Views: 0 Author: J-VALVES Publish Time: 2025-02-26 Origin: Site
ISO 14313 is a widely recognized standard that specifies the requirements for pipeline valves used in the petroleum and natural gas industries. It covers a range of valve types, including check valves, and provides detailed guidelines for material selection, design, and testing to ensure valves can withstand harsh operating conditions.
1. Scope: Defines the range of valve sizes and pressure ratings covered by the standard.
2. Design and Manufacture: Specifies detailed requirements for the design and manufacturing of the valves, including body ends, body tappings, and connections.
3. Materials: Outlines the choice of materials for different components of the valve.
4. Testing and Inspection: Provides protocols for testing and inspection to ensure the valves meet the required performance standards.
5. Marking: Specifies the marking requirements for the valves, including general markings, body markings, and identification plate markings.
Sulphur-Resistant Materials in Check Valves
• Shell and Bonnet: Typically made from carbon steel or low-alloy steel, with specific grades chosen to resist sulphur-induced stress corrosion cracking (SCC).
• Disc: Made from materials such as stainless steel or other corrosion-resistant alloys to ensure durability in sulphur-containing environments.
• Seat Ring: Often made from bronze or stainless steel, which provide excellent corrosion resistance and sealing performance.
• Hinge Pin: Stainless steel is commonly used for its corrosion resistance and mechanical strength.
• Corrosion Resistance: Materials must be selected to resist corrosion from hydrogen sulfide and other corrosive substances present in natural gas.
• Mechanical Properties: The materials must meet specific mechanical properties, such as tensile strength and hardness, to ensure the valve can withstand operational stresses.
• Thermal Treatment: Some materials may require specific heat treatment processes to enhance their resistance to SCC.
• Material Selection: For natural gas pipelines containing H₂S, materials such as 316L stainless steel or alloy 625 are often specified due to their excellent resistance to SCC.
• Design Requirements: The design must ensure that all components, including the shell, bonnet, disc, and seat ring, are made from materials that can withstand the corrosive environment.
• Testing and Certification: Valves must be tested and certified to meet the requirements of ISO 14313, including specific tests for sulphur resistance.
• Material Selection: In oil and gas processing plants, materials such as duplex stainless steel may be used for their high strength and corrosion resistance.
• Design Requirements: The design must account for the potential presence of corrosive substances, including H₂S, and ensure that all components are made from appropriate materials.
• Testing and Certification: Valves must undergo rigorous testing to ensure they meet the performance and safety standards specified by ISO 14313.
| Feature | Standard Cast Iron Valves | Sulphur-Resistant Valves |
| Material | Cast iron or ductile iron | Stainless steel, alloy steels |
| Corrosion Resistance | Limited resistance to H₂S | Excellent resistance to H₂S |
| Mechanical Properties | Standard mechanical properties | Enhanced mechanical properties for SCC resistance |
| Applications | General industrial use | Natural gas pipelines, oil and gas processing |
| Testing Protocols | Standard hydrostatic and pneumatic tests | Additional corrosion resistance tests |
