ISO 5211:2023

Overview

ISO 5211:2023 - Industrial valves - Part-turn actuator attachments - defines the mechanical interface between part-turn actuators (with or without gearboxes) and industrial valves or intermediate supports. The third edition (2023) standardizes flange geometry, driving-component dimensions, reference torque values and designation conventions so actuators and valves from different suppliers can be matched reliably. Attachment of intermediate supports to the valve itself is explicitly out of scope and control-valve attachments require purchaser‑supplier agreement.

Key topics and technical requirements

• Flange dimensions and mounting: specifies standard flange types (F03 … F100), bolt/stud arrangements, hole positions and minimum flange sections. Flange tables (with figures) give diameters, bolt sizes and hole spacing to ensure consistent mounting interfaces.
• Maximum flange torques: provides reference maximum torques for each flange type, ranging from low values (e.g., F03 = 32 Nm) up to very large values (e.g., F100 = 1 000 000 Nm). These values are calculated for bolts in tension at 290 MPa with a 0.2 friction coefficient; Annex A explains the calculation method.
• Drive and driven component geometry: defines dimensions for various drive forms to ensure correct engagement and clearance:
  • key(s) (single or multiple)
  • parallel or diagonal square head
  • flat head and improved flat head
  • involute spline
  • bi-square Detailed dimensions, positions and tolerances are covered (including a new Annex B for key/keyway dimensions).
• Designation system: standard format for identifying attachment interfaces (e.g., ISO 5211 – F05 Y – V – 18), indicating flange type, spigot presence and drive type/dimensions.
• Installation considerations: guidance on depth of engagement, contact area, material strength and limiting driven-component length to avoid interference or overstress.

Practical applications and users

ISO 5211:2023 is used by:

• Valve manufacturers - to provide standardized mounting flanges and driven components so valves accept common actuators.
• Actuator and gearbox suppliers - to design actuator drives that mate with industry-standard valve interfaces.
• Procurement and OEMs - to specify compatible actuator‑valve combinations in tender documents and engineering schedules.
• Plant engineers and maintenance teams - to replace or upgrade actuators without custom adaptors, reducing downtime and spare-parts complexity.

Benefits include improved interchangeability, predictable torque transmission, simplified procurement and safer, more reliable actuator‑to‑valve connections.

Related standards

• ISO 273 (clearance holes for bolts and screws) - referenced for hole tolerances
• ISO 5210:2023 - for related multi-turn actuator/gearbox interfaces

Keywords: ISO 5211:2023, industrial valves, part-turn actuator attachments, flange dimensions, torque values, actuator‑valve interface, drive types, keyway dimensions.