Overview
ISO 13628-1:2005/Amd 1:2010 is an international standard issued by ISO that focuses on the design and operation of subsea production systems for the petroleum and natural gas industries. This amendment revises Clause 6 of Part 1, updating general requirements and recommendations regarding materials selection and corrosion protection for subsea equipment. This standard supports safe, reliable, and efficient offshore production by providing best practices for materials engineering in challenging subsea environments.
Key Topics
Materials Selection Principles
- Compliance with statutory and regulatory requirements is mandatory.
- The design lifetime, safety profile, operational reliability, and inspection strategy must guide material choices.
- Materials must withstand mechanical stresses, corrosive fluids, erosion, fatigue, and wear throughout the facility's life.
- Cost efficiency and material availability are important factors in final selection.
- The user defines specific application criteria, and agreements with suppliers may allow some flexibility in materials.
Corrosivity Evaluation
- Assessment includes all media in contact with system components, including:
- Seawater, produced fluids, hydraulic fluids, drilling/completion fluids, and chemical treatments.
- Internal corrosion evaluation covers hydrocarbon systems and injection systems (water/gas injection).
- Corrosive mechanisms such as hydrogen sulfide (H2S) attack, microbiologically influenced corrosion (MIC), and erosion-corrosion must be analyzed.
- External corrosion considerations include atmospheric, seawater, and cathodic protection environments.
Corrosion Control Measures
- Galvanic corrosion mitigation is essential when dissimilar metals are used, including cathodic protection and careful material pairing.
- Weld overlay techniques with corrosion-resistant alloys (CRAs) may replace more expensive homogeneous materials.
- Chemical treatments like corrosion inhibitors, oxygen scavengers, and biocides should be qualified and monitored for effectiveness.
- Cathodic protection systems are mandatory for subsea installations, covering painting/coatings combined with electrical protection techniques.
Materials Categorization and Definitions
- Clarifies terminology and classifications including:
- Carbon steel, low-alloy steel, corrosion-resistant alloys (CRAs), and common stainless steels like Type 316, 6Mo, and duplex steels.
- Emphasizes the importance of evaluating the Pitting Resistance Equivalent Number (PREN) for stainless steel selection, ensuring proper corrosion resistance in chlorinated environments.
Applications
- Subsea Production Systems: Ensures materials can withstand harsh subsea conditions such as high pressure, temperature variations, and corrosive environments typical in oil and gas extraction.
- Offshore Oil Platforms: Guides maintenance and operational reliability through material choices that reduce corrosion risks and increase lifespan.
- Injection Systems: Addresses the challenges of injecting water and gases for reservoir management, requiring corrosion-resistant materials and treatments.
- Pipeline Systems: Helps prevent internal and external corrosion in pipelines conveying hydrocarbons and treatment chemicals.
- Welded Assemblies: Provides critical specifications for corrosion-resistant weld overlays and mitigations during fabrication.
Related Standards
- ISO 15156 (NACE MR0175): Materials for use in H2S-containing environments in oil and gas production.
- ISO 21457: Corrosion control guidelines for offshore oil and gas production systems.
- ISO 12944: Corrosion protection of steel structures by protective paint systems.
- ISO 23936-1: Guidelines on non-metallic materials in contact with oil and gas media.
- ISO 8501 & ISO 8503: Preparation of steel substrates before coating application.
- EEMUA Publication 194: Recommendations on weld corrosion prevention and galvanic corrosion mitigation.
This amendment to ISO 13628-1 reinforces the importance of robust materials engineering and corrosion management in subsea production system design. Proper implementation ensures operational reliability, safety, and cost-effectiveness within the petroleum and natural gas offshore industry.
Open preview (PDF)Petroleum and natural gas industries — Design and operation of subsea production systems — Part 1: General requirements and recommendations — Amendment 1: Revised Clause 6