1、Designation: D2855 96 (Reapproved 2010)An American National StandardStandard Practice forMaking Solvent-Cemented Joints with Poly(Vinyl Chloride)(PVC) Pipe and Fittings1This standard is issued under the fixed designation D2855; the number immediately following the designation indicates the year ofor
2、iginal 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.This standard has been approved for use by agencies of the Department of
3、Defense.1. Scope1.1 This practice describes a procedure for making jointswith poly(vinyl chloride) plastic (PVC) pipes, both plain endsand fittings, and bell ends, by means of solvent cements. Theseprocedures are general ones for PVC piping. In non-pressureapplications, simplified procedures may be
4、used. Manufactur-ers should supply specific instructions for their particularproducts, if and when it seems necessary.1.2 The techniques covered are applicable only to PVCpipe, both plain and bell-end, and fittings of the same classes asdescribed in Specification D1784.1.3 Pipe and fittings are manu
5、factured within certain toler-ances to provide for the small variations in the extrusion,belling, and molding processes and are not to exact size. Apartial list of standards for PVC pipe, fittings, and cementssuitable for use in making solvent-cemented joints is given inAppendix X1.1.4 The values st
6、ated 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 considered standard.1.5 The text of this practice references notes and footnotesthat provide explanatory material. These n
7、otes and footnotes(excluding those in tables and figures) shall not be consideredas requirements of the practice.1.6 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 sa
8、fety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D740 Specification for Methyl Ethyl KetoneD1600 Terminology for Abbreviated Terms Relating toPlasticsD1784 Specification for Rigid Poly(Vinyl Chloride) (PVC)Co
9、mpounds and Chlorinated Poly(Vinyl Chloride)(CPVC) CompoundsD2564 Specification for Solvent Cements for Poly(VinylChloride) (PVC) Plastic Piping SystemsF402 Practice for Safe Handling of Solvent Cements, Prim-ers, and Cleaners Used for Joining Thermoplastic Pipe andFittingsF412 Terminology Relating
10、to Plastic Piping SystemsF656 Specification for Primers for Use in Solvent CementJoints of Poly(Vinyl Chloride) (PVC) Plastic Pipe andFittings3. Terminology3.1 DefinitionsDefinitions are in accordance with Termi-nology F412, and abbreviations are in accordance with Termi-nology D1600, unless otherwi
11、se specified.4. Summary of Practice4.1 To consistently make good joints, the following shouldbe clearly understood and adhered to:4.1.1 The joining surfaces must be softened (dissolved) andmade semi-fluid.4.1.2 Sufficient cement must be applied to fill the gapbetween pipe and fitting.4.1.3 Assembly
12、of pipe and fittings must be made while thesurfaces are still wet and fluid.1This practice is under the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.20 on Joining.Current edition approved Feb. 1, 2010. Published March 2010. Original
13、lyapproved in 1970. Last previous edition approved in 2002 as D2855 96(2002).DOI: 10.1520/D2855-96R10.2For 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
14、Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.1.4 Joint strength develops as the cement dries. In the tightpart of the joint the surfaces will tend to fuse together; in theloose part the c
15、ement will bond to both surfaces.4.2 Penetration and dissolving can be achieved by thecement itself, by a suitable primer, or by the use of both primerand cement. A suitable primer will penetrate and dissolve theplastic more quickly than cement alone. In cold weather, moretime and additional applica
16、tions are required (see Fig. 1).4.3 More than sufficient cement to fill the loose part of thejoint must be applied (see Fig. 2). Besides filling the gap,adequate cement layers will penetrate the surfaces and alsoremain wet until the joint is assembled.4.4 If the cement coatings on the pipe and fitti
17、ngs are wetand fluid when assembly takes place, they will tend to flowtogether and become one cement layer. Also, if the cement iswet the surfaces beneath them will still be soft, and thesedissolved surfaces in the tight part of the joint will tend to fusetogether (see Fig. 3).4.5 As the solvent dis
18、sipates, the cement layer and thedissolved surfaces will harden with a corresponding increase injoint strength. A good joint will take the required workingpressure long before the joint is fully dry and final strength isobtained. In the tight (fused) part of the joint, strength willdevelop more quic
19、kly than in the looser (bonded) part of thejoint. Completed joints should not be disturbed until they havecured sufficiently to withstand handling. Joint strength devel-ops as the cement dries. Information about the development ofbond strength of solvent cemented joints is available (see Fig.4).5. S
20、ignificance and Use5.1 The techniques described herein can be used to producestrong pressure-tight joints between PVC pipe and fittings,either in shop operations or in the field. However, skill andknowledge on the part of the operator are required to obtain agood quality joint.This skill and knowled
21、ge can be obtained bymaking joints under the guidance of skilled operators andtesting them until good quality joints are obtained.6. Materials6.1 Pipe and FittingsThe pipe and fittings should meetthe requirements of current applicable PVC piping standards.Alist of these standards is given in Appendi
22、x X1.6.2 Solvent Cement:6.2.1 SpecificationThe solvent cement should meet all therequirements of Specification D2564.6.2.2 SelectionPVC solvent cements are available in avariety of viscosities and wet film thicknesses to cover therange of pipe sizes from18 to 12 in. and for interference-fitjoints as
23、 well as noninterference joints, as found in someSchedule 80 pipe and fittings. One of the general principles ofsolvent cementing that should be strictly adhered to is: suffi-cient cement must be applied to fill the gap between pipe andfitting.6.2.2.1 The ability of a solvent cement to fill a gap in
24、 a pipejoint can be determined by considering its viscosity andwet-film thickness (see Note X3.1). A guide to the properselection of a solvent cement for the various pipe sizes is givenin Table X3.1 and Table X3.2, where PVC solvent cements areclassified (for purposes of identification) as regular-b
25、odied,medium-bodied, and heavy-bodied cement based on minimumviscosity and minimum wet-film thickness.6.2.3 StoragePVC solvent cements should be stored in acool place except when actually in use at the job site. Thesecements have a limited shelf life when not stored in hermeti-cally sealed container
26、s. Screw top containers are not consid-ered to be hermetically sealed. Consult the cement manufac-turer for specific storage recommendations on storageconditions and shelf life. The cement is unsuitable for use onFIG. 1 Areas of Pipe and Fittings to Be Softened (Dissolved) andPenetratedFIG. 2 Cement
27、 Coatings of Sufficient ThicknessFIG. 3 Assembly of Surfaces While They Are Wet and SoftFIG. 4 Bonded and Fused Surfaces of Joined PipeD2855 96 (2010)2the job if it exhibits an appreciable change from the originalviscosity, or if a sign of gelation is apparent. Restoration of theoriginal viscosity o
28、r removal of gelation by adding solvents orthinners is not recommended.6.3 CleanersCleaners are of two types, chemical andmechanical (abrasives). Cleaners are used to remove surfaceimpurities (oil, dirt, etc.) and surface gloss.6.3.1 Chemical CleanersThe chemical cleaners are asfollows:6.3.1.1 Clean
29、er recommended by the pipe, fittings, or ce-ment manufacturer, and6.3.1.2 Methyl ethyl ketone (MEK) in accordance withSpecification D740.6.3.2 Mechanical CleanersThe mechanical cleaners areas follows:6.3.2.1 Fine abrasive paper or cloth (180 grit or finer), and6.3.2.2 Clean, oil-free steel wool.6.4
30、PrimersPrimers are used to clean, soften, and dissolvethe joining surfaces in order to better prepare them for solventcementing. Primers must be capable of dissolving 10 weight %of PVC resin as required in Specification F656. Primers mayalso be used as cleaners; refer to specific recommendations oft
31、he manufacturer.NOTE 1In the event of conflicting instructions from the pipe, fittings,or cement manufacturer, use a primer as well as solvent cement in thejoining procedure.6.4.1 Primer SpecificationThe primer shall meet the re-quirements of Specification F656.7. Procedure7.1 Cutting the PipeCut pi
32、pe square with the axis, usinga fine-tooth hand saw and a miter box, or a fine-tooth powersaw with a suitable guide (see Fig. 5). Wood-working bladesmay be used. A rotary cutter may be used if the cutting bladesare specifically designed for cutting plastic pipe in such a wayas not to raise a burr or
33、 ridge (flare) at the cut end of the pipe.If other tools are not available, a standard rotary metal pipecutter may be used, provided great care is taken to remove allthe ridge raised at the pipe end by the wedging action of thecutting wheels. Failure to remove the ridge will result in thecement in t
34、he fitting socket being scraped from the socketsurface, producing a dry joint with a high probability of jointfailure. Remove all burrs with a knife, file, or abrasive paper.7.2 Joint PreparationChamfer or deburr pipe, or both,approximately as illustrated in Fig. 6. Failing to chamfer theedge of the
35、 pipe may remove the cement and softened materialfrom the fitting socket, and result in a leaking joint.7.3 Test Dry Fit of the Joint (see Fig. 7)The solventcement joint is designed so that there will generally beinterference of pipe wall with the fitting socket before the pipeis fully inserted. Ins
36、ert the pipe into the fitting and check thatthe interference occurs about13 to23 of the socket depth.Sometimes, when the pipe and fittings are at their toleranceextremes or when Schedule 80 pipe is used, it may be possibleto fully insert the dry pipe into the fitting socket until itbottoms. If this
37、occurs, the fit between the pipe and fittingshould be snug. If the fit is loose or wobbly, other fittings orpipe should be selected which give a proper fit.7.4 CleaningSurfaces to be joined must be cleaned and befree of dirt, moisture, oil, and other foreign material (see Fig.8). If this cannot be a
38、ccomplished by wiping with a clean drycloth, a chemical or mechanical cleaner must be used. If achemical cleaner is used, apply with an applicator. Skin contactwith chemical cleaners should be avoided.7.5 Application Procedure:7.5.1 Handling CementKeep the cement can closed andin a shady place when
39、not actually in use. Discard the cementwhen an appreciable change in viscosity takes place, or at thefirst sign of gelation. The cement should not be thinned. Keepthe brush immersed in cement between applications.NOTE 2A gel condition is indicated when the cement does not flowfreely from the brush o
40、r when the cement appears lumpy and stringy.7.5.2 Applicator SizeApply the cement with a naturalbristle, nylon brush or suitable applicator, using a12-in.(12-mm) brush or dauber for nominal pipe size12-in. and less,a 1-in. (25-mm) brush or dauber for pipe up through 2-in.nominal pipe size, and a bru
41、sh width at least12 of nominal pipesize for sizes above 2 in., except that for pipe sizes 6 in. andlarger a 212-in. (60-mm) brush is adequate. Other applicatorsmay be used provided their use results in an equivalent amountof cement being applied to the joining surfaces.7.5.3 Application of Primer an
42、d CementPVC solventcement is fast drying, and therefore the cement shall be appliedas quickly as possible, consistent with good workmanship. Itmay be necessary for two workers to perform this operation forlarger sizes of pipe. Under conditions of high atmospherichumidity, quick application is import
43、ant to minimize conden-sation of moisture from the air on the cement surface. Thesurface temperature of the mating surfaces should not exceed110F (45C) at the time of assembly. In direct sunlight or inFIG. 5 Apparatus for Cutting PipeD2855 96 (2010)3ambient temperatures above 110F, the pipe surface
44、mayexceed 110F. The pipe temperature may be reduced byswabbing the surface to be cemented with clean wet ragsprovided the pipe is thoroughly dried before the primer andcement are applied.7.5.3.1 First apply primer to inside socket surface (see 7.5.2for applicator or brush size). Use a scrubbing moti
45、on to ensurepenetration. Repeated applications may be necessary (see Fig.9).7.5.3.2 Next, soften surface of male end of pipe, to beinserted into socket, to depth of fitting socket by uniformlyapplying a liberal coat of primer. Be sure entire surface is wellsoftened (dissolved) (see Fig. 10).7.5.3.3
46、Again, brush inside socket surface with primer; then,without delay, apply cement to pipe while the surfaces are stillwet with primer (see Fig. 11).7.5.3.4 Apply cement lightly but uniformly to inside ofsocket, taking care to keep excess cement out of socket. This isto prevent solvent damage to pipe
47、(see Fig. 12). Time isimportant at this stage. Apply a second coat of cement to thepipe end (see Fig. 11).7.5.4 Low-Temperature ApplicationAt temperatures be-low freezing, 32F (0C), solvents penetrate and soften thePVC surfaces more slowly than in warmer weather. For thisreason it is recommended tha
48、t testing be done on a piece ofFIG. 6 Chamfer and Deburring of Pipe EdgesFIG. 7 Pipe Entering Dry FittingFIG. 8 Cleaning of Pipe with Dry Cloth to Remove Foreign MatterFIG. 9 Application of Primer to Inside Socket SurfaceFIG. 10 Liberal Application of Primer to Soften Surface of End ofPipeD2855 96 (
49、2010)4scrap pipe of the same lot to determine if satisfactory penetra-tion of the surfaces can be achieved at the existing temperature.This test can be done by applying the primer, waiting a fewminutes and scraping the surface with a knife edge. If sufficientpenetration is achieved, some of the plastic surface of the pipeshould be soft enough to be removed. If sufficient penetrationis not achieved, even with multiple applications of primer, it isunlikely that a suitable joint will result.7.5.4.1 Individual scrape tests may be needed for pipes and
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