ISO 4393:2015

Overview

ISO 4393:2015 - "Fluid power systems and components - Cylinders - Basic series of piston strokes" defines a preferred series of piston stroke lengths for single‑acting and double‑acting fluid power cylinders. The standard is aimed primarily at pneumatic cylinders but is also applicable to hydraulic cylinders. It provides a consistent set of stroke values, identification guidance and references for terminology and numerical series selection to support design, manufacturing and procurement.

Key topics and requirements

• Scope: Specifies the preferred series of piston strokes for fluid power cylinders (single‑acting and double‑acting). Mainly for pneumatic cylinders, optionally for hydraulic cylinders.
• Preferred stroke series: Recommends the basic series S of stroke lengths. Values included in ISO 4393:2015 are: 5, 10, 25, 50, 80, 100, 125, 160, 200, 250, 320, 400, 500 mm.
• Dimensions & identification: Stroke identification refers to a standard figure for piston stroke dimensions; manufacturers should select strokes from the preferred series.
• Terminology: Uses terms and definitions referenced from ISO 5598 (Fluid power - Vocabulary).
• Extension note: If the series needs expanding, the standard advises using rounded values from the R10 series as indicated in ISO 497.
• Manufacturer recommendation: Includes a recommended identification phrase for use in test reports, catalogs and commercial documentation to state conformance with ISO 4393.

Applications and who uses it

ISO 4393:2015 is practical for:

• Manufacturers of pneumatic and hydraulic cylinders standardizing product ranges and catalog entries.
• Design engineers selecting stroke lengths to match system travel requirements and promote interchangeability.
• Procurement and application engineers specifying standard stroke options to reduce custom machining and costs.
• System integrators and maintenance teams who need consistent replacement parts and documentation. Practical benefits include simplified ordering, improved parts interchangeability, easier inventory management, and clearer technical documentation.

Related standards

• ISO 5598 - Fluid power systems and components - Vocabulary (terminology used by ISO 4393).
• ISO 497 - Guide for choosing series of preferred numbers and rounded series (used when extending the stroke series).
• Developed by ISO/TC 131 (Fluid power systems and components) - useful cross‑reference for broader cylinder and fluid power standards.

Keywords: ISO 4393:2015, fluid power, piston strokes, cylinder stroke series, pneumatic cylinders, hydraulic cylinders, preferred stroke series, ISO 5598, ISO 497.