API RP 14E

Covers — recommended practices for offshore production-platform topside piping: line sizing (including the erosional-velocity C-factor equation), erosion/corrosion considerations, material selection, and layout and installation.

Does NOT cover (exclusions) — the following are governed elsewhere:

• Baseline pressure design/stress analysis → ASME B31.3.
• The ISO equivalent → ISO 13703.
• Subsea pipelines → DNV-ST-F101 / ISO 13623; sand-erosion modeling → specialist erosion guidance (e.g., DNV-RP-O501).

RP 14E's C-factor is a screening limit; detailed erosion in sandy service needs a dedicated erosion model.

RP 14E provides recommended practices for offshore piping:

• Erosional Velocity — the C-factor equation limiting fluid velocity to reduce erosion in two-phase lines.
• Line Sizing — velocity/pressure-drop-based sizing for offshore service.
• Materials — selection for corrosive/erosive offshore conditions.
• Layout & Installation — arrangement and installation practices for platform piping.

API RP 14E is the classic recommended practice for offshore production-platform topside piping, best known for its erosional-velocity "C-factor" equation used to cap velocity in two-phase lines. It also covers line sizing, materials, layout, and installation, and is essentially mirrored by ISO 13703.

The C-factor is widely used but deliberately simple: it is conservative for clean service and does not directly model sand erosion or corrosion, so sandy or aggressive service typically needs a supplementary erosion model. Pressure design and stress analysis still come from ASME B31.3.

Engineering Note: Treat the RP 14E C-factor as a first-pass screening limit, not a precise erosion prediction — in sand-producing wells, size to a dedicated sand-erosion model, because the generic C-factor can be both too conservative for clean gas and unsafe for erosive service.