1、Designation: C 828 06Standard Test Method forLow-Pressure Air Test of Vitrified Clay Pipe Lines1This standard is issued under the fixed designation C 828; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、 number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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 vitr
3、ifiedclay pipe lines, using low-pressure air, to demonstrate theintegrity of the installed line. Refer to Practice C 12.1.2 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
4、 been 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
5、test,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 C 896 is to
6、 be used for clarification ofterminology in this test method.1.6 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation only.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use.
7、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:2C12 Practice for Installing Vitrified Clay Pipe LinesC 1091 Test Method for Hy
8、drostatic Infiltration Testing ofVitrified Clay Pipe LinesC 896 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 plugged line. The line passesthe test if the rate of air loss, as measured by
9、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 personnelif, through lack of understanding or carelessness, a line isover-
10、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, a force of 250 lbf(1110 N) is exerted on an 8-in. (205-mm) plug by an inter
11、nalpressure 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 may be necessary thatthe plugs be braced as an added safety factor.4.1.4 Do
12、 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 thebackfill is sufficient to cope with this situation. Where practi-cal, cl
13、ean 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 openings in the test section.1This test method is under the jurisdiction ofASTM
14、Committee C04 on VitrifiedClay Pipe and is the direct responsibility of Subcommittee C04.20 on Methods ofTest and Specifications.Current edition approved Sept. 1, 2006. Published October 2006. Originallyapproved in 1975. Last previous edition approved in 2003 as C 828 03.2For referenced ASTM standar
15、ds, 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA
16、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 normally dropas the air temperature stabilizes. This usually takes 2 to 5 min,depending on the p
17、ipe 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 time, theline has passed. If the pressure drop is more than 1 psi (6.9 kPa)during the test time, t
18、he 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 this section. (see X2.3.3.2.)NOTE 1Ground water above the pipe will reduce air loss. If thesection
19、 of line under test shows significant infiltration, the agency mayrequire an infiltration test. Refer to Test Method C 1091.7. Test Time7.1 Table 1 shows the required test time, T, in minutes/100ft of pipe for each nominal pipe size. Test times are for a1.0-psi (6.9-kPa) pressure drop from 3.5 to 2.
20、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 and add the testtimes to arrive at the total test time for the section.7.3 It is not necessar
21、y to hold the test for the whole periodwhen it is clearly evident that the rate of air loss is less than theallowable.8. Keywords8.1 air test; clay pipe; pipe; pressure test; sewers; testing;test section; vitrified clay pipeAPPENDIXES(Nonmandatory Information)X1. FORMULAS AND ALLOWABLE AIR LOSS STAN
22、DARDS USED IN TEST METHOD C 828X1.1 Calculate the required 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
23、= length of line of one pipe size, ft (m),Q = air loss, 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 selec
24、ted will enabledetection of any significant leak. Table 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
25、.8 (5.9)15 (380) 2.1 (6.9)18 (455) 2.4 (7.9)21 (535) 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)TABLE X1.1 Allowable Air Loss for Various Pipe SizesNominal,Pipe Size, in. (mm)Q,ft3/min (m3/min)48 (122
26、0) 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)C828062X2.
27、 APPLICATION OF TEST METHOD C 828X2.1 In order to demonstrate the technique of applying thistest method, the example in X2.2 has been prepared. It 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
28、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 laterals, 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 vitr
29、ified clay pipe.X2.2.1 ProblemWhat are the appropriate test times to usein order to demonstrate the integrity of the installed lines?X2.3 Solutions: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.
30、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 time 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 oc
31、curs 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/min 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 lin
32、e and compare the time-air lossvalues in each segment.(2) If the values in each segment are comparable, theair-loss problem may be distributed throughout the line, andfurther analysis should be made.(3) If the values in each segment are significantly different,each segment may be evaluated and furth
33、er analysis be made inorder to determine the location of any significant air losses.ASTM International takes no position respecting 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
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36、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 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).C828063
