1、Designation: D7127 05D7127 13Standard Test Method forMeasurement of Surface Roughness of Abrasive BlastCleaned Metal Surfaces Using a Portable Stylus Instrument1This standard is issued under the fixed designation D7127; the number immediately following the designation indicates the year oforiginal a
2、doption 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. Scope1.1 This test method describes a shop or field procedure for determinatio
3、n of four roughness characteristics of surfaces preparedfor painting by abrasive blasting. The procedure uses a portable skidded or non-skidded stylus profile tracing instrument. The threemeasured characteristics are: Rt and Rpc. Additional measures of profile height (Rmax and/or Rz) may also be obt
4、ained as agreedupon by purchaser and seller. (The digitally-determined profile parameters Rt,Rmax,Ry and Pc.Rzlmax are extremely similar indefinition.)1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 In general, this m
5、ethod should be limited to the measurement of surface roughness where RmaxRt is in the range 10 to 150m (0.4 to 6 mil) and where the Peak Count, Pc,Rpc is less than 180 peaks/cm (450 peaks/in.).1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use.
6、 It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D4417 Test Methods for Field Measurement of Surface Profile of Blast Cleaned Ste
7、elE177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method2.2 ASME Standard:ASME B46.1-2002 Surface Texture, Surface Roughness Waviness and Lay32.3 ISO Standards:ISO 4287: 1997 Geometri
8、cal Product Specifications (GPS)Surface Texture: Profile MethodTerms, Definitions, and SurfaceParameters43. Terminology3.1 DefinitionsThe following definitions are provided as an aid to users of this document. Formal definitions of the surfaceroughness and instrument parameters below are contained i
9、n the referenced standards.standards (Fig. 1).3.1.1 deadband, nthat distance above and below the mean line that a continuous trace line must cross in both directions (upand down) to count as a single peak.3.1.1.1 Discussion1 This test method is under the jurisdiction of ASTM Committee D01 on Paint a
10、nd Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.46 on Industrial Protective Coatings.Current edition approved Dec. 1, 2005Feb. 1, 2013. Published January 2006May 2013. Originally approved in 2005. Last previous edition approved in 2005 as D7127 05
11、. DOI: 10.1520/D7127-05.10.1520/D7127-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from Ame
12、rican Society of Mechanical Engineers (ASME), ASME International Headquarters, Three Park Ave., New York, NY 10016-5990.10016-5990,http:/www.asme.org.4 Available from International Organization for Standardization (ISO), 1 rue de Varemb, Case postale 56, CH-1211, Geneva 20, Switzerland. 1, ch. de la
13、 Voie-Creuse,CP 56, CH-1211 Geneva 20, Switzerland, http:/www.iso.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depic
14、t all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1942
15、8-2959. United States1Use of a deadband diminishes the effect of small, spurious peaks due to noise.3.1.2 evaluation length, na sequence of five consecutive sampling lengths.3.1.3 Pc,Rpc, nthe number of peak/valley pairs, per unit of length, extending outside a “deadband” centered on the mean line.3
16、.1.4 Rt, nthe vertical distance between the highest peak and lowest valley within any given evaluation length.3.1.5 Rmax, nthe largest peak to valley measurement is determined from greatest vertical distance between highest peak andlowest valley for any of the five sampling lengths, and the largest
17、of these five values is lengths that comprise an evaluationlength.Rmax.3.1.6 Rt,Rz, nthe vertical distance between the highest peak and the lowest valley within any given lowest valley in a samplinglength averaged over the five sampling lengths comprising the evaluation length.3.1.7 sampling length,
18、 nthe nominal interval distance parallel to the surface being assessed within which a single value of asurface parameter is determined.3.1.8 surface preparation, nthe cleaning and profiling of a metallic surface using an abrasive blast media or mechanical meansto prepare that surface for coating.3.1
19、.9 surface profile, nfor purposes of the standard, the positive and negative vertical deviations (peaks and valleys) aremeasured from a mean line approximately the center of the profile being evaluated.Top Illustration of stylus device terminology: sampling length,evaluation length, traverse length.
20、Bottom Expanded view of a single sampling length to illustratesurface structure terminology:Rt: difference between highest peak and lowest valley over theevaluation length.Rmax: difference between highest peak and lowest valley over thesampling. lengthPc: number of peak/valley pairs, per unit length
21、 extending outsidea deadband centered on the mean line.FIG. 1 Illustration of TerminologyD7127 1323.1.10 surface roughness, nthe combined characteristics of surface profile (height) and peak count (linear density) for asurface.3.1.11 traversing length, nseven sampling lengths comprising the evaluati
22、on length and the pre-travel and post-travelsegments.4. Summary of Test Method4.1 This test method describes the proper use of a portable stylus surface roughness measuring device to evaluate specificsurface parameters and evaluate their suitability for the application of the selected coating to the
23、 surface being prepared by abrasiveblasting, or other mechanical means, prior to application.4.2 The method describes considerations relevant to setup of stylus instruments for acquisition of required surface roughnessparameters.5. Significance and Use5.1 This method may be useful in assuring confor
24、mance of a prepared surface to profile requirements specified by themanufacturer of a protective coating.5.2 This method includes determination of the peak density (number of profile peaks in a specified distance). Some workers inthe field believe that optimizing peak height and peak density can imp
25、rove coating adhesion.5.3 This method allows specifiers to objectively define surface texture after abrasive blast cleaning rather than using subjectiveterms such as “angular pattern” or “dense and uniform pattern.”5.4 Because implicit and explicit definitions of “roughness” may differ substantially
26、, numerical characterizations of profilecannot be compared directly across different methods.6. Apparatus6.1 The apparatus consists of a portable skidded or non-skidded electronic surface roughness measurement instrument (“tester”)capable of measuring Rt,RtRmax in compliance with ISO 4287 and PcRpc
27、in compliance withASME B46.1. The apparatus shouldhave a vertical range of at least 300 m (12 mil) and permit a sampling length of 2.5 mm (0.1 in.) and an evaluation length of 12.5mm (0.5 in.). (Laboratory experience suggests this vertical range is a practical requirement to meet the provisions of 6
28、.2.) In20042009 there are believed to be at least five manufacturersthree manufactures of such devices.56.2 The apparatus should include a stylus with a tip radius of 5 m (0.2 mil), and permit recording of Rt and Rmax in the range10 to 150 mmm (0.4 to 6 mil) and PcRpc up to 180/cm (450/in.).6.3 Surf
29、ace deviations are sensed by the stylus and converted to electrical signals within the device. Internal processing convertsthese signals into standard surface characterization parameters, which are then displayed or printed.7. Preparation of Apparatus7.1 Set the apparatus to display, and, if so equi
30、pped, record the chosen parameters in accordance with the manufacturersinstructions.7.2 The evaluation length should be set to 5 sampling lengths. The sampling length and evaluation length should be set to 2.5mmm (0.1 in.) and 12.5 mmm (0.5 in.), respectively.7.3 The traversing length of the apparat
31、us should be set (or manufacturer preset) to include pre-travel and post-travel segments,usually equal to one sampling length at the beginning and one sampling length at the evaluation length. These portions of a traverseare, however, discarded by the instrument in its calculation of surface paramet
32、ers.7.4 The low frequency (“long wavelength” or “cutoff”) filter should be set to “Gaussian” or “Gaussian 50 %.” In general, thedefault setting will be compliant.7.5 If the apparatus has a high frequency (“short wavelength” or “Ls”) filter should be set to “off.”7.6 The apparatus should be adjusted
33、(if necessary) to a deadband width (C1 = C2) in the range 1.00.5 to 1.252.0 m (40(20to 5080 in.). The choice of deadband for profiles as large as those discussed in this standard will have little effect on themeasurements. In general, the default setting will be compliant.7.7 The accuracy of the app
34、aratus should be calibratedchecked regularly using a standard calibration block available from theequipment manufacturer using their written calibration setup procedure (andFig. 1 ).at their recommended interval.8. Preparation of the Sample8.1 Select a 15 by 15 cm (6 by 6 in.) an area of the surface
35、 to be tested that is visibly free from obvious defects such as scratches,deep marks, or other construction or corrosion defects.5 Research Report to be developed with a listing of manufacturers.D7127 1338.2 Using a stiff nylon bristle brush, remove any dust or abrasive particles from the surface in
36、 the selected sample evaluationarea. If not removed, such dust and micronic metallic particles may cause damage to the stylus and erroneous readings.9. Calibration and Standardization9.1 Precision reproductions of standard surface profiles such as those used by the manufacturer of the equipment, or
37、describedin their operational literature, may be used as calibration standards for the apparatus.10. Procedure10.1 Obtain an initial trace measurement (3(2 parameters), then four more to either side and above and below the first, additionaltrace measurements taken in the compass directions from the
38、original measurement and about 3 cm (1 in.) away (total of 15parameters).for a total of 5 traces, avoiding obvious surface defects.10.2 If the stylus is prevented from making a complete trace due to a physical interference, such as a deep scratch on the surface,move the apparatus to a close adjacent
39、 area away from the obvious defect and repeat the trace.10.3 Record the 1510 parameters resulting from these five traces (3(2 parameters per trace).11. Calculation and Interpretation of Results11.1 Calculate the five measurement average for each of the three parameters.two parameters (Rt and Rpc).12
40、. Report12.1 At a minimum, the report should contain the following items:12.1.1 The sampling length and evaluation length,12.1.2 Jobsite and location at which the measurement was made, and12.1.3 The values of the five trace measurements for each of the three parameters measured (Rt,Rt and Rmax,Rpc a
41、t aminimumPc) and their averages. averages, and12.1.4 Instrument used to obtain the measurements, including model number.12.2 A typical (illustrative) report form is shown in Fig. 2.13. Precision and Bias13.1 The precision of this test method is based on an intralaboratory study conducted in 2011. E
42、leven laboratories participatedin this study, analyzing materials representing five different property types. Each “test result” reported represents an individualdetermination and the participating labs reported three replicate test results for each material type. Practice E691 was followed forthe d
43、esign and analysis of the data; the details are given in ASTM Research Report RR:D01-1169.6 Values in tables appearing inthis section are taken from the foregoing report.13.1.1 The Profile Reproducibility Standard Deviation (Profile SR), documented in Table 1 for each of five levels of profile, iske
44、y to assessing whether a given measurement is statistically different from either an upper or lower profile limit established inadvance by the interested parties.13.1.2 The term “reproducibility standard deviation” is used as specified in Practice E177.13.1.3 Similarly, the Peak Count Standard Devia
45、tion (PC SR), also documented in Table 1, is key to assessing whether a givenmeasurement is statistically different from either an upper or lower peak count limit established in advance by the interested parties.6 Supporting data have been filed at ASTM International Headquarters and may be obtained
46、 by requesting Research Report RR:D01-1169. Contact ASTM CustomerService at serviceastm.org.TABLE 1 Test Method D7127 Profile Measurement StatisticsCoded SurfaceID NumberStylus InstrumentAverage Profile Rt(mils)Stylus InstrumentProfile RtReproducibilityStandard Deviation(mils)SrStylus InstrumentAver
47、age Peak Count(mils)Stylus InstrumentPeak CountReproducibilityStandard Deviation(mils)Sr102 1.18 0.076 174.8 8.4114 2.50 0.210 140.2 7.8124 2.91 0.286 159.3 12.9121 4.06 0.345 92.1 6.7119 4.52 0.356 51.3 3.5D7127 13413.1.4 A measured profile or peak count that is within either limit of a pre-specifi
48、ed range by an amount equal to SR has a 68% probability of satisfying specification. A profile within 1.5 SR of a specified limit has an 86 % probability of satisfyingspecification and a profile within 2.0 SR of a specified limit has a 95 % probability of satisfying the specification. Fig. 2 is a pl
49、ot,using the data in Table 1, of peak count versus measured profile.13.2 PrecisionBiasPortable stylus devices of the kind discussed here are relatively accurate instruments. The primarysource of error arises with the fact that successive measurements of the same surface are not likely to be made at precisely the samelocation.At the time of this study, there was no generally accepted reference method suitable for determining either profile or peakcount bias for this test method, therefore no formal statement on bias is being made.13.2.1 Repe
