Overview
ISO 14617-8:2002 - "Graphical symbols for diagrams - Part 8: Valves and dampers" is an international standard published by ISO that defines standardized graphical symbols for valves and dampers used in technical diagrams. The part covers symbols for general-purpose valves, dampers, valves used in fluid power systems and hygienic valves for the food and pharmaceutical industries. It is intended for use in process plant documentation, piping & instrumentation diagrams (P&IDs), HVAC, and other technical schematics where unambiguous representation of valve and damper functions is required.
Key topics
- Scope and structure: Defines symbols and application rules for valves and dampers, and provides normative references and terms. Main sections cover general-purpose valves, dampers, fluid-power valves, hygienic valves and special-function valves.
- Basic symbols: Standardized pictograms for two-way, three-way and four-way valves and for two-/three-way dampers (e.g., symbol indexes such as 2101, 2103, 2151).
- Supplementary information symbols: Indicators for functions and construction - non-return/check, safety function, adjustability, preset adjustability, L-/T-bore patterns, globe/ball/plug/gate/needle/disc/diaphragm types, reduced bore, jacketed valves, etc.
- Application rules: Guidance on correct placement and composition of symbols, interaction with actuator symbols (referencing ISO 14617-4), representation of valve positions for fluid power systems, and conventions for showing flow direction and special states.
- Examples and use cases: Application examples (X-codes) showing typical combinations: safety valves, control valves (motor or diaphragm actuated), check valves, restrictor valves and dampers with actuators.
Practical applications
- Use ISO 14617-8 when creating or interpreting P&IDs, process flow diagrams, installation diagrams and maintenance documentation to ensure consistent, internationally understood valve/damper symbols.
- Beneficial for:
- Process, chemical and mechanical engineers
- CAD drafters and technical illustrators
- Plant designers and integrators of fluid power systems
- Food and pharmaceutical equipment designers (hygienic valve representation)
- Technical writers, safety assessors and regulatory bodies
- Main benefits: reduced ambiguity, clearer communication across suppliers and disciplines, improved compliance with international documentation practices, and more reliable maintenance and safety procedures.
Related Standards
- ISO 14617-1, -2, -4 (for general symbol indexes, common symbols and actuator symbols)
- ISO 81714-1 (design rules for graphical symbols)
- ISO/TC 10 and IEC collaboration for harmonized symbol libraries
Keywords: ISO 14617-8, graphical symbols for diagrams, valves and dampers, P&ID symbols, fluid power valves, hygienic valves, valve symbols standard.
