ASTM D7721 - 17

    Standard Practice for Determining the Effect of Fluid Selection on Hydraulic System or Component Efficiency

    Active Standard ASTM D7721 | Developed by Subcommittee: D02.N0

    Book of Standards Volume: 05.04


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    Significance and Use

    5.1 The purpose of a hydraulic fluid is to cool and lubricate fluid power components, as well as transmit power. This practice provides uniform guidelines for comparing fluids in terms of their power-transmitting abilities as reflected in their effect on hydraulic system or component efficiency. Standard test methods ISO 4409 and ISO 4392 provide specifications for evaluating the steady state performance of hydraulic pumps and motors but do not address technical requirements specific to hydraulic fluid testing.

    5.2 Differences in fluid performance may be relatively small. Consequently, it is essential that the necessary experimental controls are implemented to ensure consistency in operating conditions and duty cycle when comparing the energy efficiency of different hydraulic fluid formulations.

    5.3 Practical advantages of enhanced hydraulic system efficiency may include increased productivity (faster machine cycle time), reduced power consumption (electricity or fuel), and reduced environmental impact (lowered emissions).

    5.4 This practice implies no evaluation of hydraulic fluid quality other than its effect on hydraulic system efficiency.

    1. Scope

    1.1 This practice covers all hydraulic fluids.

    1.2 This practice is applicable to both laboratory and field evaluations.

    1.3 This practice provides guidelines for conducting hydraulic fluid evaluations. It does not prescribe a specific efficiency test methodology.

    1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

    1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

    1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.


    2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

    ASTM Standards

    D4174 Practice for Cleaning, Flushing, and Purification of Petroleum Fluid Hydraulic Systems

    D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants

    ISO Standards

    ISO 4391 Hydraulic fluid powerPumps, motors and integral transmissionsParameter definitions and letter symbols

    ISO 4392 Hydraulic fluid powerDetermination of characteristics of motors

    ISO 4409 Hydraulic fluid powerPositive displacement pumpsMethods of testing and presenting basic steady state performance

    ISO 5598

    ISO 8426 Hydraulic fluid powerPositive displacement pumps and motorsDetermination of derived capacity

    Other Standards

    VDI 2198 Type Sheets for Industrial Trucks Available from Verein Deutscher Ingenieure (VDI) (The Association of German Engineers), VDI-Platz 1, 40468 Dsseldorf, Germany, www.vdi.de.


    ICS Code

    ICS Number Code 75.120 (Hydraulic fluids)

    UNSPSC Code

    UNSPSC Code 25172800(Hydraulic systems and components)


    Referencing This Standard
    Link Here
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    DOI: 10.1520/D7721-17

    Citation Format

    ASTM D7721-17, Standard Practice for Determining the Effect of Fluid Selection on Hydraulic System or Component Efficiency, ASTM International, West Conshohocken, PA, 2017, www.astm.org

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