1、Designation: D2992 12D2992 18 An American National StandardStandard Practice forObtaining Hydrostatic or Pressure Design Basis for“Fiberglass” (Glass-Fiber-Reinforced Thermosetting-Resin)Pipe and Fittings1This standard is issued under the fixed designation D2992; the number immediately following the
2、 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. Scope*1.1 This practice establishe
3、s two procedures, Procedure A (cyclic) and Procedure B (static), for obtaining a hydrostatic designbasis (HDB) or a pressure design basis (PDB) for fiberglass piping products, by evaluating strength-regression data derived fromtesting pipe or fittings, or both, of the same materials and construction
4、, either separately or in assemblies. Both glass-fiber-reinforced thermosetting-resin pipe (RTRP) and glass-fiber-reinforced polymer mortar pipe (RPMP) are fiberglass pipe.NOTE 1For the purposes of this standard, polymer does not include natural polymers.1.2 This practice can be used for the HDB det
5、ermination for fiberglass pipe where the ratio of outside diameter to wall thicknessis 10:1 or more.NOTE 2This limitation, based on thin-wall pipe design theory, serves further to limit the application of this practice to internal pressures which, bythe hoop-stress equation, are approximately 20 % o
6、f the derived hydrostatic design stress (HDS). For example, if HDS is 5000 psi (34 500 kPa), the pipeis limited to about 1000-psig (6900-kPa) internal pressure, regardless of diameter.1.3 This practice provides a PDB for complex-shaped products or systems where complex stress fields seriously inhibi
7、t the useof hoop stress.1.4 Specimen end closures in the underlying test methods may be either restrained or free, leading to certain limitations.1.4.1 Restrained EndsSpecimens are stressed by internal pressure only in the hoop direction, and the HDB is applicable forstresses developed only in the h
8、oop direction.1.4.2 Free EndsSpecimens are stressed by internal pressure in both hoop and longitudinal directions, such that the hoop stressis twice as large as the longitudinal stress. This practice may not be applicable for evaluating stresses induced by loadings wherethe longitudinal stress excee
9、ds 50 % of the HDS.1.5 The values stated in inch-pound units are to be regarded as the standard. The values in parentheses are given for informationpurposes only.NOTE 3There is no known ISO equivalent to this standard.1.6 This standard does not purport to address all of the safety concerns, if any,
10、associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with inter
11、nationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D618 Pr
12、actice for Conditioning Plastics for TestingD883 Terminology Relating to Plastics1 This practice is under the jurisdiction ofASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.23 on Reinforced Plastic Piping Systemsand Chemical Equipment.Current edition approved April
13、 1, 2012May 15, 2018. Published May 2012May 2018. Originally approved in 1971. Last previous edition approved in 20062012 asD2992 06.D2992 12. DOI: 10.1520/D2992-12.10.1520/D2992-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.or
14、g. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit
15、may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at
16、the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D1598 Test Method for Time-to-Failure of Plastic Pipe Under Constant Internal PressureD1599 Test Method for Resistance to Short-Time Hydraulic Pressure of Plastic
17、 Pipe, Tubing, and FittingsD1600 Terminology for Abbreviated Terms Relating to PlasticsD2143 Test Method for Cyclic Pressure Strength of Reinforced, Thermosetting Plastic PipeD3567 Practice for Determining Dimensions of “Fiberglass” (Glass-Fiber-Reinforced Thermosetting Resin) Pipe and FittingsF412
18、Terminology Relating to Plastic Piping SystemsF948 Test Method for Time-to-Failure of Plastic Piping Systems and Components Under Constant Internal Pressure With Flow(Withdrawn 2018)32.2 ISO Standard:3 3 Preferred NumbersSeries of Preferred Numbers43. Terminology3.1 Definitions:3.1.1 GeneralDefiniti
19、ons are in accordance with Terminologies D883 and F412, and abbreviations are in accordance withTerminology D1600, unless otherwise indicated.3.1.2 closure, free-enda sealing device or mechanism fastened to the end of the test specimen so that internal pressureproduces longitudinal tensile stresses
20、in addition to hoop and radial stresses in the test specimen.3.1.3 closure, restrained-enda sealing device or mechanism which relies on a rod through the test specimen or an externalstructure to resist the end thrust produced by internal pressure, thereby limiting the stresses in (straight) specimen
21、s to the hoop andradial directions only.3.1.4 failurethe transmission of the test fluid through the body of the specimen in any manner, whether it be a wall fracture,localized leaking, or weeping at a distance greater than one diameter from the end closure.NOTE 4For this practice, specimens which ha
22、ve not failed may be included as failures under the specific conditions given in 6.3, 9.3, and 12.2.3.1.5 fiberglass pipea tubular product containing glass fiber reinforcement embedded in or surrounded by curedthermosetting-resin; the composite structure may contain aggregate, granular or platelet f
23、illers, thixotropic agents, pigments, ordyes; thermoplastic or thermosetting liners or coatings may be included.3.1.6 reinforced polymer mortar pipe (RPMP)a fiberglass pipe with aggregate.3.1.7 reinforced thermosetting resin pipe (RTRP)a fiberglass pipe without aggregate.3.1.8 hoop stressthe tensile
24、 stress in the wall of the piping product in the circumferential direction due to internal pressure;hoop stress will be calculated by the ISO equation, as follows:S 5PD2tr!/2tr (1)where:S = hoop stress, psi (kPa),D = average reinforced outside diameter, in. (mm),P = internal pressure, psig (kPa), an
25、dtr = minimum reinforced wall thickness, in. (mm).NOTE 5Hoop stress should only be determined on straight hollow cylindrical specimens. Product evaluation of more complex shapes may be basedon pressure.3.1.9 hydrostatic design basis (HDB)a hoop stress developed for fiberglass pipe by this practice a
26、nd multiplied by a servicedesign factor to obtain an HDS.3.1.10 hydrostatic design pressure (HDP)the estimated maximum internal hydrostatic pressure that can be applied cyclically(Procedure A) or continuously (Procedure B) to a piping component with a high degree of certainty that failure of the com
27、ponentwill not occur.3.1.11 hydrostatic design stress (HDS)the estimated maximum tensile stress in the wall of the pipe in the hoop direction dueto internal hydrostatic pressure that can be applied cyclically (Procedure A) or continuously (Procedure B) with a high degree ofcertainty that failure of
28、the pipe will not occur.3.1.12 long-term hydrostatic strength (LTHS)the estimated tensile stress in the wall of the pipe in the hoop direction due tointernal hydrostatic pressure that, when applied cyclically, will cause failure of the pipe after a specified number of cycles byProcedure A or a speci
29、fied number of hours by Procedure B.NOTE 6The time for determination of LTHS or LTHP is specified by the product standard. Typically, the time is 150 106 or 657 106 cycles forProcedure A and 100 000 or 438 000 h for Procedure B.3 The last approved version of this historical standard is referenced on
30、 www.astm.org.4 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.D2992 1823.1.13 long-term hydrostatic pressure (LTHP)the estimated internal pressure of the piping product that, when appliedcyclically, will cause failure o
31、f the product after a specified number of cycles by Procedure A or a specified number of hours byProcedure B.3.1.14 pressure design basis (PDB)an internal pressure developed for fiberglass piping product by this practice and multipliedby a service design factor to obtain an HDP.3.1.15 pressure ratin
32、g (PR)the estimated maximum pressure in the pipe or fitting that can be exerted continuously with a highdegree of certainty that failure of the piping component will not occur.3.1.16 service design factora number equal to 1.00 or less that takes into consideration all the variables and degree of saf
33、etyinvolved in a fiberglass piping installation so that when it is multiplied by the HDB, an HDS and corresponding pressure ratingis obtained, or when it is multiplied by the PDB, a pressure rating is obtained directly, such that in either case a satisfactory andsafe piping installation results when
34、 good quality components are used and the installation is made properly.3.2 Definitions of Terms Specific to This Standard:3.2.1 average outside diametera measurement obtained in accordance with Practice D3567 less any veil-reinforced andnonreinforced exterior coating thicknesses.3.2.2 minimum reinf
35、orced wall thicknessa measurement obtained in accordance with Practice D3567, excluding veil-reinforced and nonreinforced coating and lining thicknesses; wall thickness of fittings is determined at the thinnest section of thefitting body.4. Summary of Practice4.1 Procedure A consists of exposing a m
36、inimum of 18 specimens of pipe or fittings, or both to cyclic internal pressures at acycle rate of 25 cycles/min and at several different pressures. Elevated test temperatures are obtained by circulating a hot liquidthrough the specimens or by testing in an air environment where the temperature is c
37、ontrolled.4.1.1 The cyclic LTHS or cyclic LTHPof a pipe or fitting is obtained by an extrapolation of a log-log plot of the linear regressionline for hoop stress or internal pressure versus cycles to failure.4.1.2 The experimental basis for Procedure A shall be in accordance with Test Method D2143,
38、which forms a part of thispractice. When any part of the procedure is not in agreement with Test Method D2143, the provisions of this practice shall be used.4.1.3 Joints between pipe and fitting specimens shall be typical of those normally used for the kind of piping being tested.4.2 Procedure B con
39、sists of exposing a minimum of 18 specimens of pipe or fittings, or both, to constant internal hydrostaticpressures at differing pressure levels in a controlled environment and measuring the time to failure for each pressure level. Testtemperatures are obtained by immersing the specimens in a contro
40、lled-temperature water bath, by testing in an air environmentwhere the temperature is controlled, or by circulating a temperature-controlled fluid through the specimen.NOTE 7Testing in a water bath precludes the detection of weeping failure, (see 3.1.4) by either visual or electronic means.4.2.1 The
41、 static LTHS or static LTHP of a pipe or fitting is obtained by an extrapolation of a log-log linear regression line forhoop stress or internal pressure versus time to failure.4.2.2 The experimental basis for Procedure B shall be in accordance with either Test Method D1598 or Test Method F948, orbot
42、h, which form a part of this practice. When any part of this practice is not in agreement with the selected method, the provisionsof this practice shall be used.4.2.3 Joints between pipe and fitting specimens shall be typical of those normally used for the kind of piping being tested.4.3 The HDB cat
43、egory is obtained by categorizing the LTHS in accordance with Section 7 or Section 10.4.4 The PDB category is obtained by categorizing the LTHP in accordance with Section 8 or Section 11.4.5 Hydrostatic design stresses for pipe are obtained by multiplying the HDB values by a service design factor.4.
44、6 Reconfirmation of HDB or PDB for Altered ConstructionsWhen a product already has an HDB or PDB determined inaccordance with this practice and a change of process or material is made, a reconfirmation of the original HDB or PDB mayshallbe attempted in accordance with Section 12. At least six specim
45、ens must be tested and meet the specified criteria.5. Significance and Use5.1 This practice is useful for establishing the hoop stress or internal pressure versus time-to-failure relationships, under selectedinternal and external environments which simulate actual anticipated product end-use conditi
46、ons, from which a design basis forspecific piping products and materials can be obtained. This practice defines an HDB for material in straight, hollow cylindricalshapes where hoop stress can be easily calculated, and a PDB for fittings and joints where stresses are more complex.5.1.1 An alternative
47、 design practice based on initial strain versus time-to-failure relationships employs a strain basis HDBinstead of the stress basis HDB defined by this practice. The strain basis HDB is most often used for buried pipe designs withinternal pressures ranging from 0 to 250 psig (1.72 MPa).D2992 1835.2
48、To characterize fiberglass piping products, it is necessary to establish the stress versus cycles or time to failure, or pressureversus cycles or time to failure relationships over three or more logarithmic decades of time (cycles or hours) within controlledenvironmental parameters. Because of the n
49、ature of the test and specimens employed, no single line can adequately represent thedata. Therefore, the confidence limits shouldshall be established.5.3 Pressure ratings for piping of various dimensions at each temperature may be calculated using the HDS determined bytesting one size of piping provided that the same specific process and material are used both for test specimens and the piping inquestion.5.4 Pressure ratings at each temperature for components other than straight hollow shapes may be calculated using the HDPdetermined by test
