1、Designation: F1025 94 (Reapproved 2011)An American National StandardStandard Guide forSelection and Use of Full-Encirclement-Type Band Clampsfor Reinforcement or Repair of Punctures or Holes inPolyethylene Gas Pressure Pipe1This standard is issued under the fixed designation F1025; the number immedi
2、ately following the designation indicates 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 () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This g
3、uide specifically addresses the design and instal-lation of full-encirclement-type band clamps for repair ofgouges, punctures, or holes, and for reinforcement of polyeth-ylene plastic pipe. Guidelines are provided for selecting andusing clamps in pipe sizes 2 in. nominal (60 mm) and larger.1.1.1 A t
4、est method is also provided for the user to assessthe applicability of the repair clamp. Under appropriate cir-cumstances, this type of clamp offers a convenient, effective,and safe means of restoring the integrity of an in-servicepipeline, without cutting out a section of pipe (see Note 1). Thepipe
5、 to be repaired cannot be backed by a stiffener for internalsupport and cross-sectional dimensional control. Satisfactoryuse of this type of clamp must rely on the crush resistance ofthe pipe itself and a fitting design concept, which retains thecross-sectional pipe configuration while minimizing co
6、mpres-sive forces required to obtain an effective leakage seal.NOTE 1The appropriateness for use of this type of clamp should bedetermined by using the information contained in this guide and fromconsultation with, and recommendations of, both the pipe and clampmanufacturers. The basic premise for u
7、se of this type of clamp is that it isrecommended by the manufacturer for this specific application and thatstep-by-step installation instructions are available for that application. It isimportant in the development of this type of clamp that prototype testingbe conducted to evaluate performance ex
8、pectations because of thephysical limitations encountered when designing it for use with plasticpipe.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not cons
9、idered standard.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
10、.2. Referenced Documents2.1 ASTM Standards:2F1041 Guide for Squeeze-Off of Polyolefin Gas PressurePipe and Tubing3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 creepthe time-dependent part of strain resultingfrom stress, that is, dimensional change caused by the appli-cation
11、of load over and above the elastic deformation and withrespect to time.4. Significance and Use4.1 Full-encirclement-type band clamps are recommendedfor repairs only where the pipe is able to maintain its structuralintegrity. These clamps are not recommended for permanentrepair of pipe where the dama
12、ge could propagate outside theclamp under anticipated field conditions (see 5.1.1 for repairlimitations). In such situations, cut out and replace the dam-aged pipe with a new piece.4.2 These clamps may be used to cover holes left in the pipefrom abandoned service line connections, purge points, anda
13、ccidental punctures.4.3 These clamps may be used to reinforce the pipe wherethe wall thickness has been reduced because of gouges or otherirregularities.4.4 Some users reinforce polyethylene pipe after it has beensqueezed-off as a precaution against pipe damage that mayhave occurred during the squee
14、ze-off process and as a means of1This guide is under the jurisdiction of ASTM Committee F17 on Plastic PipingSystems and is the direct responsibility of Subcommittee F17.60 on Gas.Current edition approved Aug. 1, 2011. Published August 2011. Originallyapproved in 1986. Last previous edition approved
15、 in 2006 as F1025 94 (2006).DOI: 10.1520/F1025-94R11.2For 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.1Copyrig
16、ht ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.ensuring that the pipe will not be squeezed-off again at thesame location. Consult with the polyethylene pipe manufac-turer as to the appropriateness of squeeze-off for their product,and for ci
17、rcumstances when reinforcement is recommended.See Guide F1041.5. General Considerations5.1 The following general considerations apply to determinethe appropriateness of using full-encirclement-type bandclamps:5.1.1 Type or Extent of FailureConsider repairs only to aclean-cut round hole or deep scrat
18、ches or gouges of maximumdimension, less than the nominal diameter of the pipe dividedby three. Do not repair pipe with cracks, jagged punctures, longtears, or deep scratches or gouges which could propagateoutside the clamp under anticipated field loads. Cut out andreplace the damaged pipe with a ne
19、w piece.5.1.2 Pipe/Clamp ProfileThis type of clamp is usuallymade from flexible materials which have minimal ring stiff-ness. The clamp, by design, must rely on the pipe itself for anassembled profile and resistance to deformation from second-ary loading.5.1.3 Creep Properties of Pipe Material Creep
20、 propertiesaffect both the pipe strength and its dimensional change. Asresistance to creep increases, stiffness increases and dimen-sional change decreases.5.1.4 Minimum Pipe SizeNormally full-encirclement-typeband clamps have a minimum pipe size limitation due to thebasic design characteristics and
21、 the need to develop minimumsealing pressures against the pipe. The pipe must also be strongenough to resist anticipated secondary loading.5.1.5 Pipe Dimension Ratio (DR)The DR is determinedby dividing the specified average outside diameter of the pipeby the minimum specified wall thickness.Alower D
22、R providesgreater resistance to pipe deformation and creep.5.1.6 In-service Internal PressureHigher pressures tendto internally support the existing pipe dimensions and roundprofile.5.1.7 In-service Operating Temperature Increased tem-peratures lower pipe stiffness and creep resistance.6. Design Rec
23、ommendations6.1 Properly designed full-encirclement-type band clampsshould meet the following recommendations:6.1.1 Maximum allowable operating pressure (MAOP) of100 psig (689 kPa).6.1.2 Maximum and minimum allowable operating tem-perature limits are provided by the manufacturer.6.1.3 All components
24、 of the clamp are made fromcorrosion-resistant material, such as stainless steel, fiber-reinforced composite, or other plastic approved for use onburied polyethylene gas piping.6.1.4 The clamp is designed and made of material whichdoes not cause the pipe profile (ring) to assume a differentshape aft
25、er being installed.6.1.5 The clamp materials have sufficient long-term strengthto last as long as the expected life of the pipe being clamped.6.1.6 The clamp, including the gasket, encircles the pipeand provides 360 reinforcement of the pipe.6.1.7 The gasket material is suitable for the intended ser
26、viceand of such hardness that significant compression of the pipe isnot required to maintain a seal.6.1.8 The interface between the clamp and gasket materialmaintains the position of the gasket within the band configu-ration.6.1.9 The dimensions of the clamp compensate for expectedcircumferential co
27、mpression of the pipe, thereby ensuring apressure seal when the pipe is in the contracted position.7. Installation Recommendations7.1 Refer to the general considerations stated in Section 5 ofthis guide to determine the appropriateness of using full-encirclement-type band clamps to repair plastic pi
28、pe.7.2 Select a clamp with a length at least 112 times thenominal diameter of the pipe, but not less than 9 in. (229 mm)long.7.3 Use on pipe which is clean and free of any irregularitiesthat affect its profile.7.4 Center the clamp over the area to be repaired.7.5 Install the clamp in accordance with
29、 the clamp manu-facturers recommended procedures.7.6 Leak test the repaired area using an appropriate leakdetector to validate the repair.8. Test Method8.1 This test is recommended as a means for the user toassess the applicability of a candidate repair clamp for use withpolyethylene gas pipe. The u
30、ser may also wish to performadditional tests (that is, pipe deflection), relevant to the specificintended use.NOTE 2The manufacturer is responsible for selecting a test appropri-ate to the intended applications for its product. Repair limitations,installation requirements, and performance expectatio
31、ns should be madeavailable to users by the manufacturer.NOTE 3It is not intended that this or any other user test be the onlytest method used for product qualification.8.2 Select a pipe specimen with a hole size slightly less thanthe nominal diameter of the pipe divided by 3 (that is, 3 in.nominal (
32、89 mm) SDR 11.0 pipe with 1.125-in. (26.6-mm)hole); and of sufficient length to extend at least 12 in. (305 mm)beyond both ends of the clamp being tested.8.3 Select a clamp as specified in 7.2, and center it over thearea to be tested.8.4 Install the clamp following the pipe and clamp manu-facturers
33、recommended installation procedures.8.5 Provide suitable end closures for pressure testing.8.6 Once installed, do not adjust the clamp or retorque bolts.8.7 At 73F (23C), pressurize the specimen to 100 psig(689 kPa) with suitable test fluid and check for leakage.Reduce the pressure to 5 psig (34 kPa
34、).8.7.1 Condition the specimen for 24 h at the lowest operat-ing temperature anticipated by the user. Check again forleakage. Allow the specimen to stabilize at room temperaturefor another 24 h and recheck for leakage.8.7.2 Condition the specimen for 24 h at the highestoperating temperature anticipa
35、ted by the user. Check again forleakage. Allow the specimen to stabilize at room temperaturefor another 24 h and recheck for leakage.F1025 94 (2011)2NOTE 4Most of the significant creep occurs within the first 1000 h.Since the application of a mechanical clamp on polyethylene pipe resultsin a rapidly
36、 decreasing load because of the initial gasket and pipedeformation, laboratory installations, corroborated by field experience,indicate that visible deformation occurs within 24 to 48 h after the clampis installed. Further deformation with time is not of the magnitudenecessary to affect the original
37、 pressure seal provided by a suitable clamp.8.8 Remove the clamp and end closures of the specimen andvisually inspect the inside and outside of the pipe that wasbeneath the clamp for cracks or other damage caused by theclamp.9. Rejection9.1 Any leakage detected during the test constitutes failureof
38、the specimen.9.2 Any signs of splitting or cracking in the pipe constitutesrejection of the specific pipe and clamp assembly being tested.10. Keywords10.1 damage; full-encirclement-type band clamp; hole; leakrepair; pipe reinforcement; plastic pipe; punctureASTM International takes no position respe
39、cting 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 st
40、andard 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 Internat
41、ional 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 belo
42、w.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/).F1025 94 (2011)3
