1、Designation: C1147 01 (Reapproved 2012)Standard Practice forDetermining the Short Term Tensile Weld Strength ofChemical-Resistant Thermoplastics1This standard is issued under the fixed designation C1147; the number immediately following the designation indicates the year oforiginal adoption or, in t
2、he 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 the preparation and evaluation ofjoints between two pieces of we
3、ldable grades of thermoplasticmaterials, backed and unbacked, (such as those shown in Table1) up to 2 in. (50 mm) in thickness.1.2 Since there are numerous new technologies and tech-niques constantly being developed for plastic welding, thereare no profiles and procedures that can be considered asst
4、andard for all plastics at various thicknesses. This practice isnot intended to define profiles and procedures; however, it isintended to establish methods to evaluate minimum short termweld factors to be achieved by the welder for the respectiveplastics.1.3 Weld procedures used for test pieces shou
5、ld reflectprocedures to be used in actual fabrication.1.4 Welding methods to be used could include machinewelding, extrusion welding, and hot gas welding.1.5 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units t
6、hat are provided for information onlyand are not considered standard.2. Referenced Documents2.1 ASTM Standards:2C904 Terminology Relating to Chemical-Resistant Nonme-tallic MaterialsD4285 Test Method for Indicating Oil or Water in Com-pressed AirE4 Practices for Force Verification of Testing Machine
7、s3. Terminology3.1 Definitions For definitions of terms used in thispractice, see Terminology C904.4. Summary of Practice4.1 The sheets are prepared and welded. Tensile test speci-mens containing a section of the weld are prepared and tested.Specimens of unwelded sheet are tested and compared to the
8、welded specimens. The short term weld factor determined iscompared to the standard (see Table 2), or to the factor agreedupon between the supplier and the user.5. Significance and Use5.1 The mechanical performance of welded thermoplasticstructures is largely dependent on the quality of the weldingop
9、eration. Fabricators should determine that the proper weld-ing procedures are being followed and that welders maintaintheir proficiency. Results from this practice are indicative ofskill in proper welding procedures for different thermoplasticmaterials and the use of appropriate welding equipment. I
10、f thewelded test specimens have short term weld factors that meetor exceed the minimums as set forth in this practice, or asagreed to by supplier and user, it may be concluded that, withthe same degree of skill and diligence by the welder, acceptablewelds should be obtained in fabricated structures.
11、6. Apparatus6.1 The apparatus for welding shall consist of the following:6.1.1 Welding Device, suitable for joining thermoplastics.6.1.2 Air Supply, when needed, conforming to Test MethodD4285.6.1.3 Temperature Measuring Device , capable of measur-ing the welding temperature to within 61 % for the s
12、pecificplastic as set forth in Table 1.6.1.4 Clamps, suitable for holding the specimen whilewelding.6.1.5 Saw, suitable for cutting thermoplastic sheet.6.1.6 Sander, Router, Joiner, or Saw, suitable for bevelingedges of sheet.6.2 The apparatus for testing tension specimens shall consistof the follow
13、ing:6.2.1 Tensile Machine A testing machine capable of pull-ing the specimens at a rate of 2 6 0.1 in./min (50 6 2.5mm/min) of crosshead movement (speed of movement whenthe machine is running without a load).1This practice is under the jurisdiction of ASTM Committee C03 on Chemical-Resistant Nonmeta
14、llic Materials and is the direct responsibility of SubcommitteeC03.03 on Thermoplastics, Thermosets and Elastomers.Current edition approved Aug. 1, 2012. Published September 2012. Originallyapproved in 1990. Last previous edition approved in 2006 as C1147 01 (2006).DOI: 10.1520/C1147-01R12.2For refe
15、renced 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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West
16、 Conshohocken, PA 19428-2959. United States16.2.1.1 The rate of movement between heads of the testingmachine shall remain essentially constant under changing loads(see Note 1).NOTE 1It is difficult to meet this requirement when loads aremeasured with a spring type or pendulum type weighing device.6.
17、2.1.2 The testing machine shall measure the load to within1 %. The testing range shall be so selected that the maximumload on the specimen falls between 15 and 85 % of the fullscale capacity.6.2.1.3 The use of autographic equipment to record the loadversus head movement is recommended.6.2.1.4 Verifi
18、cation of the testing machine shall be made inaccordance with the recommendations of Practices E4.6.2.2 Micrometer or Vernier Caliper , suitable for measur-ing width and thickness of the test specimen to the nearest0.001 in. (0.025 mm).7. Test Specimens7.1 Test Pieces For Hot Gas and Extrusion Weldi
19、ngStartwith a 10 by 42 in. (250 by 1050 mm) piece of plastic sheet ofthe type and thickness to be tested. Cut the sheet as shown inFig. 1 to yield five pieces, four measuring 5 by 18 in. (125 by450 mm) and one measuring 6 by 10 in. (150 by 250 mm). Two5 by 18 in. pieces will be used for horizontal w
20、elding and two5 by 18 in. pieces for vertical welding.7.1.1 The 6 by 10 in. sample will be cut into controlspecimens as described in Section 7.2.2. Label each piece as totype of plastic, method of welding, orientation of welding andwelder identification.7.1.2 Edge Preparation Bevel one 18 in. (450 m
21、m) edgeof each 5 by 18 in. piece in preparation for welding. Bevelingshall be done using suitable apparatus such as routers, sanders,joiners, or saws, that accurately reflect methods utilized in thefield. Typical bevel profiles for the various sheet thicknessesare illustrated in Fig. 2 and Fig. 3. T
22、hese profiles are optionaland do not have to be used by the fabricator to meet the weldtest standard, however, experience has shown that the use ofbeveled edges is advantageous to weld quality in sheet greaterthan 60 mils (1.5 mm) in thickness in hot gas and extrusionwelding processes. Do not use so
23、lvents or other chemicals forcleaning the beveled surfaces that in any way will adverselyaffect the properties of the plastic. The cleaning operationshould not in any way alter the profile or bevel of the edge.Details of bevels and test procedures used should accompanytest specimens and the report o
24、f test results.7.1.3 Welding ProcedureSecurely clamp the test sheets tobe welded to a suitable fixture and adjust welding devicetemperature as specified in Table 1. Weld two specimens, onevertically to simulate tank walls, and one horizontally tosimulate tank floors. If a machine such as a hot plate
25、 welder orother equipment that is in a fixed position is being used, thetwo test specimens, cut and configured as in 7.1, are welded inTABLE 1 Typical Guide for Hot Gas Welding TemperaturesNOTE 1For other welding techniques, consult material and equipmentsupplier for recommendations.FARecommended Ga
26、s TypeBHDPE 500600 Nitrogen or AirPP 550600 Nitrogen or AirPVC 500550 AirCPVC 550660 AirPVDF 650680 Nitrogen or AirECTFE 665695 NitrogenETFE 675710 AirFEP 650725 AirPFA 675750 AirMFA 536554 AirAMeasured14 in. inside weld tip, directly in gas stream.BInert gas may be used in place of air.TABLE 2 Mini
27、mum Short Term Weld FactorsThermoplastic Hot Gas Extrusion Hot PlateHDPE 0.8 0.8 0.9PP 0.8 0.8 0.9PVC 0.8A0.9CPVC 0.6A0.8PVDF 0.8 0.8 0.9ECTFE 0.9 0.9 0.9ETFE 0.9 0.9 0.9FEP 0.9 0.9 0.9TFE (PFA Filler) 0.9 0.9APFA 0.9 0.9 0.9ANot applicable.FIG. 1 Test PiecesFIG. 2 Typical Bevel Profile (Sheet 0.090
28、 to 0.5 in. (2.3 mm to 13mm) in Thickness)C1147 01 (2012)2the machines normal welding plane. The two samples shallnot be welded in the same cycle of the machine. Weldingprocedures must be identified and adequately described as partof the report. The completed weld may be projecting above orbe flush
29、with adjacent surfaces.7.2 Preparation of Test Specimens :7.2.1 Weld Test SpecimensCut and discard a 1 in. strip offeach end of an 18 by 10 in. welded specimen resulting in apiece 16 by 10 in. (400 by 250 mm). Cut remaining pieceacross the weld into 1 6 0.01 in. (25 6 0.25 mm wide) by 10in. (250 mm)
30、 long strips. The width of the test specimens canbe varied depending on the capacity of the tensile machine andthe type and thickness of plastic being tested. Set aside at least10 of these specimens from the vertically welded sample andthe same number from the horizontal for weld test evaluationand
31、condition a minimum of 16 h at 73 6 4F (23 6 2C).7.2.2 Control SpecimensCut 5 pieces off the 6 by 10 in.control specimen to the same dimensions as welded testspecimens. Condition at least 5 specimens for evaluation for 16hat736 4F (23 6 2C).8. Test Procedure8.1 Tensile Strengths:8.1.1 Control Specim
32、ensMeasure width and thickness ofthe test pieces to the nearest 0.001 in. (0.025 mm) at theone-third intervals of that length not held by the grips. Recordthe respective measurements, calculate the respective cross-sectional areas, and calculate the average cross-sectional areaof test pieces.8.1.1.1
33、 Conduct the tensile test using a suitable test machinepulling at a cross-head speed of 2 6 0.1 in. (50 6 2.54mm)/min.8.1.2 Welded Specimens Measure width and thickness ofthe test pieces to the nearest 0.001 in. (0.025 mm) at theone-third intervals of that length not held by the grips. Do notmeasure
34、 thickness within14 in. (6 mm) of the weld bead area.Record the respective measurements, calculate the respectivecross-sectional areas and calculate the average cross-sectionalarea of test pieces.8.1.2.1 Conduct the tensile test using a suitable test machinepulling at a cross-head speed of 2 6 0.1 i
35、n. (50 6 25.4mm)/min.9. Calculation9.1 Calculate the tensile strengths of each specimen asfollows:S 5 P/A (1)where:S = tensile strength, psi (MPa),P = peak load lbf (or N), andA = average cross-sectional area, in.2(or mm2).9.1.1 Average cross-sectional area is the product of theaverage width and ave
36、rage thickness for each individualspecimen as measured in 8.1.1 and 8.1.2.9.1.2 When fabric backed sheet is tested, the overallthickness, including the fabric, shall be used in determining thethickness measurements in 8.1.1 and 8.1.2.9.2 Control Strength Calculate the average sheet strengthof the 5
37、control specimens.9.3 Short Term Weld FactorCalculate the short term weldfactors for each vertically and horizontally welded specimen asfollows:Short Term Weld Factor 5Weld Strength, psi MPa!Average Control Strength, psi MPa!(2)9.4 All weld factors of the test specimens shall meet orexceed the value
38、s for the type of thermoplastic material listedin Table 2 or as agreed to between the supplier and user. If anyspecimens fail to meet or exceed the specified values, thewelder is not considered certified and shall resubmit newlyprepared specimens for retesting. Subsequent failures shouldcall for inv
39、estigation of the technique and equipment.10. Report10.1 Report the following information:10.1.1 At the time the test specimens are provided fortesting, welder shall provide details of weld joint techniques asrequired in Section 7, which should include profile, type ofweld equipment, type of gas and
40、 flow rate, temperatures used,type and nominal thickness of plastic sheet and rod, andmethod of bevel preparation, if any.10.1.2 Identification of the welder and the date of testspecimen fabrication shall be recorded.10.1.3 Weld strengths of all of the welded specimens, thefive control specimens, an
41、d the calculated short term weldfactors shall be reported.11. Welder Proficiency11.1 All welders engaged in the fabrication of structuresintended to hold, contain, or convey corrosive chemicals shallbe evaluated in accordance with the mandates of this practice.11.2 To maintain qualification, welders
42、 shall, at least once ayear, prepare and have tested, according to this practice, testspecimens of each combination of plastics and welding equip-ment for which they wish qualification. Results achieved shallFIG. 3 Typical Bevel Profile (Sheet 0.5 in. (13 mm) Thick)C1147 01 (2012)3be in accordance w
43、ith the requirements given in 9.4. Testresults shall be maintained in the personnel file of the welderand should be made available to customers upon request.12. Keywords12.1 chemical resistant; plastics welding; short term weldfactor; thermoplastic; weldingASTM International takes no position respec
44、ting 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 their own responsibility.This sta
45、ndard 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 be addressed to ASTM Internati
46、onal 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 Standards, at the address shown below
47、.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 610-832-9585 (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/).C1147 01 (2012)4
