12-1/4 inch 75# C-110 Sour Service Casing from Mexico
C-110 grade seamless alloy casing optimized for H2S sour service, 12-1/4 inch OD (311.2 mm within hierarchy), 75 lb/ft weight with thick walls ≥12.7 mm, full API STC couplings. Used to case wells with corrosive hydrogen sulfide content. Classified in 7304.29.31.40 for threaded, coupled, heavy-wall alloy steel oilfield casing.
Duty Rate — Mexico → United States
10%
Rate breakdown
9903.03.0110%Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
Import Tips
• Certify NACE MR0175/ISO 15156 compliance for sour service; declare sulfide stress cracking test data
• Common issue: incorrect alloy content declaration affecting duty rates
• Bundle lengths must be specified (typically 40 ft)