ASTM D7752-2018 pdf free download

ASTM D7752-2018 pdf free download.Standard Practice for Evaluating Compatibility of Mixtures of Hydraulic Fluids
1. Scope
1.1 This practice covers the compatibility of mixtures of hydraulic fluids as defined by Specifications D6158, DIN 51524, ISO 11158, and ISO 15380. 1.2 This practice can be used to evaluate new (unused) lubricant compatibility or the effects of combining new (re- placement) lubricant with in-service (original) lubricant in the system. 1.3 To evaluate primary compatibility using this method, the replacement fluid must pass the ISO 13357-1 Stage II filter- ability test. The original fluid is not required to pass ISO 13357-1 filterability test, Stage I or II. 1.4 Primary testing is conducted on fluid mixtures in 2:98, 10:90, and 50:50 ratios using the ISO 13357-1 Filterability Test, Stage II. 1.5 Secondary testing is suggested when circumstances indicate the need for additional testing. 1.6 This practice does not evaluate the wear prevention characteristics, load carrying capacity, or the mechanical shear stability of lubricant mixtures while in service. If anti-wear (AW), extreme pressure (EP), or shear stability are to be evaluated, further testing of these parameters may be required. 1.7 This practice does not purport to cover all test methods that could be employed. 1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.9 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 appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.10 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
3. Terminology
3.1 Definitions ofTerms Specific to This Standard: 3.1.1 2:98 mixture, n—a uniform blend of 2 % by weight of original fluid with 98 % by weight of replacement fluid. 3.1.2 10:90 mixture, n—a uniform blend of 10 % by weight of original fluid with 90 % by weight of replacement fluid. 3.1.3 50:50 mixture, n—a uniform blend of 50 % by weight of each of two component fluids. 3.1.4 compatibility, n—of hydraulic fluids, the ability of hydraulic fluids to mix together without significant degradation of properties or performance. 3.1.4.1 Discussion—Compatibility will be determined using the ISO 13357-1 filterability test. When a mixture passes the Stage II filterability designation as specified in the ISO 13357-1 test, the mixture is considered compatible at the tested ratio by the primary testing procedure. If this practice is to be used for adding new (replacement) to in-service (original) and the system is not drained (for example, top-up), two additional ratios will be required, 10:90 and 2:98. Depending on the ratios that have passed the test, flush quantities are given in Annex A1. 3.1.5 fail, n—in secondary compatibility testing ofhydraulic fluid mixtures, a test result that is inferior to that of the poorer of the two constituent fluids. 3.1.6 original fluid, n—fluid that the system is being con- verted from. 3.1.7 pass, n—in secondary compatibility testing ofhydrau- lic fluid mixtures, a test result that is equal to or better than that of the poorer of the two constituent fluids. 3.1.8 primary testing, n—Two constituent fluids are com- bined at 2:98, 10:90, and 50:50 ratios by weight. The fluid mixtures are prepared, aged, and evaluated for changes in filterability using the procedure described in ISO 13357-1. 3.1.9 replacement fluid, n—fluid that the system is being converted to. 3.1.10 secondary testing, n—Mixtures of the fluids are prepared following ISO 13357-1 samples and sampling section and evaluated for changes in the parameters detailed in 7.4.