ASTM_G_10_-_10_2015.pdf

Designation:G1010(Reapproved 2015)Standard Test Method forSpecific Bendability of Pipeline Coatings1This standard is issued under the fixed designation G10;the number immediately following the designation indicates the year of originaladoption or,in the case of revision,the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This method covers the specific determination of theeffect of short-radius bends on coatings applied to 33.4-mm(1-in.nominal)diameter pipe.1.2 The values stated in SI units to three significant deci-mals are to be regarded as the standard.The values given inparentheses are for information only.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 the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2G6 Test Method for Abrasion Resistance of Pipeline Coat-ingsG12 Test Method for Nondestructive Measurement of FilmThickness of Pipeline Coatings on Steel(Withdrawn2013)33.Summary of Method3.1 The method consists of bending a 33.4-mm(1-in.nominal)diameter specimen of coated pipe around a mandrelto produce a range of short-radius bends.Coating failure in theform of cracking or loss of adhesion is detected through visualand electrical inspection of the bent specimen.4.Significance and Use4.1 This test will provide information on the ability ofcoatings applied to pipe to resist cracking,disbonding,or othermechanical damage as a result of bending.Because the test isapplied to coated pipe from commercial production,the resultscan be directly used in the selection of similar materials forservice.The test also has application as a quality controlmethod when variations in coating application or materialformulation will affect bending performance.5.Apparatus5.1 The bending apparatus shall be essentially as shown inFigs.1-3 and shall include the following:5.1.1 Variable-Radius Mandrel,constructed from four19-mm(0.75-in.)thick pieces of plywood,bolted together andconforming to the geometric shape shown in Fig.1.Thegeometric construction is accomplished by laying out along theouter edge of the mandrel a series of seven consecutive arcs atdecreasing radii of 610,530,460,380,300,and 230 mm(24,21,18,15,12,and 9 in.).The first five arcs shall be carriedthrough a 45-deg angle to the next point of tangency.A 45-degV-notch shall be cut into the edge of the mandrel for seating thepipe specimen.Holes shall be drilled at appropriate locations inthe mandrel face for positioning the lever arm and fasteningpipe clamps.5.1.2 Lever Arm-Roller AssemblyA 1.83-m(72-in.)leverarm with nylon roller supplies the mechanical advantagenecessary to bend the pipe specimen.The lever arm shallcontain a series of holes which are used to maintain properclearance between the roller and pipe sample during thebending operation.5.2 Thickness GageMeasurements of coating thicknesswill be required for this test.This shall be done in accordancewith Test Method G12.5.3 Holiday DetectorA low-voltage d-c holiday detectorof the wet-sponge type,specified in Test Method G6,shall beused to locate breaks in the coating film.6.Test Specimens6.1 The test specimen should be 2.5 m(100 in.)in length.Itshould be representative of production-coated pipe and be freeof obvious coating flaws or defects.Coating specimens shall beapplied to 33.4-mm(1-in.nominal)diameter pipe.7.Conditioning7.1 The specimen shall be exposed to room temperature fora sufficient time to ensure thermal equilibrium in the pipe and1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.48 on Durability of Pipeline Coating and Linings.Current edition approved Dec.1,2015.Published December 2015.Originallyapproved in 1969.Last previous edition approved in 2010 as G10 10.DOI:10.1520/G0010-10R15.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 coating.A temperature in the range from 20 to 30C(68 to85F)shall be considered room temperature.8.Procedure8.1 Perform the test at a room temperature of 21 to 25C(70to 77F).8.2 Measure the applied coating thickness of each specimenin accordance with Test Method G12.8.3 The time to execute the test at a uniform velocity shouldbe agreed upon by the producer and the user.8.4 Place the conditioned test specimen into the V-notch.