Overview
ISO 18464:2025 - Hydraulic fluid power - Design methodology for energy efficient systems - specifies a structured design methodology to minimise the energy consumption of hydraulic systems while maintaining required machine functionality. It applies to stationary and mobile machinery and requires designers to account for application duty cycles (definition of duty cycles is outside the standard). The document treats the hydraulic system including prime movers within the system boundary and focuses on energy performance during operation.
Key topics and technical requirements
- Design methodology and process: A stepwise approach that integrates energy consumption as a primary design criterion alongside functional requirements.
- Duty-cycle based design: Actuator and control design must be based on time transients of force/speed (linear actuators) or torque/rotation speed (rotary actuators).
- Actuator dimensioning: Select and size actuators to match load and speed requirements - avoid oversizing and aim to minimise the difference between working and supply pressure.
- Control strategies: Use pump flow rate control or adjust system supply pressure to match demand. Prioritise recovery and regenerative concepts where applicable and minimise control/auxiliary power (e.g., PWM to reduce holding current).
- Hydraulic power supplies: Feed only the hydraulic energy required by the duty cycle; use prime mover speed control with fixed/variable displacement pumps; avoid prolonged idle pump operation; consider accumulators for peak power when net energy savings are achieved.
- Power distribution (piping): Design for laminar flow, avoid abrupt diameter changes, prefer bent pipes over elbow connectors to reduce pressure loss (see Annex B for recommendations).
- Hydraulic fluid selection: Choose the lowest practical viscosity meeting functional and temperature-range requirements while respecting component manufacturer guidance and wear considerations.
- Auxiliary components: Account for cooling/heating, filters, sensors and valves; dimension for minimal pressure loss.
- Energy calculation and rating: Provides an energy accounting method over duty cycles, including recuperated energy and energy stored in accumulators, using integrals of primary power supply and recuperation transients; component efficiency maps should be considered.
Applications and users
ISO 18464:2025 is intended for:
- Hydraulic system designers and OEMs (mobile and stationary machinery)
- System integrators and control engineers optimizing energy performance
- Product managers and sustainability engineers targeting reduced operational energy use
- Procurement and compliance teams evaluating energy-efficient hydraulic solutions
Typical machine applications include presses, clamps, heavy-motion drives (e.g., excavators), hydrostatic transmissions and mass compensation systems.
Related standards
- ISO 5598 - Fluid power systems and components - Vocabulary (normative reference used by ISO 18464).
- Prepared by ISO/TC 131 (Fluid power systems), Subcommittee SC 9 (Installations and systems).
Keywords: ISO 18464, hydraulic fluid power, energy efficient systems, hydraulic systems design, duty cycles, actuator dimensioning, hydraulic power supplies, piping design, hydraulic fluid viscosity.