ISO 6099:2018

Overview

ISO 6099:2018 - "Fluid power systems and components - Cylinders - Identification code for mounting dimensions and mounting types" establishes a uniform convention for identifying mounting dimensions, envelope dimensions, accessory and connector dimensions, and mounting/accessory types for fluid power cylinders (hydraulic and pneumatic). The standard provides an identification code system and reference-point rules so designers, manufacturers and specifiers can describe cylinder mounting and rod-end geometry consistently.

Key topics

• Identification codes for rod end types
  • Defines reference points (theoretical reference point - TRP) and letter codes for rod ends such as plain, pin, male/female threaded, grooved, and wrench-flat types (examples: RTM, RTF, RPE, RPR, RFE, RFS).
• Letter-code system for dimensions
  • Rules for two-letter codes that identify envelope and longitudinal dimensions (letters beginning with U, Z, W, X, Y). Special signs (+, ++, +/) indicate adding stroke, twice the stroke, or half the stroke.
• Mounting-type identification
  • Two- or three-letter plus number codes that identify mounting forms (examples: MB1 body-through-bolt, MF1 flange type, MP clevis types, MT trunnion types). Supports double-rod variants and envelope variations.
• Accessory identification and port position
  • Codes and conventions for accessory types and designation of port positions for round and square cylinders.
• Scope limits
  • The document creates a coding convention and uniform language; it is not a definitive list of every possible mounting/accessory type nor a dimensional interchangeability specification.

Applications

• Standardizes technical documentation, drawings and CAD libraries for fluid power cylinders.
• Facilitates clear procurement specifications and vendor quotations by using unambiguous mounting and rod-end codes.
• Speeds design reviews and integration of cylinders into machine assemblies by providing consistent reference points and dimensioning rules.
• Useful in technical catalogs, BOMs, maintenance manuals and interchangeability studies where consistent naming of mounting types and dimensions matters.

Who uses this standard

• Cylinder designers and OEM machine designers
• Pneumatics/hydraulics component manufacturers and suppliers
• Technical authors, CAD librarians and procurement/specification engineers
• Maintenance engineers and systems integrators

Related standards

• ISO 5598 (Fluid power systems and components - Vocabulary) - referenced for terminology.
• ISO 6099:2018 replaces the 2009 edition and was prepared by ISO/TC 131/SC 3 (Cylinders).

Using ISO 6099:2018 helps ensure consistent, searchable documentation for cylinder mounting dimensions and types - improving communication across design, manufacturing and purchasing workflows.