Homogenisation of multi-grade crude blends before custody transfer metering to ensure a representative sample at the fiscal metering point per ISO 3171.
Coefficient of Variation (CoV) ≤0.05 at ISO 3171 sampler location (typically 5–10D downstream). Blend uniformity must be maintained across full viscosity range of crude stocks throughout the year. Pigging frequency and mixer design must be compatible.
Preferred MOC: Carbon steel standard (ASTM A105/A106). Duplex 2205 for sour crude (Hydrogen Sulphide (H₂S) service, NACE MR0175). ATEX-rated housing with bonding/earthing connections.
ATEX Zone 1 — ATEX (Ex-zone rated) certified equipment and documentation mandatory. Piggable VN with extractable vane assembly for trunk line pigging. Sampling probe per ISO 3171 located 5–10D downstream of mixer. Heat tracing if wax appearance temperature > ambient.