1、Designation: C828 11Standard Test Method forLow-Pressure Air Test of Vitrified Clay Pipe Lines1This standard is issued under the fixed designation C828; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A n
2、umber 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 test method defines procedures for testing vitrifi
3、edclay pipe lines, using low-pressure air, to demonstrate theintegrity of the installed line. Refer to Practice C12.1.2 This test method shall be performed on lines afterconnection laterals, if any, have been plugged and bracedadequately to withstand the test pressure, and after the trencheshave bee
4、n backfilled for a sufficient time to generate asignificant portion of the ultimate trench load on the pipe line.The time between completion of the backfill operation andlow-pressure air testing shall be determined by the approvingauthority.1.3 This test method may also be used as a preliminary test
5、,which enables the installer to demonstrate the condition of theline prior to backfill and further construction activities.1.4 This test method is suitable for testing gravity-flowsewer pipe constructed of vitrified clay or combinations of clayand other pipe materials.1.5 Terminology C896 is to be u
6、sed for clarification ofterminology in this test method.1.6 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 considered standard.1.7 This standard does not pu
7、rport 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.2. Referenced Documents2.1 ASTM Standards:2C
8、12 Practice for Installing Vitrified Clay Pipe LinesC1091 Test Method for Hydrostatic Infiltration Testing ofVitrified Clay Pipe LinesC896 Terminology Relating to Clay Products3. Summary of Test Method3.1 The section of the line to be tested is plugged.Air, at lowpressure, is introduced into the plu
9、gged line. The line passesthe test if the rate of air loss, as measured by pressure drop,does not exceed a specified amount in a specified time. Thismay be determined by the use of Table 1, or calculated by useof the formulas in Appendix X1.4. Hazards4.1 The low-pressure air test may be dangerous to
10、 personnelif, through lack of understanding or carelessness, a line isover-pressurized or plugs are installed improperly. It is ex-tremely important that the various plugs be installed so as toprevent the sudden expulsion of a poorly installed or partiallyinflated plug. As an example of the hazard,
11、a force of 250 lbf(1110 N) is exerted on an 8-in. (205-mm) plug by an internalpressure of 5 psi (35 kPa). Observe the following safetyprecautions:4.1.1 No one shall be allowed in the manholes during testingbecause of the hazards.4.1.2 Install all plugs securely.4.1.3 When lines are to be tested, it
12、may be necessary thatthe plugs be braced as an added safety factor.4.1.4 Do not over-pressurize the lines.5. Preparation of the Line5.1 Air may pass through the walls of dry pipe. A wettedinterior pipe surface is desirable and will produce moreconsistent test results. Usually moisture absorbed from
13、thebackfill is sufficient to cope with this situation. Where practi-cal, clean the line prior to testing to wet the pipe surface andeliminate debris.6. Procedure6.1 Determine the test time for the section of line to betested using Table 1 or Table X1.1 or the formulas inAppendixX1.6.2 Plug all openi
14、ngs in the test section.1This test method is under the jurisdiction ofASTM Committee C04 on VitrifiedClay Pipe and is the direct responsibility of Subcommittee C04.20 on Methods ofTest and Specifications.Current edition approved Jan. 1, 2011. Published January 2011. Originallyapproved in 1975. Last
15、previous edition approved in 2006 as C828 06. DOI:10.1520/C0828-11.2For 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 we
16、bsite.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.3 Add air until the internal pressure of the line is raised toapproximately 4.0 psi (28 kPa). After this pressure is reached,allow the pressure to stabilize. The pressure will n
17、ormally dropas the air temperature stabilizes. This usually takes 2 to 5 min,depending on the pipe size. The pressure should be reduced to3.5 psi (24 kPa) before starting the test.6.4 Start the test when the pressure is at 3.5 psi (24 kPa). Ifa 1 psi (6.9 kPa) drop does not occur within the test tim
18、e, theline has passed. If the pressure drop is more than 1 psi (6.9 kPa)during the test time, the line is presumed to have failed the test.If the line fails the test, segmental testing may be utilized solelyto determine the location of leaks, if any, but not for theacceptance test as required by thi
19、s section. (see X2.3.3.2.)NOTE 1Ground water above the pipe will reduce air loss. If thesection of line under test shows significant infiltration, the agency mayrequire an infiltration test. Refer to Test Method C1091.7. Test Time7.1 Table 1 shows the required test time, T, in minutes/100ft of pipe
20、for each nominal pipe size. Test times are for a1.0-psi (6.9-kPa) pressure drop from 3.5 to 2.5 psi (24 to 17kPa). Table 1 has been established using the formulas con-tained in the appendix.7.2 If the section of line to be tested includes more than onepipe size, calculate the test time for each size
21、 and add the testtimes to arrive at the total test time for the section.7.3 It is not necessary to hold the test for the whole periodwhen it is clearly evident that the rate of air loss is less than theallowable.8. Precision and Bias8.1 No information is presented about either precision orbias of th
22、is test since the results are not reported in aquantitative fashion.9. Keywords9.1 air test; clay pipe; pipe; pressure test; sewers; testing;test section; vitrified clay pipeAPPENDIXES(Nonmandatory Information)X1. FORMULAS AND ALLOWABLE AIR LOSS STANDARDS USED IN TEST METHOD C828X1.1 Calculate the r
23、equired test time at a given allowableair loss as follows:T 5 K 3D2LQX1.2 Calculate air loss with a timed pressure drop asfollows:Q 5 K 3D2LTX1.3 Symbols:D = nominal size, in. (mm),K = 0.371 3 103for inch-pound units,K = 0.534 3 107for S.I. units,L = length of line of one pipe size, ft (m),Q = air l
24、oss, ft3/min (m3/min), andT = time for pressure to drop 1.0 psi (6.9 kPa), min.X1.4 An appropriate allowable air loss, Q, in cubic feet perminute, has been established for each nominal pipe size. Basedon field experience, the Qs that have been selected will enabledetection of any significant leak. T
25、able X1.1 lists the Qestablished for each pipe size.TABLE 1 Minimum Test Time for Various Pipe SizesNominalPipe Size, in. (mm)T (time),min/100 ft(min/100 m)48 (1220) 8.54 (100) 0.3 (0.98)6 (150) 0.7 (2.3)8 (205) 1.2 (3.9)10 (255) 1.5 (4.9)12 (305) 1.8 (5.9)15 (380) 2.1 (6.9)18 (455) 2.4 (7.9)21 (535
26、) 3.0 (9.8)24 (610) 3.6 (11.8)27 (685) 4.2 (13.8)30 (760) 4.8 (15.7)33 (840) 5.4 (17.7)36 (915) 6.0 (19.7)39 (990) 6.6 (21.6)42 (1065) 7.3 (23.9)C828 112X2. APPLICATION OF TEST METHOD C828X2.1 In order to demonstrate the technique of applying thistest method, the example in X2.2 has been prepared. I
27、t utilizesvarious pipe sizes, lengths, and conditions that may be encoun-tered in the field. The example has been designed to illustratethe use of Table 1 and the formulas.X2.2 ExampleAn installation has been made that consistsof line 1: 300 ft (92 m) of 15-in. (380-mm) vitrified clay pipewith no la
28、terals, and line 2: a reach of 350 ft (105 m) of 8-in.(205-mm) of vitrified clay pipe to which are attached 120 ft (37m) of 4 in. (100-mm) laterals of vitrified clay pipe.X2.2.1 ProblemWhat are the appropriate test times to usein order to demonstrate the integrity of the installed lines?X2.3 Solutio
29、ns:X2.3.1 What is the appropriate test time, T, for line 1?X2.3.1.1 Use Table 1, find time, T = 2.1 min/100 ft (31 m),for 15-in. (380-mm) pipe.T155 300 32.11005 6.3 minX2.3.2 What is appropriate time for line 2?X2.3.2.1 SolutionUse Table 1.T85 350 31.21005 4.2 minT45 120 30.31005 0.4 minTotal test t
30、ime 4.6 minX2.3.3 If further analysis is desired, the following exampleis provided:X2.3.3.1 If in the test of line 1, the 1.0-psi (6.9-kPa)pressure drop occurs in 3.3 min instead of 6.3 min, what is therate of air loss?Q 5 K 3D2LTwhere:Q 5 0.000371 31523 3003.35 7.6 ft3/min.This exceeds the 4 ft3/mi
31、n allowed in Table X1.1.X2.3.3.2 What further courses of action might be consid-ered in resolving this excess rate of air loss?(1) Segmentally test the line and compare the time-air lossvalues in each segment.(2) If the values in each segment are comparable, theair-loss problem may be distributed th
32、roughout the line, andfurther analysis should be made.(3) If the values in each segment are significantly different,each segment may be evaluated and further analysis be made inorder to determine the location of any significant air losses.ASTM International takes no position respecting the validity
33、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 standard is subject t
34、o 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 International Headquarters.
35、 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.This standard is
36、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 serviceast
37、m.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/).TABLE X1.1 Allowable Air Loss for Various Pipe SizesNominal,Pipe Size, in. (mm)Q,ft3/min (m3/min)48 (1220) 10.04 (100) 2.0 (0.06)6 (150) 2.0 (0.06)8 (205) 2.0 (0.06)10 (255) 2.5 (0.07)12 (305) 3.0 (0.08)15 (380) 4.0 (0.11)18 (455) 5.0 (0.14)21 (535) 5.5 (0.16)24 (610) 6.0 (0.17)27 (685) 6.5 (0.18)30 (760) 7.0 (0.20)33 (840) 7.5 (0.21)36 (915) 8.0 (0.23)39 (990) 8.5 (0.24)42 (1065) 9.0 (0.26)C828 113
