Two reason why I would use the ASME Boiler and Pressure Vessel Code for design and fabrication requirements of supercritical boilers. The design margin for ASME B&PV code is 3.5 to 1, versus European codes that use a slightly lower design margin. The second reason is that it is an accepted and proven international code for boiler and pressure vessel construction.
In addition, please note that the location or Jurisdiction where you would have the supercritical boiler installed may have specific Codes or Standards requirements that you would need to follow for boiler construction.
The location of the installation and the selection of hardware fabricators will determine the selection fo the code.
IN the USA and some other areas , ASME is legally required. If the financing monies are sourced from the USA , then it is likely that there will be cost advantages to source a major part fo the hardware from ASME shops that might not be qualified by the EU PED.
Having said that , there have been very few supercritical units built using the ASME code after 1980 . Many of the provisions of the ASME sect I code are directly applicable to technology that is outdated and does not reflect the latest global technology. In particular:
a) ASME sect I does not recognize the existence of fatigue damage- talk about the elephant behind the curtains!
b)ASME I does not provide explicit guildelines for weld creep strength reduction factors for advanced alloys, which would be used in modern advanced cycle units.
c) ASME I relief valve requirements are addressing older technology units which use "boiler division valves" or PRV's halfway thru the boiler circuitry, and actually permit as low as 15% MCR releif capacity of relief valves ( so called state specials), and does not permit the use of HP bypass valves as the code required safety valve. Modern once thru nits do not buse boiler division valves and there aer some special HP bypass valves which can be used as safety valves ( TRD).
