ISO 11961:2018 PDF

Overview

ISO 11961:2018 - Petroleum and natural gas industries - Steel drill pipe specifies technical delivery conditions for steel drill-pipes with upset pipe-body ends and weld‑on tool joints used in drilling and production operations. It defines requirements for three Product Specification Levels (PSL‑1, PSL‑2, PSL‑3), covers multiple material grades (E, X, G, S, D, F), and provides dimensions and masses in both SI and USC units. The standard can be applied to tool joints outside ISO/API specifications or to alternative dimensions by purchaser–manufacturer agreement. Note: ISO 11961:2018 does not address in‑service performance degradation.

Key topics and technical requirements

• Product specification levels (PSL‑1, PSL‑2, PSL‑3) - PSL‑1 is the baseline; Annex G defines increased technical requirements for PSL‑2 and PSL‑3.
• Grades covered - grade E (standard), high‑strength grades X, G, S, and enhanced H2S‑resistant grades D and F.
• Geometry and mass - standard drill‑pipe configurations, main dimensions and masses (SI and USC), alternative configurations permitted by agreement.
• Welded tool joints & weld‑zone controls - welding qualification, weld‑zone profile, post‑weld heat treatment, weld machining and inspection.
• Material and mechanical testing - tensile tests, hardness tests (surface and through‑wall), Charpy V‑notch impact tests, transverse side‑bend tests; sulfide stress cracking testing for grades D and F.
• Non‑destructive examination (NDE) - wet fluorescent magnetic‑particle inspection, ultrasonic inspection procedures, defect disposition and system capability records.
• Manufacturing and process control - processes requiring validation, traceability, lot sizing, sampling, and defect handling.
• Marking and documentation - marking, traceability IDs, retention of records, and minimum facility/documentation requirements.
• Optional supplementary requirements - Annex E lists additional testing and verification options that can be agreed contractually.

Applications and who uses this standard

ISO 11961:2018 is used by:

• Drill‑pipe manufacturers for production control, welding procedure qualification, NDE and traceability systems.
• OEMs and equipment fabricators specifying drill‑pipe geometry and materials.
• Operators and service companies for procurement, acceptance testing, and contract specifications in oil & gas drilling and production.
• Quality, inspection and NDE teams to establish test frequencies, sampling plans and defect disposition rules.
• Procurement and contracting to define PSL levels, supplementary requirements, and acceptance criteria.

Practical uses include preparing purchase orders, defining factory inspection/testing protocols, and ensuring consistent marking and documentation for traceability.

Related standards

• ISO 10424‑2 / API Spec 7‑2 - detailed threading requirements for tool joints (referenced).
• API RP 7G - guidance on drill‑pipe performance properties (referenced for performance aspects not covered by ISO 11961).