Maximum allowable working pressure (MAWP)
The maximum gauge pressure pennitted at the top of a pressure vessel in its operating position for a designated temperature. This pressure is based on calculations using the minimum (or average pitted) thickness for all critical vessel elements, (exclusive of thickness designated for corrosion) and adjusted for applicable static head pressure and non-pressure loads, e.g. wind, earthquake, etc.
Source: API 510, Pressure Vessel Inspection Code: In-Service Inspection, Rating, Repair, and Alteration Downstream Segment, Ninth Edition, June 2006. Global Standards
Maximum anticipated wellhead pressure.
Source: API Bulletin 97, Well Construction Interface Document Guidelines, First Edition, December 2013. Global Standards
Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards
Maximum anticipated wellhead pressure (for subsea wells).
Source: API STD 53, Blowout Prevention Equipment Systems for Drilling Wells, Upstream Segment, Fourth Edition, November 2012. Global Standards