1、Designation:D789913Standard Test Method forMeasuring the Merit of Dispersancy of In-Service EngineOils with Blotter Spot Method1This standard is issued under the fixed designation D7899;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision
2、,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.Scope1.1 This test method covers a procedure for determinationof the merit of dispersancy of diesel crankcase engine oi
3、ls aswell as other types of engine oils where pollutants of diversesources such as soot from combustion,metallic particles fromwear,corrosion of mechanical parts,and insoluble productsresulting from the oxidation of the oil may contaminate thelubricant.1.2 The values stated in SI units are to be reg
4、arded 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
5、the applica-bility of regulatory limitations prior to use.NOTE1It is not the intent of this test method to establish orrecommend normal,cautionary,warning,or alert limits for any machinery.Such limits should be established in conjunction with advice and guidancefrom the machinery manufacturer and ma
6、intenance group.2.Referenced Documents2.1 ASTM Standards:2D7418 Practice for Set-Up and Operation of Fourier Trans-form Infrared(FT-IR)Spectrometers for In-Service OilCondition Monitoring3.Terminology3.1 Definitions:3.1.1 diesel crankcase engine oils,nan engine oil used inthe crankcase of the intern
7、al combustion diesel engine.3.1.1.1 DiscussionIt may contain additives to enhancecertain properties.Inhibition of engine rusting,depositformation,valve train wear,oil oxidation,and foaming areexamples.3.1.2 diesel engine,na reciprocating or rotary engine inwhich ignition of the main fuel charge,as i
8、t is introduced to thecombustion chamber,shall be by the heat of compression of thecharge of combustion air,during regular operation of theengine from idle speeds up to full speed,regardless of whethermiscellaneous methods to augment such heat of compressionare used to facilitate starting of the eng
9、ine under normalconditions or under low ambient temperature conditions or lowintake air temperature conditions.3.1.2.1 DiscussionEngines that are designed to operatewith a continuously hot spot or bulb or other device to facilitateignition or combustion,or both,of low cetane fuels,or anyfuels slow t
10、o ignite or to burn,or both,shall be considered tobe diesel engines for purposes of this test method.3.1.3 engine oil,na liquid that reduces friction or wear,orboth,between the moving parts within an engine;removesheat,particularly from the underside of pistons;and serves asa combustion gas sealant
11、for piston rings.3.1.3.1 DiscussionIt may contain additives to enhancecertain properties.Inhibition of engine rusting,depositformation,valve train wear,oil oxidation,and foaming areexamples.3.1.4 oxidation,nof engine oil,the reaction of the oil withan electron acceptor,generally oxygen,which can pro
12、ducedeleterious acidic or resinous materials often manifested assludge formation,varnish formation,viscosity increase,orcorrosion,or a combination thereof.3.1.5 sludge,nin internal combustion engines,a deposit,principally composed of insoluble resins and oxidation prod-ucts from fuel combustion and
13、the lubricant that does not drainfrom engine parts but can be removed by wiping with a cloth.3.2 Definitions of Terms Specific to This Standard:3.2.1 dispersancythe property that allows oil to suspendand carry away pollutants of diverse sources such as soot fromcombustion,metallic particles from wea
14、r,corrosion of me-chanical parts,and insoluble products resulting from the agingof the oil.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.96.02 on Chemistry for the Evaluation of I
15、n-Service Lubricants.Current edition approved Dec.1,2013.Published January 2014.DOI:10.1520/D7899-13.2For 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 Docume
16、nt Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.Summary of Test Method4.1 A drop of oil is deposited on a piece of specific filterpaper held level and not resting on a surface.The filter paperis placed in an oven set at 80 C for 1 h.The oil wicks acrossthe paper.The oil spot is illuminated with a constant andhomogenous LED(light emitting diodes)backlight.A CCD(charge-coupled device)camera positione
