1、Designation: C 868 02Standard Test Method forChemical Resistance of Protective Linings1This standard is issued under the fixed designation C 868; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number i
2、n parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers a procedure for evaluating thechemical resistance of a polymer-based protective lining inimmersion service. The method
3、 closely approximates theservice conditions, including the temperature differential be-tween the external and internal surfaces of the equipment,which may accelerate permeation of the lining by a corrosivemedia.1.2 This test may be used to simulate actual field useconditions insofar as a qualitative
4、 evaluation of the liningsystem after a predetermined period of exposure.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.2. Referenced Documents2.1 ASTM Standards:2A 36/A 36M Specification for Carbon Structural SteelA 285/A 285M Specification for Pressure Vessel Plates,Carbon Steel, Low- and Intermediate-Tensile StrengthC 267 Test Methods for Chemical Resistanc
6、e of Mortars,Grouts, and Monolithic Surfacings and Polymer ConcretesD 471 Test Method for Rubber PropertyEffect of LiquidsD 714 Test Method for Evaluating Degree of Blistering ofPaintsD 785 Test Method for Rockwell Hardness of Plastics andElectrical Insulating MaterialsD 1474 Test Methods for Indent
7、ation Hardness of OrganicCoatingsD 2583 Test Method for Indentation Hardness of RigidPlastics by Means of a Barcol ImpressorD 3363 Test Method for Film Hardness by Pencil TestD 4417 Test Methods for Field Measurement of SurfaceProfile of Blast Cleaned SteelD 4541 Test Method for Pull-Off Strength of
8、 CoatingsUsing Portable Adhesion TestersD 5162 Practice for Discontinuity (Holiday) Testing ofNonconductive Protective Coating on Metallic Substrates2.2 NACE Standard:NACE No. 1/SSPC-SP-5 White Metal Blast Cleaning33. Significance and Use3.1 The results obtained by this test method should serve asa
9、guide in, but not as the sole basis for, selection of a liningmaterial for particular application. Simple chemical-resistanceevaluations of the lining materials may be performed moreconveniently by other pertinent methods as a prescreening testfor this procedure in accordance with Test Methods C 267
10、 andD 471.4. Apparatus4.1 Four-Neck Cylindrical, Borosilicate-Type Glass TestCell4, similar to the unit shown in Fig. 1.4.1.1 Where an additional inlet is needed for a thermocoupleor thermistor to control temperature, a five-neck cell should beused.NOTE 1If test solutions that are known to attack gl
11、ass such as HF orcaustic, a fluorocarbon or other suitable cell should be used.4.2 Heating Equipment:4.2.1 The corrosive media may be heated by an electrical-resistant coil fitting inside the test cell. This is protected by aglass immersion tube. The heater shall be controlled throughthe use of a rh
12、eostat or thermostat to produce the desiredtemperature 6 4F (2C).4.2.2 An electrical heating tape may be wrapped around theexterior of the test cell but not around the test panels and maynot touch the test panels.4.3 Reflux Water Condenser, to maintain a constant leveland concentration of the test s
13、olution.1This test method is under the jurisdiction of ASTM Committee C03 onChemical-Resistant Nonmetallic Materials and is the direct responsibility ofSubcommittee C03.03 on Thermoplastic Fabrications.Current edition approved Oct. 10, 2002. Published December 2002. Originallypublished as C 868 77.
14、Last previous edition C 868 85(1995)e1.2For 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 the So
15、ciety for Protective Coatings, 40 24th St., Pittsburgh, PA15222. Web address: http:/www.SSPC.org4The sole source of supply of the four-neck cylindrical, borosilicate-type glasstest cell known to the committee at this time is DelVal Glass Inc., 1135 E. 7th St.,Wilmington, DE. If you are aware of alte
16、rnative suppliers, please provide thisinformation to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee, whichyou may attend.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1942
17、8-2959, United States.4.4 Gaskets, of a chemically resistant material, capable ofwithstanding the chemical environment. The gaskets shall alsoprovide a tight seal between the test cell and test specimen.Gaskets having a Shore “A” Durometer of 60 are generallyadequate. The gasket material shall be se
18、lected so that it doesnot contaminate the test solution.4.5 Air or Gas BubblerIt may be necessary to include anair or gas bubbler to agitate or aerate the solution. Whereaeration is not required, a magnetic stirrer may be used tocreate agitation.4.5.1 At solution temperatures below boiling, agitatio
19、n isrequired to maintain temperature uniformity. Where the servicesolution is considered to be aerated, air should be bubbled intothe solution. In cases where the solution will be air or oxygendepleted, nitrogen or other suitable inert gas should be used foragitation.4.5.2 Insert a bubbler for air o
20、r other gas through the utilityopening in the test cell. The bubbler shall consist of a piece offluorocarbon or glass tubing18 in. (3 mm) in inside diameter,attached to the ground-glass fitting in the utility opening, andextending almost to the bottom of the test cell.4.6 Thermometer or Thermocouple
21、, to fit the prescribedthermowell, capable of registering the temperature specifiedfor the test.4.7 Mounting Equipment (Alternatives):4.7.1 Mount the test panels on the test cell with a minimumof three carbon steel bolts,14 or38 in. (6 or 9 mm) in diameter,using wing nuts for easy removal.4.7.2 “C”
22、clamp fixtures or stainless steel band clamps orother suitable means can be used to mount the test panels to thetest cell.4.7.3 Use clamping pressures sufficient to seal the opening,but not so great as to destroy the test cell or test panel ordamage the test lining.4.8 Cell Test Area:4.8.1 The cells
23、 should be maintained in an open, wellventilated area with temperature controlled to 73 6 4F (23 62C).4.8.2 The preferred method to ensure the free movement ofair past the surfaces is to utilize grills or grating to support thecells with several inches of clearance beneath the grating toallow air fl
24、ow past the plate surfaces. If this type of support isemployed, cells should be at least 6 in. (152 mm) away fromone another or any heat source.4.8.3 If open grating support is not used, cells should be atleast 12 in. (305 mm) from one another or from any potentialsource of heat. They should be plac
25、ed on an open shelf orbench top in such a way that free convective cooling of theunlined side of the test panels may occur.5. Test Specimens5.1 Substrate:5.1.1 Panels shall be commercial quality, unused, hot-rolledcarbon steel (Specifications A 36/A 36M or A 285/A 285M)14by 8 by 8 in. (6 by 200 by 2
26、00 mm).FIG. 1 Four-Neck Cylindrical, Borosilicate-Type Glass Test Cell and AccessoriesC868022NOTE 2With appropriate modification and procedures, this methodcan be used to evaluate linings on other metallic substrates such asstainless steel or other alloys, copper, aluminum, etc., and to evaluatelini
27、ngs on concrete, fiber reinforced plastic (FRP), or other substrates.5.2 Prepare one side of the panels according to the surfaceconditions of NACE No. 1 SSPC-SP-5. The profile depth of thecleaned steel shall be as recommended by the lining manufac-turer. The average profile depth shall be measured b
28、y TestMethods D 4417.5.3 Apply the lining to the test panels as prescribed by themanufacturer and in a manner as closely simulating fieldapplication as possible. For example, if the lining is to be sprayapplied in the field, the lining for the test panels should bespray applied also. Lining thicknes
29、s should be within 10 % ofthe nominal thickness specified.5.3.1 The opposite (unprepared) side should be left unlined.A very thin (1 to 3 mils, 25 to 76 m) coating may be appliedto the unprepared side, if necessary, to prevent rusting.5.3.2 Wherever possible, duplicate test panels should be runto de
30、termine reproducibility of results.5.4 Conditioning of Test PanelsCondition test panels for aperiod of 7 days at 73 6 4F (23 6 2C). Additionalconditioning of test panels, including longer cure times orelevated cure temperatures, may be conducted if specified bythe lining manufacturer.5.5 Specimen Me
31、asurements:5.5.1 Check the thickness of the lining material by using anappropriate dry-film thickness gage.5.5.2 Check the discontinuities in the lining material ofone-side exposure test panels by using Practice D 5162.Consult the lining manufacturer for the recommended voltageto be used. Low voltag
32、e detectors are not recommended unlessspecifically recommended by the lining manufacturer.5.5.2.1 High-voltage holiday detection should not be usedon linings that have been exposed. The test could be destructiveand may not be meaningful since the dielectric strength of thelining material may be chan
33、ged by the exposure.5.5.2.2 If discontinuities are found, either repair the liningor replace the test panel(s).NOTE 3Certain linings are conductive and cannot be tested in thismanner.5.5.3 Visually inspect the lining surface of all panels beforethe test exposure is begun to determine the color, clar
34、ity,surface gloss, and surface texture; also, any gross imperfec-tions such as voids, cracks, runs, or sags.5.5.4 Determine the hardness of the lining by a suitablestandard hardness test such as Test Methods D 785, D 1474,D 2583, and D 3363 in an area of the panel that will not beexposed to the test
35、 solution. Hardness determinations may beinvalid for some aggregate-filled systems.6. Test Solution6.1 The test media shall simulate the anticipated serviceenvironment when testing lining materials for a specificapplication.6.1.1 The concentration(s) of the chemical(s) shall be speci-fied. Unless ot
36、herwise stated, all dilutions shall be made withdistilled, demineralized or deionized water.6.1.2 If no concentration is specified, it is understood thatthe chemical is used in its undiluted form.6.2 Analysis of the test solution may be performed when thefollowing conditions occur:6.2.1 Loss of medi
37、a or buildup of contaminants.6.2.2 Any change of the test solution.7. Procedure7.1 Following the conditioning period, clamp the test panelsin place at the ends of the test cell with the lining materialpositioned against the cell interior. Use a suitable gasketmaterial between the lining and cell fac
38、es described in 4.4 toensure against leakage of the test solution.7.2 The assembled test cell may be filled with tap water andheld approximately1htocheck for complete sealing of theapparatus.7.3 Fill the test cell23 to34 of its total height with the testsolution and commence heating, if required. Ma
39、rk the outer,unexposed panel area, indicating the test solution level forvisual control of the test solution level.7.4 Disassemble the test cell at one month or other intervalsfor inspection. When the apparatus is reassembled, recharge itwith fresh test media. Recharging of the test media may benece
40、ssary at more frequent intervals, if required due to thenature of the media, for instance, NaOCl (see Section 6).7.4.1 When test panels are disassembled from the test cell,rinse the panels with distilled water and wipe dry. No otherconditioning is required.7.5 Interim Evaluation:7.5.1 Make the visua
41、l inspection and record the results forthe following:7.5.1.1 ColorState any changes noted in the color of thelining.7.5.1.2 Surface GlossReport any dulling of the liningsurface.7.5.1.3 Surface TextureNote signs of chemical or physicalerosion.7.5.1.4 BlistersInspect the surface for blisters by visual
42、and audible methods such as lightly tapping or applying astraight edge to the surface of the panel. Describe the size,quantity, and location of blisters. Use Test Method D 714where possible.7.5.1.5 Changes in the test solution.7.6 Final Evaluation:7.6.1 After the sixth month of exposure or upon fail
43、ure,repeat the procedures described in Section 7.5 and conduct thefollowing additional tests:7.6.1.1 Determine the hardness of the lining as described in5.5.4 on portions of the panel exposed to: (1) liquid solution,(2) vapor phase, (3) liquid-vapor interface, and (4) unexposedarea.7.6.1.2 Make an a
44、ppraisal of the adhesion of the lining tothe substrate. Depending on the type of lining, this appraisalmay be made using different methods such as strip peeling,elcometer test (Test Method D 4541) or prying with a knife orsimilar equipment. Not all of these methods will provide aspecific value. Duri
45、ng this destructive evaluation, the locationof blisters should be determined. The blisters may be at theC868023surface of the substrate, between layers within the liningsystem, or within one layer of the lining system.7.6.1.3 High-voltage holiday detection should not be usedon linings that have been
46、 exposed. The test could be destructiveand may not be meaningful since the dielectric strength of thelining material may be changed by the exposure.8. Report8.1 The report shall include the following informationconcerning the lining system and test conditions:8.1.1 Manufacturers name, product design
47、ation, and ge-neric type;8.1.2 Type of test substrate;8.1.3 Method of panel preparation, including the depth ofprofile and all steps and application procedures used in theapplication of the lining. The initial thickness of the lining shallbe measured and recorded;8.1.4 Conditioning procedure;8.1.5 H
48、ardness, visual observations, and note any repairs orany discontinuities. The test method used to determine thehardness shall be noted;8.1.6 Description of lining appearance prior to testing; and8.1.7 Test conditions including test media, temperature,time of exposure, length of intervals between exp
49、osures, andfrequency of recharging test solutions.8.2 The results of each interim inspection shall comprise adescription of the appearance of the test panel at each inspec-tion, noting any changes in the surface texture, evidence ofcracking, blistering, or delamination. Changes in media ap-pearance should be reported.8.3 Qualitative evaluation of the final inspection shall in-clude an appraisal of adhesion of adhesion of the lining to thesubstrate, notation of any signs of substrate attack or corrosionsuch as metal rusting, metal darkening, or any visible o
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