ASTM_D_3954_-_15.pdf

Designation:D395415Standard Test Method forDropping Point of Waxes1This standard is issued under the fixed designation D3954;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 the determination of the ASTMdropping point for waxes.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:2D566 Test Method for Dropping Point of Lubricating Grease3.Summary of Test Method3.1 In this test method,the dropping point is defined as thetemperature at which the wax suspended in a cylindrical cup,with a 2.8-mm diameter hole in the bottom,flows downward adistance of 19 mm to interrupt a light beam as the sample isheated at a constant rate in air.4.Significance and Use4.1 Waxes do not go through a sharp solid-liquid phasechange when heated and therefore do not have a true meltingpoint.As the temperature rises,waxes gradually soften orbecome less viscous.For this reason,the determination of thesoftening point must be made by an arbitrary but closelydefined method if test values are to be reproducible.4.2 This test is useful in determining the consistency ofwaxes,and as one element in establishing the uniformity ofshipments or source of supply.4.3 This test method has been found suitable for all types ofwaxes including paraffin,microcrystalline polyethylene,andnatural waxes.5.Apparatus5.1 Suitable apparatus that meets the requirements of 5.1.1,5.1.2,and 5.1.3 can be used to determine dropping points bythis test method.Instruments are available commercially3consisting of a control unit with a digital temperature recorder,matched furnace,sample cartridges,and accessories.Thecontrol unit automatically maintains the furnace temperatureand controls the heating rate with a precision of 0.1C.Thedropping point is automatically recorded,and the furnaceheating program is turned off when the sample interrupts thelight beam and triggers the photocell detector.5.1.1 Control UnitThis unit shall provide a continuouslinear temperature control from 25 to 250C at a 2C/min rate.A digital readout shall record the softening point with anaccuracy of 0.1C.5.1.2 Furnace UnitThis unit shall be capable of heating asample cup assembly as described in 5.1.3 at 2C 6 0.3C/minlinear rate from 25 to 250C.It shall include a sensing systemcapable of detecting the softening point with an accuracy of0.1C.5.1.3 Sample Cup AssemblyA chromium-plated brass cupconforming to the dimensions shown in Test Method D566.Itshall be placed in an assembly so that the sample flows downa distance of 19 mm to interrupt a light beam to cause digitaldisplay of the softening point.6.Preparation of Sample6.1 For waxes heat the sample to 15 to 20C above itsmelting point to form a pourable liquid.Place the sample cupson glass slides and pour the melted sample into the cup to alevel even with the upper rim of the cup.Allow the sample tostand at room temperature for 2 h before running.1This test method is under the jurisdiction ofASTM Committee D21 on Polishesand is the direct responsibility of Subcommittee D21.02 on Raw MaterialsCurrent edition approved Oct.1,2015.Published October 2015.Originallyapproved in 1980.Last previous edition approved in 2010 as D3954 94(2010).DOI:10.1520/D3954-15.2For 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.3To the knowledge of the committee at this time,the only instruments whichsatisfy the requirements of 5.1.1,5.1.2,and 5.1.3 are Mettler-Toledo model DP70and model DP90 fitted with FP83HT sample cup.These are available fromMettler-Toledo,LLC,1900 Polaris Parkway,Columbus,OH 43240,.If you are aware of alternative suppliers,please provide this information to ASTMInternational Headquarters.Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 7.Preparation of Apparatus7.1 Ensure that the furnace unit and the sample cup assem-bly are clean and bright,since tarnished or dirty apparatus willchange the apparent dropping point.After each determination,check to see if the apparatus requires cleaning.NOTE1It is advisable to keep the equipment covered