The new code uses eight fields: Seal category Seal arrangement Seal type Containment device Gasket material Face material Approximate shaft size (in millimeters) Piping plan As an example, the 4th Edition code might be 31B-LIN-075-53A to indicate: 3 – Category 3 1 – Arrangement 1 B – Type B seal L – Floating bushing I – FFKM secondary seals N – Carbon vs reaction bonded silicon carbide 075 – installed on a 75 mm shaft 53A – Plan 53A Piping plans Annex G provides illustrations and a short tutorial about each piping plan. As has been the case for every edition, changes were made to the standard piping plans. In particular, the piping plans now default to using transmitters with local indicators as part of the instrumentation. Future editions API standards are reviewed every five years and re-issued every ten years. A new Taskforce for API 682 was formed in 2017 and preparations for 5th Edition are underway. References Seals (mechanical) Oil industry standards American Petroleum Institute