The most vulnerable parts of oilfield machinery are the machined metal surfaces—flanges, shafts, and threads. API 11P categorizes preservation based on the intended storage duration (short-term vs. long-term). It specifies the types of rust preventatives (RP) to be used, distinguishing between hard-dry films, oil-based coatings, and volatile corrosion inhibitors (VCI).
Invest in the official 3rd Edition PDF from API. Keep it on your desktop, tablet, and server. Mark it up. Cross-reference it with your P&IDs. Train your junior engineers on Clause 6 (valves) and Clause 9 (controls). api 11p pdf