Definition(s)
Pdes
Purchaser nominated maximum pressure to which a piping system is designed to operate at the nominated design temperature (Tdes) and for the nominated design life (Ldes).
- Note: 1 to entry: Pdes is typically considered as a sustained pressure, though an additional Pdes occasional can also be nominated. Pdeswill be selected based on the maximum operating pressure plus a purchaser selected uplift a) to accommodate pressure uncertainty, b) to avoid triggering of pressure safety devices, c) to match the rating of attached piping or equipment and d) to provide a design margin for other purposes.
Source: ISO 14692-1:2017, Petroleum and natural gas industries — Glass-reinforced plastics (GRP) piping — Part 1: Vocabulary, symbols, applications and materials, Second Edition, August 2017. Global Standards