ASTM_D_7933_-_22.pdf

Designation:D793322Standard Test Method forEngine Coolant Stagnation in Flux-Brazed Aluminum HeatExchangers1This standard is issued under the fixed designation D7933;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.Scope1.1 This test method covers a laboratory screening proce-dure for evaluating engine coolant compatibility and corrosionprotection after aging two weeks at 90 C in an aluminum heatexchanger brazed using flux.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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1176 Practice for Sampling and Preparing Aqueous Solu-tions of Engine Coolants orAntirusts for Testing PurposesD1193 Specification for Reagent WaterD4340 Test Method for Corrosion of Cast Aluminum Alloysin Engine Coolants Under Heat-Rejecting ConditionsE230/E230M Specification for Temperature-ElectromotiveForce(emf)Tables for Standardized Thermocouples3.Summary of Test Method3.1 An aluminum heat exchanger that was brazed using fluxvia any application method or as part of the material claddingis filled with engine coolant,plugged,and placed in an oven fortwo weeks(336 h)at 90 C.Engine coolant compatibility isassessed based on changes in coolant physical and composi-tional properties,and engine coolant aluminum corrosionprotection is based on performance in the Test Method D4340test.4.Significance and Use4.1 Automobile and truck radiators and heater cores are nowpredominantly made with aluminum alloys using variousmanufacturing processes including brazing with a flux(SeeAppendix X1 for additional information).The presence ofresidual internal brazing flux in heat exchangers along with thehigh ratio of internal aluminum surface area to coolant volumemay affect certain physical and chemical properties and corro-sion protection of the coolant.This test method provides ascreening test to assess engine coolant physical and chemicalproperties and corrosion protection after aging it in a heatexchanger brazed with flux at elevated temperature understagnant conditions.This method cannot stand alone as evi-dence of satisfactory coolant performance in flux-brazed alu-minum heat exchangers.The actual service of an enginecoolant formulation can be determined only by more compre-hensive bench,dynamometer,and field tests.5.Apparatus5.1 Aluminum Heat Exchanger Brazed with FluxThe heatexchanger may be a radiator,heater core,or other,liquidcooled heat exchanger.NOTE1The aluminum brazed heat exchangers used in this testmethod may be commercially produced or experimentally prepared by theheat exchanger supplier.The aluminum grade,alloying,flux loadingduring brazing,and residual flux remaining in the heat exchanger afterbrazing may vary from part to part.The heat exchanger type,manufacturer,size,and other design parameters are decided by mutualagreement of the parties involved.5.2 Coolant Hoses,Clamps,Hose Adapters,and Caps orPlugsRubber engine coolant hoses(approximately 15 cmlength)of appropriate diameter shall be fitted onto heatexchanger inlet/outlets to allow for coolant expansion.EPDMis one type hose material suitable for the test.Metal clamps,hose adapters,and threaded caps or plugs(stainless steel,orsteel)shall be used to seal the heat exchanger during the1This test method is under the jurisdiction of ASTM Committee D15 on EngineCoolants and Related Fluids and is the direct responsibility of SubcommitteeD15.21 on Extended Life Coolants.Current edition approved June 1,2022.Published June 2022.Originallyapproved in 2015.Last previous edition approved in 2015 as D793315.DOI:10.1520/D7933-22.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopme