1、Designation:F105710Standard Practice forEstimating the Quality of Extruded Poly(Vinyl Chloride)(PVC)Pipe by the Heat Reversion Technique1This standard is issued under the fixed designation F1057;the number immediately following the designation indicates the year oforiginal adoption or,in the case of
2、 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 practice covers a procedure for estimating thequality of extruded poly(vinyl chloride)(PVC)plast
3、ic pipes byobserving the reaction of pipe specimens after exposure to hotair in the oven at 180 6 5C for 30 min duration.1.2 This standard does not purport to address all of thesafety problems,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-pria
4、te safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Significance and Use2.1 This practice is applicable to distinguish between prop-erly and improperly extruded PVC plastic pipe.It can be usedto:2.1.1 Reveal incomplete exsiccation of compound befo
5、re orduring extrusion(Note 1),2.1.2 Determine the presence of stress in the pipe wallproduced by the extrusion process(Note 2),2.1.3 Determine whether infused areas are present,and2.1.4 Reveal contamination.NOTE1Residual moisture in the compound vaporizes at extrusiontemperatures and is normally eva
6、cuated as it forms vapor.Pockets ofmoisture trapped in the pipe wall result from incomplete exsiccation of thecompound,and may reduce the physical properties of the pipe.NOTE2Minor residual stress in the pipe will not impair fieldperformance and handleability.High-residual stress has no proven effec
7、ton performance,but may impair handleability during installation.3.Apparatus3.1 Air Oven,thermostatically controlled,capable of oper-ating at 180 6 5C(356 6 9F)and capable of meeting therecovery requirement of 4.3.Additionally,the oven must haveheat generation(power)capacity such that the recoveryac
8、hieved while at a constant oven set point.The air temperaturewith the oven(that is,the test temperature)is to be monitoredwithin 3 in.from the outer edge of the test specimen;makeassurances that the temperature does not contact the testspecimen.NOTE3The oven should be vented to the outside of the bu
9、ilding.NOTE4Monitoring of the test temperature within the oven mayrequire a secondary temperature monitoring device in addition to thetemperature monitoring device within the oven control system.4.Procedure4.1 Prepare specimens of pipe 150 mm(6 in.)long or longerwith ends cut square so that they sta
10、nd perpendicular on endwhen placed in the oven.4.1.1 Cut staves from pipes whose size prevents insertion offull round specimens in the oven.Prepare large-diameter pipestaves so that their lengths parallel to the pipe axis are 150 mm(6 in.)or longer.4.2 Examine the specimens and note any unusual feat
11、uressuch as discoloration,inclusions,or pinholes in the cut edge.4.3 Place the specimens of whole pipe in the preheated ovenso that each specimen stands on end with sufficient separationbetween them so that hot air can flow freely between the pipes.Place specimens of pipe staves on the floor of the
12、preheatedoven so that they rest on their longitudinal edges and so that hotair can flow freely around them.Record the time when the airin the oven directly adjacent to the test specimen recovers to180C(356F).Recovery must occur within 15 min or less.After an additional 30 min of exposure within the
13、testtemperature tolerance of 180 6 5C,remove the specimens,taking care not to alter any heat effects.4.4 Examine the specimens within 3 min after removal fromthe oven,while still hot.With a sharp knife,cut whole pipespecimens lengthwise at approximately 60 circumferentialintervals,resulting in six p
14、ipe staves of approximately equalwidths.Cut specimens being tested in the form of staves intothree roughly equal segments.Note the following for thereport:4.4.1 The shape of the pipe ends and the pipe barrel,4.4.2 The condition and appearance of both the inner andouter surfaces of the material,and4.
15、4.3 The condition and appearance of the cut edges of thematerial.1This practice is under the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.40 on TestMethods.Current edition approved May 1,2010.Published June 2010.Originallyapproved i
16、n 1987.Last previous edition approved in 2005 as F105787(2005).DOI:10.1520/F1057-10.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Interpretation5.1 A suggested interpretation of the results observed isgiven in Appendix X1.6.Report6.1 Report the following information,where applicable:6.1.1 Information given by the pipe marking,including thenominal size of pipe,the type of pipe,and the date code;6.1.2 Form in which the pipe was test
