ASTM_D_4871_-_11.pdf

Designation:D487111Standard Guide forUniversal Oxidation/Thermal Stability Test Apparatus1This standard is issued under the fixed designation D4871;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This guide covers an apparatus used to measure theoxidation or thermal stability of liquids by subjecting them totemperatures in the range from 50 to 375C in the presence ofair,oxygen,nitrogen,or other gases at flow rates of 1.5 to13 L h,or in the absence of gas flow.Stability may bemeasured in the presence or absence of water or soluble orinsoluble catalysts.Gases evolved may be allowed to escape,condensed and collected,or condensed and returned to the testcell.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D91 Test Method for Precipitation Number of LubricatingOilsD156 Test Method for Saybolt Color of Petroleum Products(Saybolt Chromometer Method)D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids(and Calculation of Dynamic Viscos-ity)D664 Test Method for Acid Number of Petroleum Productsby Potentiometric TitrationD974 Test Method for Acid and Base Number by Color-Indicator TitrationD1500 Test Method for ASTM Color of Petroleum Products(ASTM Color Scale)D3339 Test Method forAcid Number of Petroleum Productsby Semi-Micro Color Indicator TitrationD5763 Test Method for Oxidation and Thermal StabilityCharacteristics of Gear Oils Using Universal GlasswareD5770 Test Method for Semiquantitative Micro Determina-tion of Acid Number of Lubricating Oils During Oxida-tion TestingD5846 Test Method for Universal Oxidation Test for Hy-draulic and Turbine Oils Using the Universal OxidationTest ApparatusD6514 Test Method for High Temperature Universal Oxida-tion Test for Turbine Oils3.Summary of Guide3.1 An apparatus is described in which a sample of testfluid,typically from 100 ml or 100 g,is subjected to thermal oroxidative degradation or both.Insoluble or soluble catalystmay be added.Gas may be bubbled through the liquid toprovide agitation or to promote oxidation or both.Water orwater vapor may be added.At the end of the test or at intervalsthroughout the test,the liquid is monitored for change inneutralization number,viscosity,weight loss,formation ofsludge,or for other parameters.The corrosivity of the fluidtoward any catalyst metals can be determined from theappearance and weight change of the metal test specimens,ifpresent,or by monitoring the oil and any sludge or water formetal content.The test is terminated after a fixed time periodor when a selected parameter reaches a condemning value.NOTE1The volume of liquid at test temperature should be sufficientto cover the catalysts and should not extend beyond the heated portion ofthe bath.4.Significance and Use4.1 This standard describes an apparatus that provides theversatility required to conduct oxidation or thermal stabilitytests on liquids using a wide variety of test conditions.It issufficiently flexible so that new test conditions can be chosen inresponse to the changing demands of the marketplace.4.2 Procedures using this apparatus are described in thefollowing ASTM standard test methods:D5763,D5846,andD6514.Other procedures may be in use,but they have not beendeveloped as ASTM standard test methods.1This guide is under the jurisdiction of ASTM Committee D02 on PetroleumProducts,Liquid Fuels,and Lubricants and is the direct responsibility of Subcom-mittee D02.09.0D on Oxidation of Lubricants.Current edition approved Dec.1,2011.Published January 2012.Originallyapproved in 1988.Last previous edition approved in 2006 as D487106.DOI:10.1520/D4871-11.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Apparatus5.1 Heating Block,as shown at the lower right in Fig.1,toprovide a controlled constant temperature for conducting tests.5.1.1 Test cells are maintained at constant elevated tempera-ture by means of a heated aluminum block which surroundseach test cell.5.1.2 Holes in the aluminum block to accommodate the testcells shall provide 1.0 mm max clearance f