1、Designation:A896/A896M09(Reapproved 2014)Standard Practice forConducting Case Studies on Galvanized Structures1This standard is issued under the fixed designation A896/A896M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of
2、 last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice sets forth the procedures for conductingcase studies of galvanized installations.It is intended forstructur
3、al members and other permanent parts of theinstallation,such as railings and other such fabrications.1.2 Included in this practice are recommendations for thevisual inspection of the galvanized structure,measurement ofcoating thickness,and reporting of results.1.3 This specification is applicable to
4、 orders in eitherinch-pound units(as A896)or in SI units(as A896M).Inch-pound units and SI units are not necessarily exactequivalents.Within the text of this specification and whereappropriate,SI units are shown in brackets.Each system shallbe used independently of the other without combining values
5、 inany way.1.4 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.Refer
6、enced Documents2.1 ASTM Standards:2B499 Test Method for Measurement of Coating Thicknessesby the Magnetic Method:Nonmagnetic Coatings onMagnetic Basis MetalsE376 Practice for Measuring Coating Thickness byMagnetic-Field or Eddy-Current(Electromagnetic)Test-ing Methods3.Significance and Use3.1 This p
7、ractice is applicable to galvanized structuresexposed to the atmosphere or to plant environments,includingbuildings,bridges,and industrial plant constructions.3.2 It provides for the collection of data to document theprotection afforded by the galvanized coating.3.3 Method A for conducting a coating
8、 thickness surveyaims essentially at an assessment of the general condition ofthe galvanized structure,at the time of the inspection,by takingthickness measurements on several members of the structure.3.4 Method B provides for accurate monitoring of thecoating thickness decrease as a function of tim
9、e,at specificlocations on the structure,in order to assess the corrosivity ofthe environment,the effect of orientation,elevation,or otherfactors.3.5 Method B is not an alternate procedure to MethodA,butis complementary and optional.4.Apparatus4.1 Surface Preparation:4.1.1 Water.4.1.2 Cloths,for wash
10、ing and drying.4.1.3 Soft Fiber Bristle Brush.4.2 Coating Thickness Measurement:4.2.1 Thickness Gage.4.2.2 Steel Calibration Plates and Foils.4.2.3 Permanent Marker.4.2.4 Tape Measure.4.2.5 Center Punch.4.2.6 Hammer.4.3 Electronic Magnetic Flux Gage The use of an elec-tronic magnetic-flux gage in ac
11、cordance with Method B499 isrecommended.Instruments with an accuracy of 63 to 65%are commercially available.4.3.1 Probes having a constant pressure feature will mini-mize operator error.4.3.2 The probe assembly should have a probe support ifmeasurements are to be made on rounded or curved surfaces.4
12、.4 Hand-Held Magnetic GageA hand-held magneticgage using the magnetic attraction principle in accordance withPractice E376 may be used for Method A.5.General Procedure5.1 Background Information:5.1.1 Wherever possible,obtain information on the tonnageand cost of the steel work,the cost of galvanizin
13、g,and1This practice is under the jurisdiction of ASTM Committee A05 on Metallic-Coated Iron and Steel Productsand is the direct responsibility of SubcommitteeA05.13 on Structural Shapes and Hardware Specifications.Current edition approved May 1,2014.Published May 2014.Originallyapproved in 1989.Last
14、 previous edition approved in 2009 as A896/A896M-09.DOI:10.1520/A0896_A0896M-09R14.2For 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 on
15、the ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 estimates of alternative coating costs(initial and maintenance)if the steelwork had been coated by another method.Determineif there are areas of the installation which were
16、painted ratherthan galvanized,or painted over galvanizing.5.1.2 Determine if any problems were experienced duringfabrication,galvanizing,construction,and operation.5.2 Corrosive Environment Identification:5.2.1 The galvanized installation should be divided accord-ing to the various corrosive environments to which it isexposed.For example,plant atmospheres could be categorizedwith respect to the processing step.Sheltered versus boldlyexposed areas can be considered as two different environments.5
