASME Boiler and Pressure Vessel Code, how should expansion tanks be constructed?

The construction of expansion tanks according to the ASME Boiler and Pressure Vessel Code requires that they be certified. This certification indicates that the tank has been designed and constructed in compliance with specific recognized standards and safety regulations, ensuring its reliability and effectiveness in managing the thermal expansion of liquids within a plumbing or heating system.

By being certified, the expansion tank has undergone testing and quality assurance processes to demonstrate that it can withstand the pressures and temperatures it may encounter in service. The certification is crucial for safety in applications involving potentially hazardous conditions, as it helps prevent failures that could result in leaks or explosions.

While visibility, insulation, and portability may have their own considerations in certain applications, they do not directly align with the structural and compliance requirements set forth by the ASME Boiler and Pressure Vessel Code for expansion tanks.