OCTG Grade Selector

Well depth (meters) Service environment Sweet (no H₂S)Sour (H₂S present — NACE MR0175) Collapse / internal pressure Low (<35 MPa)Medium (35–70 MPa)High (>70 MPa) Recommend grade →

Indicative API 5CT guidance only (yields per API Spec 5CT). Final grade depends on casing design, load case, and your engineer’s calculation — Synbase confirms availability, MTR, and sour-service certification on quotation.