Overview
ISO 6368:2021 is an international standard developed by ISO for dry gas sealing systems used in axial, centrifugal, and rotary screw compressors and expanders. Primarily designed for the petroleum, petrochemical, and natural gas industries, this standard provides guidelines to optimize the selection and application of dry gas seals to ensure operational safety and efficiency. It is a supplement to API Std 692 (1st edition, 2018), aligning closely with international practices while incorporating specific exceptions and references to other ISO standards. This document supersedes ISO 10438-4:2007, reflecting the latest industry requirements.
The scope covers diverse installations such as oil refineries, gas plants, LNG facilities, petrochemical complexes, and oil and gas production sites. It excludes other types of shaft sealing methods like clearance seals, restrictive ring seals, or traditional oil seals, focusing solely on dry gas sealing solutions relevant to compressor and expander equipment defined in ISO 10439 and ISO 10440 series.
Key Topics
- Dry Gas Sealing Systems: Guidelines for dry gas seals used in high-performance axial, centrifugal, and rotary screw compressors and expanders, emphasizing leak prevention and reliability.
- Supplement to API Std 692: ISO 6368 complements API Std 692 standards by adapting specific requirements with references to ISO standards for materials, components, and system design.
- Materials and Metallurgy: Specification for metals used in sleeves, retainers, housings, disks, and carriers, referencing ISO 17945 for corrosion resistance and ISO 15156 for materials in H2S environments.
- Pressure Control and Relief: Detailed criteria for pressure-relieving devices based on ISO 23251 and ISO 4126 standards, ensuring protection against excessive pressure within the sealing system.
- Valves and Coolers: Application of ISO standards for valves (ISO 10434, ISO 15761, ISO 17292) and coolers (ISO 13706, ISO 16812) replacing corresponding API standards to maintain consistency across equipment components.
- System Diagrams: Use of ISO 10439-2 for system layout and diagrammatic representations to support proper installation and maintenance.
- Industry-Specific Adaptations: Tailoring general sealing system requirements to the unique operational contexts of the oil, gas, and petrochemical sectors.
Applications
ISO 6368:2021 serves as a critical reference for engineers, equipment manufacturers, and facility operators involved in:
- Petroleum Refining: Ensuring the integrity and efficiency of compressor seals in crude oil processing and refining operations.
- Petrochemical Production: Supporting safe and reliable compressor sealing systems in chemical feedstock processing plants.
- Natural Gas Processing: Enhancing seal performance to prevent leaks and environmental contamination in gas treatment and compression.
- LNG Facilities: Application of dry gas seals in liquefied natural gas equipment to maintain system safety under cryogenic conditions.
- Oil and Gas Extraction: Managing robust sealing solutions for compressors in offshore and onshore production facilities where reliability and safety are paramount.
- Equipment Design and Maintenance: Facilitating proper selection, installation, and maintenance of dry gas sealing components adhering to international best practices.
Related Standards
ISO 6368 references and supplements a network of standards critical to the petroleum and natural gas industries, including:
- API Std 692 (2018) – Base standard for dry gas sealing systems which ISO 6368 supplements.
- ISO 10439 (all parts) – Covers axial and centrifugal compressors and expanders, essential for defining compressor types.
- ISO 10440-1 and ISO 10440-2 – Address rotary-type positive displacement compressors.
- ISO 17945 – Specifies materials resistant to sulfide stress cracking for corrosive environments.
- ISO 15156 (all parts) – Materials selection for H2S-containing environments.
- ISO 23251 – Pressure-relieving and depressuring systems.
- ISO 4126 (all parts) – Safety devices for protection against excess pressure.
- ISO 10434, ISO 15761, ISO 17292 – Standards governing various valve types applicable to sealing systems.
- ISO 13706, ISO 16812 – Standards for heat exchangers relevant to seal coolers.
- ISO 10497 – Fire type-testing requirements for valves.
ISO 6368:2021 enhances the safety, reliability, and operational effectiveness of dry gas sealing systems within essential energy and chemical industries by integrating rigorous international requirements with practical engineering guidance. Organizations involved in the design, operation, and maintenance of compressor equipment will benefit from adherence to this standard to mitigate sealing risks and ensure compliance with industry best practices.