1、Designation: C 668 98 (Reapproved 2008)Standard Specification forAsbestos-Cement Transmission Pipe1This standard is issued under the fixed designation C 668; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. 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 Defense.1. Scope1.1 This specification covers asbestos-cement transmis
3、sionpipe intended for use in transmission systems that carry fluidsunder pressure. A transmission system consists of pipe lineswhich convey fluids from their source to a point of distributionor discharge. The system is characterized by relatively steadyflow and few appurtenances, thereby permitting
4、reasonablehydraulic analysis, including surge analysis.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.NOTE 1This specification is issued for product standardization andpurchasing purposes only, and does not include require
5、ments for instal-lation or the relationships between operating conditions and the strengthcharacteristics of the various classifications of pipe. The purchaser iscautioned that he must correlate installation and operating conditions withthe specified characteristics of the pipe.1.3 WarningBreathing
6、of asbestos dust is hazardous.Asbestos and asbestos products present demonstrated healthrisks for users and for those with whom they come into contact.In addition to other precautions, when working with asbestos-cement products, minimize the dust that results. For informa-tion on the safe use of chr
7、ysoltile asbestos, refer to “Safe Useof Chrysotile Asbestos: A Manual on Preventive and ControlMeasures.”21.4 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 an
8、d health practices and determine the applica-bility of regulatory limitations prior to use. See 1.3 for aspecific hazard warning.2. Referenced Documents2.1 ASTM Standards:3C 150 Specification for Portland CementC 458 Test Method for Organic Fiber Content of Asbestos-Cement ProductsC 500 Test Methods
9、 for Asbestos-Cement PipeC 595 Specification for Blended Hydraulic CementsC 618 Specification for Coal Fly Ash and Raw or CalcinedNatural Pozzolan for Use in ConcreteD 1869 Specification for Rubber Rings for Asbestos-Cement PipeD 2946 Terminology for Asbestos and AsbestosCementProducts2.2 Federal St
10、andard:Fed. Std. No. 123 Marking for Shipment (Civil Agencies)42.3 Military Standard:MIL-STD-129 Marking for Shipment and Storage42.4 Other Standards:Uniform Freight Classification Rules5National Motor Freight Classification Rules63. Terminology3.1 Definitions:3.1.1 couplingfitting made from larger
11、diameter pipe ofthe same type and class, or of Type II and a higher class forjoining asbestos-cement pipe that, when properly installed withthe proper accessories, develops a joint equivalent in strengthand serviceability to the pipe sections.3.1.2 lot, nfor pipe sizes 525 mm (21 in.) in diameter an
12、dsmaller, each 300 lengths of pipe or less, of identical class andsize manufactured on each machine during a 24-h period. Forpipe larger than 525 mm (21 in.), each 300 lengths of pipe or1This specification is under the jurisdiction of ASTM Committee C17 onFiber-Reinforced Cement Products and is the
13、direct responsibility of C17.03 onAsbestos - Cement Sheet Products and Accessories.Current edition approved May 1, 2008. Published July 2008. Originally approvedin 1970. Last previous edition approved in 2003 as C 668 98 (2003)2.2Available from The Asbestos Institute, http:/ referenced ASTM standard
14、s, 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.4Available from Standardization Documents Order Desk, Bldg. 4, Section D,700 Robbins Ave.,
15、 Philadelphia, PA 19111-5094 Attn: NPODS.5Available from the Uniform Classification Commission, Room 1106, 222 S.Riverside Plaza, Chicago, IL 60606.6Available from National Motor Freight Inc., 1616 “P” St., NW, Washington,DC 20036.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, We
16、st Conshohocken, PA 19428-2959, United States.less, of identical class and size manufactured on each machineduring a period of consecutive working days not exceedingseven days.3.1.3 Additional terminology is given in TerminologyD 2946.4. Classification4.1 Asbestos-cement pipe furnished under this sp
17、ecificationshall be manufactured in Classifications 21, 24, 28, 31, 34, 41,58, 55, and 62. Note that these numbers correspond to ten timesthe minimum hydrostatic strength, in MPa (30, 35, 40, 45, 50,60, 70, 80, and 90. This classification corresponds to one tenthof the minimum hydrostatic strength,
18、in psi).4.2 The types of pipe shall be known as Type I and Type IIcorresponding to the chemical requirements in 7.1.NOTE 2To assist the purchaser in choosing the type of pipe mostsuitable for his use, guidelines for the definition of aggressiveness of waterand of soil environments for selection of t
19、he proper type of asbestos-cement pipe are covered in Sections 19 to 25 of Test Methods C 500.5. Manufacture5.1 Asbestos-cement furnished under this specification shallbe composed of an intimate mixture of portland cement,conforming to Specification C 150, or portland slag or poz-zolan cements confo
20、rming to Specification C 595, and asbestosfiber with or without finely divided silica or silica-containingmineral additives conforming to Specification C 618 that canreact to form calcium silicate reaction products, and asbestosfiber. The mixture shall not contain more than 0.2 % ofnon-deleterious o
21、rganic components, as determined by TestMethod C 458. The material shall be of laminar constructionformed under pressure to a homogeneous structure and cured tomeet the physical and chemical requirements of this specifica-tion.6. Rubber Rings6.1 The rubber rings used to seal the joints of the asbest
22、os-cement pipe shall conform to the requirements of SpecificationD 1869.7. Chemical Requirements7.1 When uncombined calcium hydroxide tests are re-quested, one sample shall be taken from each lot of pipe andtested in accordance with Test Methods C 500. The sample tobe tested may be taken from one of
23、 the specimens selected forthe crushing test. The amount of uncombined calcium hydrox-ide shall not exceed 1 % for Type II pipe.NOTE 3There are no chemical requirements for Type I pipe.8. Hydrostatic Strength8.1 Each standard, random, or short length of pipe (seeSection 11) and each coupling sleeve,
24、 manufactured from thesame material as the pipe, shall be hydrostatically tested by themanufacturer prior to shipment and shall have sufficientstrength to withstand the internal hydrostatic pressure pre-scribed in Table 1, when tested in accordance with TestMethods C 500.8.2 From each lot of pipe wh
25、ich has passed the routinehydrostatic proof test, one length shall be selected by theinspector. A 30 cm (12 in.) or longer section of pipe cut froman unmachined portion of the selected length shall have theminimum hydrostatic strength designated in Table 2, whentested in accordance with Test Methods
26、 C 500, except that thepressure need not be held for 5 s.9. Flexural Strength9.1 Each length of pipe in sizes 15 and 20 cm (6 and 8 in.)nominal diameter having lengths 30 cm (12 in.) or longer shallhave sufficient flexural strength to withstand without failure thetotal load prescribed in Table 3 whe
27、n tested in accordance withTest Methods C 500.10. Crushing Strength10.1 From each lot, one length shall be selected by theinspector. A 30 cm (1 ft) section of pipe cut from anunmachined portion of the selected length shall have theminimum crushing strength prescribed in Table 4 and Table 5TABLE 1 Ap
28、plied Hydrostatic Proof PressuresAPipe Classification Applied Hydrostatic Pressure10 3 MPa rating (110 psi rating) MPa (psi)21 (30) 1.55 (225)24 (35) 1.81 (262)28 (40) 2.07 (300)31 (45) 2.32 (337)34 (50) 2.58 (375)41 (60) 3.10 (450)48 (70) 3.62 (525)55 (80) 4.13 (600)62 (90) 4.65 (675)AThe pressures
29、 and classifications indicated apply to all sizes.TABLE 2 Minimum Hydrostatic StrengthAPipe Classification Hydrostatic Pressure Rating10 3 MPa rating (110 psi rating) MPa (psi)21 (30) 2.1 (300)24 (35) 2.4 (350)28 (40) 2.8 (400)31 (45) 3.1 (450)34 (50) 3.4 (500)41 (60) 4.1 (600)48 (70) 4.8 (700)55 (8
30、0) 5.5 (800)62 (90) 6.2 (900)AThe pressures and classifications indicated apply to all sizes.TABLE 3 Minimum Applied Flexural Proof LoadsPipe Classification Nominal Size10 3 MParating(110 psirating)15 cm (6 in.) 20 cm (8 in.)kN (lbf) kN (lbf)21 (30) 16 (3700)24 (35) 20 (4400)28 (40) 10 (2300) 23 (51
31、00)31 (45) 11 (2500) 25 (5700)34 (50) 12 (2800) 28 (6400)41 (60) 14 (3200) 31 (6900)48 (70) 16 (3700) 34 (7600)55 (80) 18 (4000) 39 (8800)62 (90) 22 (4900) 45 (10100)C 668 98 (2008)2when tested in accordance with Test Methods C 500,VeeShaped Three Edge Bearing Method. (Warning see 1.3.)11. Dimension
32、s, Mass, and Permissible Variations11.1 Couplings and coupling areas of pipe shall be ma-chined or otherwise finished to such dimensions as will providetight joints when assembled with the proper accessories and putinto service for which the pipe is intended.11.2 Pipe shall be manufactured with nomi
33、nal inside diam-eters of 15, 20, 25, 30, 35, 38, 41, 46, 51, 53, 61, 69, 76, 84,91, 99, and 107 cm (6, 8, 10, 12, 14, 15, 16, 18, 20, 21, 24, 27,30, 33, 36, 39, and 42 in.) in the classifications defined in 4.1except 15 cm (6 in.) diameter pipe shall be of Classification 40through 90 only. The avera
34、ge diameters of standard andrandom lengths may be less than the nominal inside diameterby not more than 5 %, when measured approximately 75 mm(3 in.) from the end.11.3 The standard length shall be 4 m 6 25 mm (13 ft 6 1in.). Alternative standard lengths shall be 3 m 6 25 mm (10 ft6 1 in.) for 15-cm
35、(6-in.) pipe and 5 m 6 25 mm (16 ft 6 1in.) for 36-cm (14-in.) and larger pipe.At least 85 % of the totalfootage of pipe of any one classification, type, and size,excluding short lengths, shall be furnished in standard lengths.The remaining 15 % may be in random lengths of not less than2 m (7 ft). S
36、hort lengths, when specifically ordered, shall notexceed 2 m (6.75 ft).12. Workmanship and Finish12.1 Machined ends of the pipe that receive the couplingshall be free of dents and gouges that will affect the tightnessof the joint.12.2 Each pipe shall be free of bulges, dents, and tears in theinside
37、surface that result in a variation in diameter of more than5 mm (0.2 in.) from that obtained on adjacent unaffectedportions of the surface.13. Sampling13.1 All samples shall be in a normal air-dried condition inequilibrium with the atmospheric moisture when tests areinitiated.14. Inspection and Reje
38、ction14.1 All material furnished under this specification shallconform to the requirements stated herein and shall be sub-jected to the factory inspection and tests prescribed in thisspecification. When requested by the purchaser in his order(seeAppendix X1), the manufacturer shall notify the purcha
39、serof the time that the inspection and testing will take place so thatthe purchaser may arrange for witnessing such tests andinspections at his own expense. Instead of such inspection,when requested, the manufacturer shall be prepared to certifythat his product conforms to the requirements of this s
40、pecifi-cation.14.2 Pipe and couplings shall be inspected by the manufac-turer, before shipment, for compliance with the standards fordimensions, and workmanship, and finish (see also Sections7-10).14.3 Failure of any specimen tested for crushing strength towithstand 75 % of the load specified in Sec
41、tion 10 shall because for rejection of the lot from which the test specimen wastaken. When any specimen tested for crushing strength with-stands over 75 % but under 100 % of the load specified inSection 10, one specimen shall be cut from each of twoadditional pipes of the same lot. Failure of either
42、 of theseadditional specimens to meet the strength requirements ofSection 10 shall be cause for rejection of the entire lot fromwhich the original sample was taken.14.4 If any pipe subjected to the hydrostatic strength testdescribed in 8.2 fails to withstand the pressure specified, twoadditional len
43、gths of the same size and classification shall beselected from the pipe manufactured during the same shift andshall be subjected to the specified pressure. The failure of oneof these additional lengths to withstand the specified pressureshall be cause for rejection of the entire lot of that size and
44、classification manufactured during the same shift as the testlengths.TABLE 4 Minimum Crushing Strength, kN/linear, mNominalSizePipe Classificationcm (in.)10 3 MParating (0.1psi rating)21 24 28 31 34 41 48 55 62(30) (35) (40) (45) (50) (60) (70) (80) (90)15 6 35475869799813120 8 2935 4150587080108136
45、25 10 29 37 44 51 66 80 102 131 16130 12 29 37 44 58 76 93 114 146 17835 14 29 37 44 58 76 102 128 161 19738 15 34 41 48 63 80 108 136 175 21241 16 37 44 51 66 85 110 139 181 22546 18 37 44 58 73 95 124 161 204 26351 20 37 51 66 80 104 139 175 219 29253 21 37 51 66 85 107 142 182 234 30761 24 41 56
46、73 90 118 161 219 277 35069 27 51 61 80 102 128 182 241 299 39476 30 51 66 88 110 142 197 263 328 43884 33 51 73 95 117 153 212 285 358 48291 36 58 73 102 131 163 234 307 379 52599 39 61 77 110 142 175 251 328 409 569107 42 63 83 117 153 190 270 350 438 613TABLE 5 Minimum Crushing Strength, 100 lbf/
47、linear ftNominalSizePipe Classificationcm (in.)10 3 MParating (0.1psi rating)21(30)24(35)28(40)31(45)34(50)41(60)48(70)55(80)62(90)15 6 24 32404754679020 8 202428 34404855749325 10 20 25 30 35 45 55 70 90 11030 12 20 25 30 40 52 64 78 100 12235 14 20 25 30 40 52 70 88 110 13538 15 23 28 33 43 55 74
48、93 120 14541 16 25 30 35 45 58 75 95 124 15446 18 25 30 40 50 65 85 110 140 18051 20 25 35 45 55 71 95 120 150 20053 21 25 35 45 58 73 97 125 160 21061 24 28 38 50 62 81 110 150 190 24069 27 35 42 55 70 88 125 165 205 27076 30 35 45 60 75 97 135 180 225 30084 33 35 50 65 80 105 145 195 245 33091 36
49、40 50 70 90 112 160 210 260 36099 39 42 53 75 97 120 172 225 280 390107 42 43 57 80 105 130 185 240 300 420C 668 98 (2008)314.5 If the results of the uncombined calcium hydroxide testshows that the sample failed to meet the specification require-ments, two additional specimens shall be selected and sampledfor test. The failure of one of these two additional samples tomeet the specification requirements of Section 7 shall be causefor rejection of the lot.15. Marking and Shipping15.1 Each standard and random lengt
