ISO 11727:1999 PDF

Overview

ISO 11727:1999 - Pneumatic fluid power - Identification of ports and control mechanisms of control valves and other components provides a standardized system for marking and identifying ports, control mechanisms and electrical leads on pneumatic control valves and common ancillary devices. The standard helps ensure consistent port numbering and labelling on directional control valves, filters, regulators, lubricators, non‑return (check) valves, flow control valves and similar components used in pneumatic systems.

Key topics and requirements

• Port identification system
  • Main ports use single‑digit numbers (e.g., 1, 2, 3).
  • Control mechanisms and pilot control ports use two‑digit identifiers beginning with “1” (e.g., 12, 14). The second digit indicates the main port that communicates with main port 1 when the control is actuated; a “0” is used where actuation blocks main port 1.
  • External pilot supply ports are identified by the letter X when a separate port is provided.
• Electrical leads / solenoid identification
  • Options include direct visual identification (leads attached to solenoid), colour‑coding at field connections, or markings on terminal blocks/wires using the two‑digit identifiers.
• Device‑specific rules
  • Quick exhaust, shuttle, lockout, flow control, check and relief valves have defined port numbering (e.g., inlet = 1, outlet/exhaust = 2, relief = 3).
  • Filters, lubricators and regulators may be marked by numbers (1 inlet, 2 outlet) or by a flow‑direction arrow.
• Manifold and assembly marking
  • Manifold sections and end plates must use the same port/control identifications as individual valves; multiple identifications are permitted when ports change function depending on assembly.
• Optional and omitted markings
  • Pilot exhaust ports need not be marked. Some devices may employ arrows instead of numeric marks.
• Exclusions
  • The standard does not apply to proportional valves, air logic valves, cylinders, air motors, semi‑rotary actuators, compressors, dryers or other devices not listed.

Practical applications

• Use ISO 11727:1999 to ensure consistent labelling in:
  • Pneumatic valve design and manufacturing
  • System schematics, product catalogues and technical data sheets
  • Manifold assembly layout, installation and maintenance documentation
  • Control panel wiring and field wiring instructions
• Benefits: reduces installation errors, simplifies troubleshooting, and improves interchangeability of components across vendors.

Who should use this standard

• Pneumatic and automation designers, valve manufacturers, system integrators, maintenance engineers, technical authors, and purchasers specifying pneumatic components.

Related standards

• ISO 5598 (fluid power vocabulary)
• ISO 5599‑1/2/3 (valve symbol precedence referenced)
• ISO 1219‑1 (graphical symbols - Annex A uses these symbols)

Use the identification statement in documentation: “Ports and control mechanisms of pneumatic control valves and other components identified in accordance with ISO 11727:1999.”