Definition(s)
Pressure Boundary
The portion of the piping that contains the pressure retaining piping elements joined or assembled into pressure tight fluid-containing piping systems. Pressure boundary components include pipe, tubing, fittings, flanges, gaskets, bolting, valves, and other devices such as expansion joints and flexible joints.
- NOTE: Also see non-pressure boundary definition.
Source: API 570, Piping Inspection Code: In-service Inspection, Rating, Repair, and Alteration of Piping Systems, Fourth Edition, February 2016, with Addendum May 2017. Global Standards
Pressure Boundary
That portion of the pressure vessel that contains the pressure retaining elements joined or assembled into a pressure tight, fluid-containing vessel (e.g. typically the shell, heads, and nozzles but excluding items such as supports, skirts, clips, etc. that do not retain pressure).
Source: API 510, Pressure Vessel Inspection Code: In-service Inspection, Rating, Repair, and Alteration, Tenth Edition, May 2014, with Addendum May 2017. Global Standards
Pressure Boundary
The portion of the vessel that contains the pressure e.g. typically the shell, heads and nozzles.
Source: API 510, Pressure Vessel Inspection Code: In-Service Inspection, Rating, Repair, and Alteration Downstream Segment, Ninth Edition, June 2006. Global Standards