1、Designation: F1057 10An American National StandardStandard 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 ofo
2、riginal 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. Scope1.1 This practice covers a procedure for estimating thequality o
3、f extruded poly (vinyl chloride) (PVC) plastic 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 th
4、e user of this standard to establish appro-priate 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
5、.1 Reveal incomplete exsiccation of compound before 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.NOTE 1Residual moisture in the compound v
6、aporizes at extrusiontemperatures and is normally evacuated 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.NOTE 2Minor residual stress in the pipe will not impair fieldperformance an
7、d handleability. High-residual stress has no proven effecton 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
8、 must haveheat generation (power) capacity such that the recoveryachieved 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
9、 the testspecimen.NOTE 3The oven should be vented to the outside of the building.NOTE 4Monitoring 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 specim
10、ens of pipe 150 mm (6 in.) long or longerwith ends cut square so that they stand 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
11、 are 150 mm(6 in.) or longer.4.2 Examine the specimens and note any unusual featuressuch 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
12、 flow freely between the pipes.Place specimens of pipe staves on the floor of the 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). Recover
13、y must occur within 15 min or less.After an additional 30 min of exposure within the 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
14、 pipespecimens lengthwise at approximately 60 circumferentialintervals, resulting in six pipe staves of approximately equalwidths. Cut specimens being tested in the form of staves intothree roughly equal segments. Note the following for thereport:1This practice is under the jurisdiction of ASTM Comm
15、ittee 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 in 1987. Last previous edition approved in 2005 as F105787(2005). DOI:10.1520/F1057-10.1Copyright ASTM International
16、, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.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, and4.4.3 The condition and appearance of the cut edges of thematerial.5.
17、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
18、 was tested;6.1.3 Date of the test;6.1.4 Extent and nature of any distortion at the ends or in thebarrel of the specimen;6.1.5 Condition and appearance of the outer surface;6.1.6 Condition and appearance of the inner surface;6.1.7 Appearance of the cut edges, and6.1.8 Any other changes attributable
19、to the test.7. Precision and Bias7.1 No statement is made about either the precision or biasof Practice F1057 for estimating the quality of PVC pipe, sincethe result merely states whether there is conformance to thecriteria for acceptability suggested by the interpretation.8. Keywords8.1 heat revers
20、ion; PVC pipeAPPENDIX(Nonmandatory Information)X1. SUGGESTED INTERPRETATION OF RESULTSX1.1 The specimens should be deemed to be satisfactory ifnone of the following effects are reported:X1.1.1 Fish-scaling of any severity (see Fig. X1.1) for anillustration of fish-scaling);X1.1.2 Wall separation (se
21、e Fig. X1.2 and Fig. X1.3 forillustrations of wall separation);X1.1.3 Blisters on the outer or inner surface (see Fig. X1.4and Fig. X1.5 for illustrations of blistering);X1.1.4 Contamination made evident by the test (see Fig.X1.4 for an illustration of contamination); andX1.1.5 Wall separation cause
22、d by pockets of granular ma-terial composed of unfused compound or foreign material.(Fig. X1.3 illustrates the general appearance, except that thevoids will be filled with a granular material and may appear atany point in the wall.)F1057 102NOTE 1Severe fish-scaling indicates uneven cooling in the s
23、izing sleeve during extrusion. Resulting wall stresses are released by the heat reversiontest. Note the flared end, another indication of this effect.FIG. X1.1 Severe Fish ScalingF1057 103NOTE 1Severe wall separation reveals the presence of moisture in the extrudate. This usually indicates plugged o
24、r inadequate vacuum control.FIG. X1.2 Severe Wall SeparationF1057 104NOTE 1Less severe wall separation shows the presence of moisture in the extrudate. Poor vacuum control is indicated. Surface blistering may notbe present.FIG. X1.3 Less Severe Wall SeparationF1057 105NOTE 1External blistering is pr
25、onounced in this case and shows the presence of moisture in the extrudate. Less severe blistering requires carefulexamination. Dark axial lines below the number tag are signs of contamination by burnt PVC compound picked up inside the extruder head.FIG. X1.4 External BlisteringF1057 106ASTM Internat
26、ional takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely the
27、ir own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should
28、be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standar
29、ds, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832
30、-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).NOTE 1Internal blistering will usually accompany pronounced external blistering and severe wall separation as an indication of gross vacuum controlproblems.FIG. X1.5 Internal BlisteringF1057 107
