1、Designation: A 926 03 (Reapproved 2008)Standard Test Method forComparing the Abrasion Resistance of Coating Materials forCorrugated Metal Pipe1This standard is issued under the fixed designation A 926; the number immediately following the designation indicates the year oforiginal adoption or, in the
2、 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 test method covers a procedure for comparingmaterials used for coating, paving an
3、d lining corrugated metalpipe by use of a bed load abrasion testing machine. Theprocedure attempts to simulate the effect of stone, gravel andsand carried by a stream through corrugated metal pipe.1.2 The values stated in inch-pound units are to be regardedas standard. The SI units given in parenthe
4、ses are for informa-tion only.1.3 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 and health practices and determine the applica-bility of regulatory limitation
5、s prior to use.2. Referenced Documents2.1 ASTM Standards:2A 742/A 742M Specification for Steel Sheet, MetallicCoated and Polymer Precoated for Corrugated Steel PipeA 849 Specification for Post-Applied Coatings, Pavings,and Linings for Corrugated Steel Sewer and Drainage PipeA 929/A 929M Specificatio
6、n for Steel Sheet, Metallic-Coated by the Hot-Dip Process for Corrugated Steel PipeC 131 Test Method for Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact in the LosAngeles MachineC 136 Test Method for Sieve Analysis of Fine and CoarseAggregates3. Summary of Test Method
7、3.1 Curved steel panels, coated with the matter to beevaluated, are mounted on the inside surface of a cylindricaldrum. A charge of fine aggregate coarse aggregates and waterare added and the drum is sealed. Then the drum is rotated tocause an abrasive flow over the materials being tested. Afterthe
8、prescribed number of revolutions, the panels are removedfrom the drum, inspected and weighed for loss; or Alternative2 counting grid method is used.4. Significance and Use4.1 This test method provides a means of determining anabrasion rate (weight and calculated average thickness loss)when comparing
9、 materials, coatings, pavings, or linings undertest conditions that will be subjected to abrasive bed loads. Theimportance of this information is recognized when dealing withculverts, storm and sanitary sewer applications, although thelast two generally do not have the same degree of abrasion dueto
10、the flatter slopes and less bed loads than culverts. Specifi-cally, the invert of these types of pipe, regardless of thematerial used, can be exposed to flows containing abrasive bedloads or solid particulates that cause wearing of the pipe wall.4.2 By subjecting materials to wear in the bed load ab
11、rasionmachine with a controlled bed load charge made up of fineaggregate and coarse aggregate over a specified period, acomparison of the resistance between materials can be estab-lished.4.3 This test method does not simulate the effect of abrasivematerial striking the upstream face of corrugations,
12、 as wouldbe typical for coating materials which do not completely fill thecorrugations.NOTE 1Caution: This test method uses specific quantitative values toencourage repetitive results and does not consider varying bed loadcharacteristics, ratio of water to bed load, velocity, time or actual fieldcon
13、ditions, and the effect of exposed edges on laminates. The user mustuse extreme care in comparing one test result to another because of theseand other variables.1This test method is under the jurisdiction of ASTM Committee A05 onMetallic-Coated Iron and Steel Products and is the direct responsibilit
14、y ofSubcommittee A05.17 on Corrugated Steel Pipe Specifications.Current edition approved May 1, 2008. Published July 2008. Originally approvedin 1994. Last previous edition approved in 2003 as A 926 - 03.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Se
15、rvice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19
16、428-2959, United States.5. Apparatus5.1 Bed Load Abrasion Machine, equipped with a counterand conforming in all essential characteristics to the designshown in Fig. 1. The machine shall consist of a hollow steelcylinder, closed at both ends, having an outside diameter of 246 0.2 in. (610 6 5 mm). On
17、e closed end of the cylinder shallhave four bolted plexiglass windows one of which is elongatedto provide placement of the specimens. A shaft mountedhorizontal and through the cylinder shall have a drive pulley atone end and be supported by bearings connected to a frameallowing the cylinder to turn
18、freely and be in alignment with adrive motor below.5.2 The machine shall consistently rotate at 50 6 5 r/minwhen specimens are mounted and drum is fully charged.6. Test Specimens6.1 PanelsTest specimens shall consist of zinc-coatedsteel sheet with or without a nonmetallic protective coating tobe eva
19、luated. The steel sheet shall conform to SpecificationA 929/A 929M with a specified thickness of 0.064 in. (1.63mm). All panels are curved as shown in Fig. 2, with the testsurface concave. A plain zinc-coated panel serves as a controlspecimen.6.1.1 Panels to serve as a substrate for coating material
20、s tobe applied to fabricated pipe shall be curved prior to applica-tion of the coating material. The control panel and panelshaving factory applied nonmetallic coating (such as polymerprecoated sheet, Specification A 742/A 742M) shall be in theas-received condition.6.1.2 Fabricate the panels as show
21、n in Fig. 2. Take care infabricating panels with preapplied nonmetallic coatings toavoid damage to the coating. Curve the panels to a smooth,uniform radius with no straight tangent portions at the ends. Adevice as described in Appendix X1 shall be used.6.2 CoatingCoat the panels as recommended by th
22、emanufacturer of the coating material. The thickness of thecoating shall be equal to, or greater than, the minimumthickness proposed or required to be used on pipe (usually onthe crest of corrugations).6.3 MountingMount the coated test panels in the drumusing516 in. (or M8) steel bolts. Other sizes
23、of bolts may beused provided appropriate adjustments are made in the mount-ing hole slot. Use washers under the bolt head (or nut) toprotect the coating from damage when tightening the bolt (ornut). Place a thin foam cushion (expanded neoprene, etc.)under the panels to provide a tight fit against th
24、e drum and toFIG. 1 Bed Load Abrasion Testing MachineA 926 03 (2008)2keep fines from eroding the backside of the panel. Shims shallbe used as required under the test panels to maintain the sameheight between the surface of adjacent specimens and the drumwhen mounted.6.4 Panel WeightIn order to evalu
25、ate the effect of the test,determine the panel weight using a balance accurate to 0.01 g.6.4.1 Panel substrate prior to application of coating,6.4.2 Panel with the coating before test, and6.4.3 Panel with the coating after testing.6.4.4 Panels tested with factory applied coating do notpermit determi
26、nation of the weight as described in 6.4.1.Panels used as reference panels without non-metallic coatingrequire weighing before and after test.7. Procedure7.1 Mount three test specimens with coating, paving, orlining and one control specimen made of a panel with nocoating. Take care not to damage or
27、alter test specimens afterthey have been coated and weighed.7.2 ChargeThe charge shall consist of 7 lb (3.2 kg) ofaggregate and 35 lb (15.9 kg) of water having a pH of 7.0 60.5. The aggregate shall be 312 lb (1.6 kg) of38 in. (9.5 mm)to No. 4 coarse and 312 lb (1.6 kg) of fine (wash sand) gradedas i
28、n Table 1.7.2.1 Sieve the aggregate according to the procedure in TestMethod C 136 and recombine to obtain the grading in Table 1.7.2.2 For comparison of coatings performed by one agency,the aggregate may be from any source able to supply aconsistent product. The aggregate shall be a crushed rockhav
29、ing a loss in the Los Angeles test (see Test Method C 131)not greater than 20 %.7.2.3 For comparison of coatings performed by differentagencies, use either a reference aggregate (see Note 2)orestablish by comparison tests that the aggregate used by eachagency provides comparable results.NOTE 2The fo
30、llowing source has been used as a reference by someagencies: Bear River Aggregate, available from R. J. Miles Co., Corner ofRailroad and Oak, Colfax, CA.7.3 Alternative 1Perform the test in two segments withmeasurements being made at the conclusion of both. The firststopping shall be at 500,000 revo
31、lutions, approximately 6.95days or 166 h and 50 min and the second stopping shall be at1,000,000 revolutions, approximately 13.89 days or 333 h and20 min concluding the test. Inspection shall be done withcaution so as not to damage the samples or disturb the charge.7.3.1 During testing maintain the
32、ambient temperature at 68to 86F (20 to 30C).7.3.2 Upon completion of the test, wash, dry, weigh, pho-tograph, and log each sample.7.3.3 Make comparison between the weight of the coated,paved, or lined test specimen before the test and after.FIG. 2 Test PanelTABLE 1 Typical Grading AnalysisPercent Pa
33、ssingCoarse Aggregate Fine Aggregate (Wash Sand)Sieve Size Percent Passing Sieve Size Percent Passing12 in. (12.5 mm) 100 No. 4 (4.75 mm) 10038 in. (9.5 mm) 100 No. 8 (2.36 mm) 91No. 4 (4.75 mm) 14 No. 16 (1.18 mm) 71No. 8 (2.36 mm) 0 No. 30 (600 m) 42No. 50 (300 m) 11No. 100 (150 m) 2No. 200 (75 m)
34、 1A 926 03 (2008)37.4 Alternative 2Perform the test as Alternative 1 exceptthe charge shall be replaced with new material every 250 000revolutions and the test will continue until at least onespecimen has exceeded the limits of 7.4.1.7.4.1 An acrylic counting grid using 1 in. (25 mm) squares(6 in. (
35、152 mm) by 16 in. (407 mm) panel or 6 grid squares by16 grid squares totaling 96 grid squares) shall be used tomeasure performance. The number of grid squares showingexposed metal shall not exceed 10 grid squares of the total gridsquares.NOTE 3Certain coatings may coat the aggregate and affect the t
36、estresults.8. Report8.1 Prepare a report for each set of samples run, and reportthe following essential information:8.1.1 Color photographs of the sample taken before andafter the test,8.1.2 A complete identification of all four samples (Useroption is to include an IR fingerprint of the coating mate
37、rial).8.1.3 A complete description of the location of any visiblesurface flaws,8.1.4 The weight of each sample substrate after preparation(holes, etc.),8.1.5 The weight of samples after coating has been applied,8.1.6 The weight of samples after the specified number ofrevolutions have been completed,
38、8.1.7 The number of revolutions,8.1.8 Duration, days, hours and minutes of test,8.1.9 Notation of any deviation in test procedure from thatset forth in preceding paragraphs, that is, RPM at which testwas conducted, and8.1.10 When using Alternative 2 document the wear patternand number of grid square
39、s affected for each test specimen ateach charge change until at least one specimen has exceededthe limits of 7.4.1.8.1.11 Comments.9. Precision and Bias9.1 PrecisionThe precision of this test method has notbeen determined.9.2 BiasNo statement is being made about the bias of thistest method since the
40、re is no accepted reference materialsuitable for determining the bias of this procedure.10. Keywords10.1 abrasion resistance of pipe coatings; coatingsabrasion; corrugated metal pipe; resistance of coating materialsto abrasion; steel pipe coatingsAPPENDIX(Nonmandatory Information)X1. PANEL CURVING D
41、IEX1.1 Curving the uncoated, paved or lined zinc-coatedculvert sheet shall be accomplished by using the two partwooden die shown in Fig. X1.1 and a hydraulic press. Theradius of the die shall be 7 6 0.2 in. (175 6 5 mm) to allowfor springback. If materials to be curved do not meet therequirements of
42、 Section 6 the die radius must be altered toallow for a differing degree of springback to achieve the finalspecimen radius of curvature required.A 926 03 (2008)4SUMMARY OF CHANGESCommitteeA05 has identified the location of selected changes to this standard since the last issue (A 926 - 97)that may i
43、mpact the use of this standard.A 926 - 03:(1) Replaced reference to Specification A 444/A 444M with itsreplacement: Specification A 929/A 929.(2) Replaced “may” with “shall” in several instances.(3) Added text to Summary of Test Method for clarity.ASTM International takes no position respecting the
44、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 validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is
45、subject to 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 Head
46、quarters. 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 sta
47、ndard 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).FIG. X1.1 Wooden Two Part DieA 926 03 (2008)5