1、Designation: D 6943 03Standard Practice forImmersion Testing of Industrial Protective Coatings1This standard is issued under the fixed designation D 6943; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、 number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice establishes procedures for the evaluationof the resistance of industrial protective coatings to immersionin chemicals.1
3、.2 The values stated in SI units are to be regarded as thestandard. The values given in parenthesis are for informationonly.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 appr
4、o-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 868 Test Method for Chemical Resistance of ProtectiveLiningsD 16 Terminology for Paint, Related Coatings, Materialsand ApplicationsD 610 Test Meth
5、od for Evaluating Degree of Rusting onPaints Steel SurfacesD 714 Test Method for Evaluating Degree of Blistering ofPaintsD 1186 Test Methods for Nondestructive Measurement ofDry Film Thickness of Nonmagnetic Coatings Applied toa Ferrous BaseD 1400 Test Method for Nondestructive Measurement ofDry Fil
6、m Thickness of Nonconductive Coatings Applied toa NonferrousD 2200 Pictorial Surface Preparation Standards for PaintingSteel SurfacesD 3359 Test Methods for Measuring Adhesion by Tape TestD 3363 Test Method for Film Hardness by Pencil TestD 4138 Test Methods for Measurement of Dry Film Thick-ness of
7、 Protective Coatings by Destructive MeansD 4417 Test Methods for Field Measurement of SurfaceProfile of Blast Cleaned SteelD 4541 Test Method for Pull-Off Strength of CoatingsUsing Portable Adhesion TestersD 5162 Practice for Discontinuity (Holiday) Testing ofNonconductive Protective Coating on Meta
8、llic SubstratesD 6132 Test Method for Nondestructive Measurement ofDry Film Thickness of Applied Organic Coatings OverConcrete with an Ultrasonic GageD 6577 Guide for Testing Industrial Protective CoatingsD 6677 Test Method for Evaluating Adhesion by KnifeG 113 Terminology Relating to Natural and Ar
9、tificialWeathering Tests of Nonmetallic MaterialsASTM Manual MNL8 ASTM Manual on MaintenanceCoatings for Nuclear Power Plants2.2 NACE Standard:3TM 0174-2002 Laboratory Methods for the Evaluation ofProtective Coatings and Lining Materials on MetallicSubstrates in Immersion Service2.3 SSPC/NACE Joint
10、Standards:4SSPC-SP5/NACE 1 White Metal Blast CleaningSSPC-SP10/NACE 2 Near White Blast CleaningSSPC-SP13/NACE 6 Surface Preparation of Concrete3. Terminology3.1 The definitions given in Terminologies G 113 and D 16are applicable to this practice.4. Significance and Use4.1 Protective coatings are use
11、d on metallic and concretestorage and processing vessels, shipping containers, dams andrail cars to protect the substrate from corrosive attack and toprotect stored materials (cargo) from contamination. Thismethod provides a means to assess the ability of a protectivecoating to resist degradation by
12、 chemicals and to protect theliquid cargo from contamination by either the substrate orcoating, based on visual observations. Other measures ofdegradation, such as changes in weight or dimensions of thecoating material, or chemical changes to the cargo, may beused to assess this protective ability a
13、s mutually agreed uponbetween contracting parties.1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings, Materials and Applications and is the direct responsibility ofSubcommittee D01.46 on Industrial Protective Coatings.Current edition approved Dec. 1, 2003. Pu
14、blished December 2003.2For 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.3Available from National Association of
15、 Corrosion Engineers (NACE), 1440South Creek Dr., Houston, TX 77084-4906.4Available from The Society for Protective Coatings (SSPC), 40 24th St., 6thFloor, Pittsburgh, PA 15222-4656.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2
16、 This standard practice covers three approaches to con-ducting evaluations of a lining coating materials fitness forpurpose.4.2.1 Method AEvaluation of specimens under conditionsof constant temperature at atmospheric pressure, (that is,without a thermal gradient).4.2.2 Method BEvaluation of specimen
17、s under conditionswhich provide a temperature gradient across the sample: Thetemperature may increase from coated side to uncoated side(Method B1) or decrease from coated side to uncoated side(Method B2).4.2.3 Method CEvaluation of specimens under conditionsof constant temperature and increased pres
18、sure, (that is, with-out a thermal gradient).4.3 Exposure of materials of known performance (a control)at the same time as the test material is recommended.5. Preparation of Test Specimens5.1 Metallic Panels:5.1.1 Use carbon steel panels with a minimum test size of 51by 102 mm (2 by 4 in.), minimum
19、thickness 6.4 mm (18 in.),unless otherwise agreed upon by purchaser and supplier.NOTE 1Test plates with a minimum width of 25 mm (1 in.) may beused if the film thickness is sufficiently uniform to prevent edge effects.5.1.2 Use nominal 4.8 mm (316 in.) thick carbon steel panelsin coating tests if a
20、temperature gradient is included in theimmersion test, unless otherwise agreed upon by purchaser andsupplier.5.1.3 The minimum surface preparation is abrasive blastcleaning to Near-White Metal condition as defined by ASTMD 2200 and by SSPC-SP10/NACE 2. The abrasive and feedpressure shall be selected
21、 to produce an anchor pattern, whichis compatible with the coating system and acceptable to thecoating manufacturer.5.1.4 Unless otherwise specified or agreed upon by pur-chaser and seller, surface preparation shall be “White MetalBlast Cleaning” according to SSPC-SP5/NACE 1, with surfaceprofile of
22、38 to 60 micrometers (1.5 to 3.5 mils) as determinedby Method C of Test Methods D 4417.5.1.5 Other metallic substrates, panel dimensions, or surfacepreparation are acceptable if agreeable to concerned parties.5.2 Concrete and Cementitious Panels:5.2.1 Cementitious PanelsThe minimum panel size is 51b
23、y 102 by 25 mm (2 by 4 by 1 in.). Prepare cementitious panelsby abrasive blast cleaning in accordance with SSPC-SP13/NACE 6 or by other method agreed upon between purchaserand supplier.5.2.2 Concrete BlocksForm, condition and prepare con-crete blocks in accordance with the protocol described inChapt
24、er 6 of the ASTM Manual MNL8. Prepare concreteblocks by abrasive blast cleaning in accordance with SSPC-SP13/NACE 6 or by other method agreed upon betweenpurchaser and supplier.5.3 Coating Application:5.3.1 For panels to be fully immersed, apply the coatingsystem to all test panel surfaces that will
25、 be subjected toexposure.5.3.2 Apply the coating system according to the manufac-turers instructions appropriate for actual or anticipated serviceconditions. Edges should be protected unless the intent of theexperiment is to evaluate the performance of the coating onedges. For coatings to be tested
26、under Method A (immersionwith no temperature gradient) or Method C (immersion at highpressure), apply the candidate coating to the back of the panelin addition to the front and the edges to prevent effects fromdissimilar coatings.5.3.3 Dry film thickness of the coating shall be agreed uponbetween pu
27、rchaser and seller.5.3.3.1 Measure dry film thickness of coating applied toferrous surface in accordance with Test Methods D 1186.5.3.3.2 Measure dry film thickness of coating applied tonon-ferrous metallic surfaces in accordance with Test MethodsD 1400 or D 6132.5.3.3.3 Measure dry film thickness o
28、f linings applied toconcrete or cementitious surfaces in accordance with TestMethod D 6132. Alternatively, measure dry film thickness oflinings applied to concrete or cementitious surfaces by usingsacrificial surfaces prepared concurrently with test specimensin accordance with Test Methods D 4138.5.
29、3.4 Examine the coated surface for holidays in accordancewith Practice D 5162. For test plates and concrete blocks, noholidays are acceptable unless agreed upon between purchaserand seller.6. Sampling6.1 Test chemicals are to be representative of test materialsexpected in actual service.6.2 Prepare
30、at least two test panels or blocks per coatingsystem for each test material.6.3 Prepare at least one test panel or block per coatingsystem to be used as a file specimen (control specimen).6.4 Retain an unused portion of each test medium as ablank.7. Test MethodsNOTE 2This standard describes three me
31、thods for immersion testingof protective coatings and linings. Section 8 provides recommendedexamination methods and intervals between evaluations for the methodsdescribed below.7.1 Method AImmersion with No Temperature Gradient:7.1.1 Test Apparatus:7.1.1.1 A closed vessel constructed of glass or ot
32、her inertmaterial is used with capacity to hold one or more testspecimens with means to relieve pressure if operated atelevated temperatures.NOTE 3Slowly evaporating media may not require a closed vessel.7.1.1.2 Specimens should be positioned so as to avoidspecimen to specimen contact.7.1.1.3 For im
33、mersion at high or low temperature, insula-tion of the vessel is recommended. A separate test vessel isrecommended for each type of coating system being evaluated.For elevated temperature immersion, an apparatus as describedin NACE TM 0174-02, Procedure B, is recommended.7.1.2 Test MediumThe test so
34、lution is selected to corre-spond with the anticipated service of the coating. Add enoughD6943032of the fluid to immerse one half to two thirds of the test panel.The fluid level should be checked at least once every 7 days. Ifmore than 5 % of the test fluid evaporates from the test vessel,add enough
35、 fluid to maintain the level and composition of thefluid.NOTE 4When solvent or water evaporates, ensure that the additionresults in the same concentration as at the start of the test.7.1.3 Test ProcedureMaintain a temperature of 25 6 3C(77 6 5F) unless otherwise indicated by anticipated servicecondi
36、tions or by specification. Ensure that there is a minimumseparation of 25 mm (1 in.) between panels in the vessel.7.2 Method BImmersion with Temperature GradientThe practice defines 2 types of temperature gradients: increas-ing temperature from uncoated to coated side and decreasingtemperature from
37、uncoated to coated side7.2.1 Method B1Temperature gradient with temperatureincreasing from uncoated to coated.7.2.1.1 Test ApparatusA special cylindrical glass test cellis used with multiple necks to provide inlets for thermometer,heater and condenser. The test panel is coated on one side withthe ex
38、terior exposed to the ambient environment. This setupprovides a temperature gradient across the coating.NOTE 5The specific equipment drawings and operation are describedin Test Method C 868 and NACE TM 0174-02, Procedure A.7.2.1.2 Test MediumThe test solution is selected to cor-respond with the anti
39、cipated service of the coating. As this is aclosed system there is no need to replenish the solution duringthe time test specimen is immersed. After disassembly andrating of the panel, fresh medium is normally recommended.7.2.1.3 Test ProcedureClamp the test panels in place atthe ends of the test ce
40、ll with the coating positioned against thecell interior. Fill the test cell to23 to34 of its total height withthe test solution and commence heating.7.2.2 Method B2Temperature gradient with temperaturedecreasing from uncoated to coated.7.2.2.1 Test ApparatusUse a vessel as described in 7.2.1.1but wi
41、th heating element attached to the uncoated exteriorpanel; or install panel with the uncoated side on the hot plateand the chemical container filled with chemical to the coatedside.7.2.2.2 Periodic CyclingUse periodic cycling (heating/cooling) as requested.7.2.2.3 Test MediumThe test solution is sel
42、ected to cor-respond with the anticipated service of the coating. As this is aclosed system there is no need to replenish the solution duringthe time test specimen is immersed. After disassembly andrating of the panel, fresh medium is normally recommended.7.2.2.4 Test ProcedureClamp the test panels
43、in place atthe ends of the test cell with the coating positioned against thecell interior. Fill the test cell to23 to34 of its total height withthe test solution and commence heating.7.3 Method CImmersion Testing at Static Temperatureand Elevated Pressure:7.3.1 Test ApparatusThe test apparatus is an
44、 insulatedautoclave having an external heat source and a capability ofbeing operated at the temperatures and pressures agreed uponby purchaser and supplier.7.3.2 Test ConditionsThe test medium and pressure areselected to correspond with the anticipated service of thecoating.7.3.3 Test Procedure:7.3.
45、3.1 Immerse the test panels completely in the test fluid.7.3.3.2 Using the external heat source, the temperaturewithin the vessel is raised to 43 6 3C (110 6 5F), or asotherwise specified between the purchaser and supplier.7.3.3.3 Raise the pressure of the autoclave to 3 bar (45 psi)or as otherwise
46、specified between the purchaser and supplier.7.3.4 Periodic Cycling:7.3.4.1 To allow initiation of discharging or recharging of avessel, the test panels are removed from the autoclave for atwo-day period once every two weeks. Panels are allowed toreach room temperature at this time.7.3.4.2 Test pane
47、ls are returned to the immersion apparatusafter the cycling ends. The test apparatus is restored to theconditions described in 7.3.3 and 7.3.4.8. Examination and Evaluation8.1 Examination Schedule:8.1.1 For the exposures described in 7.1 (Method A, immer-sion with no temperature gradient) and 7.2 (M
48、ethods B1 andB2, immersion with temperature gradient), the inspectionschedule shall be agreed upon between purchaser and seller.NOTE 6It is suggested to visually inspect the test panels daily for thefirst few days to identify any catastrophic failures, weekly for the firstmonth, and monthly thereaft
49、er.8.1.2 For the exposures described in 7.3 (Method C, immer-sion at elevated temperature and pressures), inspect test panelsat the completion of each cycling period.8.2 Duration of Test:8.2.1 Run the immersion test for a minimum of one month,or other time as agreed to by purchaser and supplier.8.2.2 Alternately run the immersion until a predeterminedlevel of failure is reached. Predefined failure may be based ona purchaser or performance specification or coating manufac-turers internal standards.8.3 Examination Procedures:8.3.1 At all inspections
