Designation:D4147−99(Reapproved2013)StandardPracticeforApplyingCoilCoatingsUsingTheWire-WoundDrawdownBar1ThisstandardisissuedunderthefixeddesignationD4147;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticecoversaprocedureforapplyingacoatingfilmofuniformthicknessonaflatpanelusingthewire-wounddrawdownbar.1.2Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.SummaryofPractice2.1Aflatpanelissecuredonafirmhorizontalsurface.Anampleamountofcoatingispouredacrossoneendofthepanelandthedrawdownbarplacedbehindthecoating.Thebaristhendrawnwithuniformpressureandspeedalongthelengthofthepaneltowardtheoperatortoapplyauniformfilm.Thewetanddryfilmcoatingthicknessobtainedisdependentonthecombinationofthebarused,thevolumesolidsofthecoating,andthespeedofthedrawdownmotion.3.SignificanceandUse3.1Thispracticeisusefulinthelaboratorytosimulateroll-coatedfilms.4.Apparatus4.1Wire-WoundDrawdownBars—Asetofstainlesssteelwire-wounddrawdownbarsofsufficientdiametertopreventbowingduringapplication.Thesebarsaremanufacturedsothatthediameterofthewirewoundonthebarcontrolsthicknessofthewetfilmapplied.Thechoiceofspecificdrawdownbarisdependentonthedryfilmthicknessrequiredandthevolumesolidsofthecoatingundertest.4.2DevicesforSecuringPanels:4.2.1MagneticChuckforsecuringsteelpanelstoeliminatebowing.4.2.2VacuumPlateforsecuringverylightweightnonmag-neticpanels.4.2.3Tapeforsecuringthetopofthin-gagepanels.4.2.4MechanicalDrives,forsecuringpanelsandautomat-ingthedrawdownprocedure.5.Hazards5.1Theflashpointsofmostsolventsusedincoatingsandrelatedproductsarelowenoughthatadequateventilationisneededtoavoidexce...
