1、Designation: F 1057 87 (Reapproved 2005)An 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 F 1057; the number immediately following the designation in
2、dicates 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers a procedure for es
3、timating thequality of extruded poly (vinyl chloride) (PVC) plastic pipes byobserving the reaction of pipe specimens after exposure toheat.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
4、 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:2.1.1 Reveal incomplete exsic
5、cation 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 vaporizes at extrusiontempe
6、ratures 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 and handleability. High-resi
7、dual 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) such that after insertion of thespecimen to be tested the test temperature is regained within 15min or
8、less.NOTE 3The oven should be vented to the outside of the building.4. Procedure4.1 Prepare specimens 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 specim
9、ens 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 featuressuch as discoloration, inclusions, or pinholes in the cut edge.4.3 Place the specimens of whole pipe in the preheated
10、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 preheatedoven so that they rest on their longitudinal edges and so that hotair can flow freely around them. Record the t
11、ime when the airin the oven recovers to 180C (356F). After an additional 30min at this temperature, remove the specimens, taking care notto 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 lengthwis
12、e 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:4.4.1 The shape of the pipe ends and the pipe barrel,4.4.2 The condition and
13、appearance of both the inner andouter surfaces of the material, and4.4.3 The condition and appearance of the cut edges of thematerial.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 I
14、nformation 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 tested;1This practice is under the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F 17.40 on Tes
15、tMethods.Current edition approved August 1, 2005. Published August 2005. Originallyapproved in 1987. Last previous edition approved in 2000 as F105787(2000).1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.1.3 Date of the test;6.1.4
16、 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 to the test.7. Precision and Bias7.1 No
17、statement is made about either the precision or biasof Practice F 1057 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 reversion; PVC pipeAPPENDIX(Nonmandatory Info
18、rmation)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 (see Fig. X1.2 and Fig. X1.3 forillustrati
19、ons 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 caused by pockets of granular ma-terial comp
20、osed 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.)F 1057 87 (2005)2NOTE 1Severe fish-scaling indicates uneven cooling in the sizing sleeve during extrusion.
21、Resulting wall stresses are released by the heat reversiontest. Note the flared end, another indication of this effect.FIG. X1.1 Severe Fish ScalingF 1057 87 (2005)3NOTE 1Severe wall separation reveals the presence of moisture in the extrudate. This usually indicates plugged or inadequate vacuum con
22、trol.FIG. X1.2 Severe Wall SeparationF 1057 87 (2005)4NOTE 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 SeparationF 1057 87 (2005)5NOTE 1External blistering is pronounce
23、d 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 BlisteringF 1057 87 (2005)6ASTM Interna
24、tional 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 th
25、eir 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
26、 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 Standa
27、rds, 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 610-83
28、2-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).NOTE 1Internal blistering will usually accompany pronounced external blistering and severe wall separation as an indication of gross vacuum controlproblems.FIG. X1.5 Internal BlisteringF 1057 87 (2005)7
