ISO 11960:2020

Overview

ISO 11960:2020 - Petroleum and natural gas industries - Steel pipes for use as casing or tubing for wells - defines the technical delivery conditions for steel pipes, coupling stock, coupling material and accessory material used as casing, tubing and pup joints in oil and gas wells. The sixth edition (2020) covers a wide range of pipe grades (H40, J55, K55, N80, L80, C90, R95, T95, P110, C110, Q125) and common field connections (SC, LC, BC, NU, EU, IJ). By purchaser–manufacturer agreement it can be extended to other plain-end sizes and non‑standard connections.

Key topics and requirements

ISO 11960:2020 focuses on the practical, quality and inspection requirements for well tubulars without specifying thread dimensions (see API Spec 5B for gauging and thread dimensions). Major technical topics include:

• Material and metallurgical requirements: chemical composition, grain size and hardenability for specific grades.
• Mechanical properties: tensile properties, yield/elongation and statistical tensile testing for selected grades.
• Toughness and impact testing: Charpy V-notch test requirements, specimen hierarchy, test temperatures and statistical impact testing.
• Hardness control: maximum hardness, hardness variation and process control for higher grades.
• Heat treatment and manufacturing processes: requirements for quenching/tempering, straightening, welding and processes that require validation.
• Corrosion and sulfide stress cracking (SSC): SSC testing provisions and selection guidance for susceptible grades.
• Dimensional and physical tolerances: diameter, wall thickness, mass, length, straightness, end finishes and defect disposition.
• Couplings and thread protection: delivery conditions for couplings, coupling stock and thread protection for the listed connections.
• Traceability and serialization: marking and traceability requirements, especially for higher strength grades.

Applications and users

ISO 11960 is essential for stakeholders in the upstream oil and gas sector who require consistent, auditable specifications for tubulars:

• Pipe manufacturers and foundries - to set production processes, heat treatment and inspection regimes.
• Oil & gas operators and drilling contractors - to specify purchase requirements for casing and tubing.
• Procurement and quality assurance teams - to verify delivery, traceability and conformance.
• Inspection and testing laboratories - to perform tensile, Charpy, hardness and SSC testing in accordance with standard requirements.
• Coupling and accessory suppliers - for compatibility with coupling stock, thread protection and accessory materials.

Related standards

• API Spec 5B - thread dimensions, gauging practice and thread inspection methods (ISO 11960 excludes threading requirements and references API 5B).
• ANSI/NACE TM0177 - referenced for additional SSC testing methods and guidance.

Keywords: ISO 11960:2020, steel casing, tubing specifications, well casing standards, oil and gas tubulars, API Spec 5B, Charpy V-notch, sulfide stress cracking, pipe grades P110, casing couplings.