ISO 23840:2021 PDF

Overview

ISO 23840:2021 - Water hydraulics - Water-hydraulic pumps - Methods of testing and representing basic steady-state performance defines standardized methods to measure and present the steady‑state performance and efficiency of water‑hydraulic positive displacement pumps with continuously rotating shafts. The standard covers required test equipment, a prescribed test circuit, preparation and measurement procedures, and rules for presenting test results for pump performance testing using tap water as the working fluid.

Key topics and requirements

• Scope: Tests apply to water‑hydraulic positive displacement pumps; results include performance and efficiency under steady‑state conditions.
• Test fluid: Tap water only; no additives. Filtration to 10 μm is required before the hydraulic tank.
• Test circuit: A specified circuit (Figure 1) including pump under test, torque meter, tachometer, boost pump, relief valves, flowmeter and heat exchanger. Installation rules address tank height (above pump suction) and prevention/removal of air entrainment.
• Measurements required: Effective torque, rotational frequency (n), flow rate (q), inlet and outlet gauge pressures (pi, pe), and water temperature (Tw).
• Temperature control: Tests carried out at stated temperature measured at tank or pump inlet; recommended range 20 °C to 40 °C. Temperature accuracy classes A/B/C correspond to tolerances ±1.0 °C / ±2.0 °C / ±4.0 °C (see Annex A).
• Test procedure: Detailed preparation (start‑up, leak and vibration checks, pressurization sequence) and measurement steps covering the full working rotational frequency and outlet pressure ranges. Steady‑state readings must be within permissible variation (Annex B).
• Results presentation: Requirements for expressing performance, volumetric and hydromechanical efficiencies, derived capacity and torque, and example graphical formats (Annex C).

Applications and who uses it

• Pump manufacturers - to certify and publish consistent performance data for water‑hydraulic pumps.
• Test laboratories - to build compliant test rigs and produce repeatable, accredited test reports.
• System designers & integrators - to select pumps and size components in clean applications (food, packaging, semiconductors, cosmetics, animal/plant systems).
• Procurement & compliance teams - to compare suppliers using standardized performance metrics.
• R&D and QA - to validate design changes, efficiency improvements and quality control using standardized steady‑state tests.

Related standards

• ISO 4391 - Hydraulic fluid power - Pumps, motors and integral transmissions - Parameter definitions and letter symbols.
• ISO 5598 - Fluid power systems and components - Vocabulary.

Keywords: ISO 23840:2021, water hydraulics, water‑hydraulic pumps, pump testing, steady‑state performance, pump efficiency, flow rate, test procedure, positive displacement pumps.