1、Designation: F2329 13Standard Specification forZinc Coating, Hot-Dip, Requirements for Application toCarbon and Alloy Steel Bolts, Screws, Washers, Nuts, andSpecial Threaded Fasteners1This standard is issued under the fixed designation F2329; the number immediately following the designation indicate
2、s 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. Scope*1.1 This specification covers the requirements fo
3、r hot-dipzinc coating applied to carbon steel and alloy steel bolts,screws, washers, nuts, and special threaded fasteners. It alsoprovides for minor coating repairs. Nails and rivets are notincluded in this specification.1.2 It is intended to be applicable to fasteners that arecentrifuged or otherwi
4、se handled to remove excess galvanizingbath metal (free zinc).1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combining
5、values from the two systems may result in non-conformancewith the standard.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 determin
6、e the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A153/A153M Specification for Zinc Coating (Hot-Dip) onIron and Steel HardwareA563 Specification for Carbon and Alloy Steel NutsA563M Specification for Carbon and Alloy Steel Nuts (Met-ric)A780 Prac
7、tice for Repair of Damaged and Uncoated Areasof Hot-Dip Galvanized CoatingsB487 Test Method for Measurement of Metal and OxideCoating Thickness by Microscopical Examination ofCross SectionE376 Practice for Measuring Coating Thickness byMagnetic-Field or Eddy-Current (Electromagnetic) Test-ing Method
8、sF606 Test Methods for Determining the Mechanical Proper-ties of Externally and Internally Threaded Fasteners,Washers, Direct Tension Indicators, and RivetsF606M Test Methods for Determining the Mechanical Prop-erties of Externally and Internally Threaded Fasteners,Washers, and Rivets (Metric)F1470
9、Practice for Fastener Sampling for Specified Me-chanical Properties and Performance InspectionF1789 Terminology for F16 Mechanical Fasteners3. Terminology3.1 Definitions:3.1.1 Terms used in this specification are defined in Termi-nology F1789 unless otherwise defined in this specification.3.1.2 batc
10、h lotquantity of identical parts cleaned, pickled,fluxed, and galvanized together at one time in a galvanizingbasket.3.1.3 galvanizinghot-dip zinc coating.3.1.4 high temperature galvanizinggalvanizing processcarried out in a ceramic vessel (kettle) at an approximatetemperature ranging between 990F a
11、nd 1040F 530C and560C.3.1.5 hot-dip zinc coating of mechanical fastenersprocesswhereby fasteners are zinc coated by immersion in a bath ofmolten zinc, resulting in the formation of the iron/zinc alloycoating and a zinc coating at the surface of the fastener. Thisprocess involves the removal of exces
12、s zinc by spinning theparts in a centrifuge, or brushing the threaded portion, orhandling otherwise to remove the excess zinc.3.1.6 production lotbatches of parts originating from thesame manufacturing lot, processed continuously throughcleaning, pickling, fluxing, dipping in molten zinc and spun in
13、1This specification is under the jurisdiction of ASTM Committee F16 onFasteners and is the direct responsibility of Subcommittee F16.03 on Coatings onFasteners.Current edition approved June 1, 2013. Published June 2013. Originallyapproved in 2005. Last previous edition approved in 2011 as F2329-11.
14、DOI:10.1520/F2329-13.2For 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.*A Summary of Changes section appears at
15、 the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1a centrifuge, or other means, without any significant change intime, temperature, and concentration of the constituents of theprocess.3.1.7 stress reliefprocess
16、of heating parts for a definitetime at a given temperature in order to relieve stress induced bywork hardening.4. Ordering Information4.1 Orders for zinc coating of fasteners to this specificationshall include the following:4.1.1 Name of product (that is bolt, stud, nut, washers, orother);4.1.2 ASTM
17、 designation and year of issue, including fas-tener specification number;4.1.3 Hydrogen embrittlement relief treatment, as requiredby the purchaser (see, 7.2.3);4.1.4 Quantity of fasteners to be hot-dip zinc coated;4.1.5 Stress relief or tempering temperature to which thefasteners where subjected, i
18、f applicable;4.1.6 Secondary processing such as chromating,phosphating, or lubrication, if applicable;4.1.7 Average galvanizing temperature to which fastenerswill be subjected, if required by the purchaser (see 7.2.2);4.1.8 Specify baking if required (see 7.2.3); and4.1.9 Certification, if required
19、(see 14.1).5. Materials and Manufacture5.1 Condition of the As-Received FastenersThe fastenersas received by the galvanizer shall be free from contaminantsthat are not readily removed in the cleaning process and wouldadversely affect the galvanizing.5.2 ProcessUnless otherwise covered in this specif
20、ication,all processing parameters shall be in accordance with therequirements of Specification A153/A153M.5.2.1 Process ControlGalvanized fasteners subjected to aprocess control plan based upon batch lot level shall complywith the batch lot sampling plan in Table 1, and the samplingplan for producti
21、on lot (prevention process) as determined in10.2.2 shall be applied.5.3 Spinning and Quenching:5.3.1 Parts shall be spun immediately following removalfrom the galvanizing bath and quenched in water. In addition,small parts shall be air cooled, as needed, in order to preventthe formation of zinc oxid
22、e.5.3.2 Parts, which cannot be spun shall be brushed orhandled otherwise to remove the excess zinc.5.4 Alteration of Threaded Fasteners:5.4.1 Fasteners that have been hot-dip galvanized shall notbe further altered (such as subjected to a cutting, rolling, orfinishing-tool operation) by the galvanize
23、r unless specificallyauthorized in writing by the purchaser.5.4.2 Hot-dip galvanizing of externally threaded fastenersshall meet the thread fitting requirements of the specifiedproduct standard or specific allowance as determined by thecustomer.NOTE 1The scope of this specification does not cover th
24、e require-ments regarding the overtapping of galvanized nuts. These requirementsare established by the applicable product standard, such as SpecificationA563, Specification A563M (or others), or in writing by the purchaser, ifneeded.5.5 Secondary Processing:5.5.1 When requested by the purchaser, tre
25、atments such aschromating or phosphating shall be applied to reduce thepossibility of wet storage staining (white corrosion) or to assistsubsequent painting.5.5.2 When specified on the purchase order, the nuts, bolts,or screws shall be lubricated to enhance assembly.5.6 Touch-up and RepairBare, cut,
26、 or damaged spotsfound on fasteners after galvanizing, totaling less than 1% ofthe coated surface area, may be repaired with paints containingzinc dust. Such paints shall have zinc-dust concentrations of 65to 69% or concentrations above 92% in the dried film. Therepairing party shall select the pain
27、t and follow its applicationinstructions. The applied coating shall provide barrierprotection, and preferably be anodic to steel. Thickness mea-surements of repaired areas shall not be required.NOTE 2Experience shows that, in general, organic zinc-rich systemsare tolerant of marginal surface prepara
28、tion and are not critical ofclimactic or atmospheric conditions for curing. Corrosion resistance andservice performance are very dependent on the properties of the paintsystem, the extent of surface preparation, and the skills of individualapplicators. See Practice A780.6. Chemical Composition of Zi
29、nc6.1 Unless otherwise specified in the product standard, thezinc used for the coating shall conform to the requirements ofthe section on Zinc of Specification A153/A153M.7. Safeguards Against Alteration of Fasteners MechanicalProperties7.1 Stress ReliefFasteners subjected to severe work hard-ening
30、shall be stress-relieved by the fastener manufacturerprior to hot-dip zinc coating (galvanizing).7.2 Hot-Dip Zinc Coating:7.2.1 Effect of Temperature on Mechanical Properties:7.2.1.1 Galvanizing carried out at a temperature above800F 425C can adversely affect the final mechanicalproperties of the fa
31、steners. Therefore, the supplier of thefasteners submitting the product to the galvanizer shall beaware of the tempering temperature of the fasteners relative toTABLE 1 Process Control of Batch LotASampling PlanSample SizeBBatch Lot Size Average CoatingThicknessCAdhesion AppearanceD5to25 1 1 126 to
32、50 1 1 251 to 150 2 1 2151 and over 2 2 2AThe acceptance criterion in all cases is zero defects.BThe sample size is the number of specimen(s) required to be tested/inspected tothe applicable criteria.CFrequency of coating thickness measurements: one set of specimen(s) for everyfive batch lots. For t
33、est method, see 11.1.DVisual inspection for conformance.F2329 132the temperature of the galvanizing bath and the potential effectit may have on the product. When requested by the purchaser,the average galvanizing temperature that the fasteners will besubjected to shall be furnished.7.2.1.2 Unless ot
34、herwise required by the product standard orby the purchaser, testing for mechanical properties is notnecessary if the galvanizing process is carried out at a lowertemperature than the stress relief or tempering temperature ofthe fasteners. If the galvanizing process is carried out at ahigher tempera
35、ture than the stress relief or the temperingtemperature of the fasteners, than the purchaser shall makeprovision for mechanical testing.7.2.1.3 Threaded fasteners made from carbon or alloy steelheat treated to a minimum specified hardness of 40 HRC, orcase hardened steel fasteners shall not be hot-d
36、ip zinc coated.7.2.2 Effect of Hydrogen on the Mechanical Properties afterGalvanizingHydrogen has the potential of being introducedinto the steel during acid pickling, prior to hot-dip galvanizing.For high strength fasteners (having a specified minimumproduct hardness of 33 HRC), there is a risk of
37、internalhydrogen embrittlement. If required by the product standard orby the purchaser, mechanical descaling (with or without flashpickling) or baking shall be conducted to reduce the risk ofinternal hydrogen embrittlement. Baking shall be conductedafter pickling and prior to hot-dip galvanizing.7.2
38、.3 Effect of the Galvanizing TemperatureExternallythreaded ferrous fasteners over 1.00 in. M24 diameter with aspecified minimum hardness of HRC 33 and higher shall not behot-dip zinc coated at high temperature (see definition in 3.1.4)in order to avoid microcracks.8. Coating and Dimensional Requirem
39、ents8.1 Coating ThicknessThe zinc coating thickness shallmeet the requirements of Table 2.8.2 DimensionThe dimensional characteristics of the fas-teners shall be in accordance with the requirements of thepurchaser, when specified in the order. The purchaser shallensure that the effect of the heat ge
40、nerated by the galvanizingprocess is compatible with the fastener regarding the finaldimensional characteristics of the parts. Furthermore, thegalvanizer shall not be held responsible for any unanticipateddistortion of parts. In addition, the purchaser shall providefasteners having sufficient dimens
41、ional allowance to accom-modate the zinc thickness deposition, as required in 8.1.8.3 Adhesion of Zinc CoatingThe zinc coating shall ad-here tenaciously to the surface of the base metal. The methodfor testing the condition of adherence is specified in 11.5.9. Workmanship, Finish, and Appearance9.1 A
42、ppearance of Zinc Coating:9.1.1 After hot-dip galvanizing, the fasteners shall meet therequirements of the section on Workmanship, Finish, andAppearance of Specification A153/A153M. Galvanized wash-ers shall not be bonded to each other (See Note 3). Parts maybe dull due to the presence of silicon in
43、 the steel. The dullappearance shall not be cause for rejection.NOTE 3Hot-dip washers tend to bond to each other. Suitable accep-tance criteria shall be agreed between the purchaser and the galvanizerbefore placing the order. Unless otherwise agreed to in the purchase order,delivered galvanized wash
44、ers shall not be bonded to each other.9.1.2 The test method shall be in accordance with 11.3.9.2 Smoothness of Zinc Coating:9.2.1 The zinc coating shall be smooth and reasonablyuniform in thickness, as defined in the section onWorkmanship, Finish, and Appearance of Specification A153/A153M. Smoothne
45、ss of a surface is a relative term. Minorroughness that does not impair the intended use of the part, orroughness that is related to the uncoated surface condition ofthe part, shall not constitute grounds for rejection of the parts.9.2.2 The test method shall be in accordance with 11.3.10. Sampling1
46、0.1 Test specimens shall be selected at random from eachproduction lot or batch lot, when applicable.10.2 Selection of the Sampling PlanProduction LotTwosampling plans are proposed, one based on detection processand one based on prevention process as defined in TerminologyF1789. The selection of the
47、 sampling plan shall be in accor-dance with Guide F1470.TABLE 2 Zinc Coating ThicknessMinimum Thickness on SurfaceDimensionA,BAverage Thickness of AllSpecimens Tested(Production Lot)C,BAverage Thickness of AllSpecimens Tested(Batch Lot)D,BAverage Thickness ofIndividual SpecimenBFasteners and nuts ov
48、er38 in. M10 in diameterWashers316 in. 4.7 mm and over in thickness0.0020 in. 50 m 0.0017 in. 43 m 0.0017 in. 43 mFasteners and nuts38 in. M10 and under in diameterWashers under316 in. 4.7 mm in thickness0.0017 in. 43 m 0.0015 in. 38 m 0.0015 in. 38 mAIn the case of long pieces, such as anchor rods
49、and similar articles over 5 ft 1.5 m in length, the thickness measurement shall be determined at each end and the middleof the article. In the case of a fully threaded rod, the thickness measurements shall be determined at each end of the article. In no case shall the averageofthemeasurements be below the average thickness shown in the Average Thickness on Individual Specimen column (see 11.2). The number of specimens to be tested perorder shall be as specified in Section 10. NoteBased upon mathematical calculations, 1.
