1、Standard Specification for Steel Sheet, Aluminum-Coated (Type 2), for Corrugated Steel Pipe AASHTO Designation: M 274-87 (2012) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-4b M 274-1 AASHTO Standard Specificati
2、on for Steel Sheet, Aluminum-Coated (Type 2), for Corrugated Steel Pipe AASHTO Designation: M 274-87 (2012) 1. SCOPE 1.1. This specification covers steel sheet used in the fabrication of corrugated steel pipe (CSP) used for drainage pipe and underdrains. The steel sheet is coated with commercially p
3、ure aluminum (referred to as Type 2) on continuous lines by the hot-dip process, and is produced in one coating mass only. The material is furnished flat in coils and cut lengths, and corrugated in cut lengths. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standard: T 213M/T 213, Mass Weight of Coating on Alu
4、minum-Coated Iron or Steel Articles 2.2. ASTM Standards: A463/A463M, Standard Specification for Steel Sheet, Aluminum-Coated, by the Hot-Dip Process A754/A754M, Standard Test Method for Coating Weight (Mass) of Metallic Coatings on Steel by X-Ray Fluorescence E376, Standard Practice for Measuring Co
5、ating Thickness by Magnetic-Field or Eddy-Current (Electromagnetic) Testing Methods 3. TERMINOLOGY 3.1. In this specification, manufacturer refers to the producer of the sheet, fabricator refers to the producer of the pipe, and purchaser refers to the purchaser of the finished pipe. 4. ORDERING INFO
6、RMATION 4.1. All sheet covered by this specification shall be ordered only to the specified thicknesses listed in Table 5. 4.2. Unless otherwise specified in the purchase order, all material furnished to this specification will be chemically treated, dry or oiled. 4.3. Orders for material to this sp
7、ecification shall include the following information, as necessary, to adequately describe the desired product: 4.3.1. Name of material (aluminum-coated steel sheet for CSP); 4.3.2. AASHTO designation number and date of issue; 2015 by the American Association of State Highway and Transportation Offic
8、ials.All rights reserved. Duplication is a violation of applicable law.TS-4b M 274-2 AASHTO 4.3.3. Corrugation size, if corrugated (Section 8.3); 4.3.4. Dimensions (thickness; width, either flat or overall corrugated; and length, if cut length); 4.3.5. Coil size requirements (specify maximum outside
9、 diameter (OD), acceptable inside diameter (ID), and maximum mass); 4.3.6. Certification, if required (Section 11.1); and 4.3.7. Special Requirements. Note 1Typical ordering descriptions are as follows: Aluminum-coated steel sheet for CSP conforming to M 274-_, 68-by-13-mm corrugations, 1.63 by 648
10、by 1500 m. Aluminum-coated steel sheet for CSP conforming to M 274-_, 2.01-by-699-mm coil, 1200-mm OD, 600-mm ID, 9000 kg max mass certified with test report. 5. GENERAL REQUIREMENTS 5.1. Steel sheet material supplied under this specification shall meet the applicable requirements of ASTM A463/A463M
11、 unless otherwise specified herein. ASTM A463/A463M applies to aluminum-coated sheet; however, tolerances, sampling, sample preparation, and methods of testing (except for mass of coating) all are applicable to aluminum-coated sheet. 6. CHEMICAL COMPOSITION 6.1. The base metal composition shall conf
12、orm to the requirements of Table 1. Table 1Base Metal Chemical Composition by Cast Analysis Composition, % Tolerance over the Max Limit by Product Analysis, % Sulfur, max 0.05 +0.01 Sum of carbon, manganese, phosphorus, silicon, and sulfur, max 0.70 +0.04 6.2. Aluminum Bath AnalysisThe bath shall be
13、 produced from commercially pure aluminum and the bath analysis shall conform to the limits given in Table 2. Table 2Aluminum Bath Analysis Composition, % Iron, max 3.0 Silicon, max 0.35 Magnesium, max 0.50 Othereach max 0.05 Othertotal max 0.20 2015 by the American Association of State Highway and
14、Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4b M 274-3 AASHTO 7. PHYSICAL PROPERTIES 7.1. The aluminum-coated steel sheet shall conform to the mechanical properties shown in Table 3, when tested prior to corrugating or other fabrication. Table 3Mecha
15、nical Requirements (Properties of Flat Material Prior to Fabrication) Tensile strength, min, MPa 310 Yield point, min, MPa 230 Elongation in 50 mm, min, % 20 Note 2Steel sheet tested after corrugating and other fabricating should conform to the tensile and yield strength requirements in Table 3, but
16、 due to cold working, conformance to the elongation requirement may not be obtained. 7.2. The mass of aluminum coating shall conform to the requirements prescribed in Table 4. The mass of coating is the total amount on both surfaces of the sheet expressed in g/m2of sheet. Table 4Mass of Coating Min
17、Check Limit Triple-Spot Test, g/m2Min Check Limit Single-Spot Test, g/m2300 270 7.3. Adherence of coating shall be such that no peeling occurs while the material is being corrugated and formed into pipe. 8. DIMENSIONS AND TOLERANCES 8.1. Sheet thickness shall conform to dimensions prescribed in Tabl
18、e 5. The thickness of the sheet includes both the base steel and the aluminum coating. Table 5Sheet Thicknessa Specified Thickness, mm Min Thickness, mm 1.32 1.17 1.63 1.45 2.01 1.83 2.77 2.57 3.51 3.28 aThickness is measured at any point on the sheet not less than 10 mm from an edge, and if corruga
19、ted, on the tangents of corrugation. 8.2. Permissible variations in width, length, and camber of flat material shall be in accordance with ASTM A463/A463M. Flatness tolerances of uncorrugated sheet shall conform to the dimensions prescribed in Table 6. 2015 by the American Association of State Highw
20、ay and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4b M 274-4 AASHTO Table 6Flatness Tolerances (Cut Lengths Only) Specified Thickness, mm Specified Width, mm Flatness Tolerance (Max Deviation from a Horizontal Flat Surface), mm 1.32 To 900 incl 12.7
21、 More than 900 to 1500 incl 19 1.63 and thicker To 1500 incl 12.7 Note: This table also applies to sheets cut to length from coils by the user when adequate flattening measures are performed. 8.3. Corrugations shall form smooth continuous curves and tangents. The dimensions of the corrugations shall
22、 be in accordance with Table 7 (Note 3). Table 7Corrugated Requirements Nominal Size, mm Max Pitch,a mm Min Depth,bmm Inside Radius Nominal, mm Min, mm 38 by 6.5 48 6 7 6.5 68 by 13 73 12 17 12 75 by 25 83 24 14 12 125 by 25 135 24 40 36 aPitch is measured from crest to crest of corrugation, at 90 d
23、egrees to the direction of the corrugations. bDepth is measured as the vertical distance from a straightedge resting on the corrugation crests to the bottom of the intervening valley. Note 3Some sizes of corrugations shown in Table 7 may not be available in cut-length sheets. The 38-by-6.5-mm size,
24、especially, is generally used only for helically corrugated pipe. 8.4. Covering width of corrugated sheet shall be in accordance with Table 8. Covering width is the distance between the crests of the extreme corrugations. There is no established tolerance for overall width since the covering width a
25、nd lip dimensions are the governing factors for the formed product. The lip dimension of corrugated sheets shall be in accordance with Table 9. This dimension is measured along the radial curvature from the crest of the corrugation to the edge of the sheet. Table 8Covering Width Tolerance for Corrug
26、ated Sheet Covering Width, mm Tolerance Over and Under, mm To 600 incl 6.4 Over 600 to 900 incl 9.5 Over 900 to 1200 incl 12.7 Table 9Corrugated Sheet Lip Dimensions Nominal Corrugation Size, mm For Riveted Pipe Construction,amm For Spot Welded Pipe Construction, Min, mm 68 by 13 19 11 75 by 25 22 1
27、3 125 by 25 22 13 aTolerances, +4.8 mm, 0. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4b M 274-5 AASHTO 9. SAMPLING AND TESTING 9.1. Except as specified below, the manufacturer shall make adequat
28、e tests and measurements to ensure that the material produced complies with this specification. 9.1.1. Test results, including chemical composition, mechanical properties, and mass of coating for each heat and coating lot, shall be maintained by the sheet manufacturer for 7 years and shall be made a
29、vailable to the fabricator and purchaser upon request. 9.2. The purchaser of the sheet (fabricator), or purchaser of the pipe made from the sheet, may make such tests as deemed necessary to determine the acceptability of the material or to verify the correctness of a certification. 9.3. Mechanical p
30、roperties shall be determined on sheet prior to corrugating or other fabricating, except tests may be made after fabrication by the purchaser for tensile strength and yield point. 9.3.1. Two tension tests shall be made on random samples of finished material from each cast or heat. When the finished
31、material from said cast or heat is less than 45 Mg, one test is sufficient. When material rolled from one cast or heat differs 1.27 mm or more in thickness, one tension test shall be made from both the thickest and thinnest material rolled regardless of the mass represented. The samples shall be pre
32、pared and tested in accordance with the method specified in ASTM A463/A463M. 9.4. Mass of CoatingSampling for mass of coating shall be as prescribed in ASTM A463/A463M. The mass of coating shall be determined according to T 213M/T 213. 9.4.1. The mass may be converted from the sum of readings of bot
33、h surfaces of the sheet by a magnetic thickness gauge suitably checked and demonstrated for accuracy (Note 4) (1 m = 3.2 g/m2each surface). When a magnetic thickness gauge is used and a dispute arises, the mass shall be determined by the stripping test in T 213M/T 213. Note 4Several magnetic and ele
34、ctromagnetic types of coating thickness gauges are commercially available and are a satisfactory basis for acceptance when properly calibrated just prior to inspection use (see ASTM E376). 9.4.2. The mass of coating may be determined from the coating thickness measured by the x-ray fluorescence meth
35、od, according to ASTM A754/A754M. When this method is used and a dispute arises, the mass shall be determined by the stripping test in T 213M/T 213. 10. REJECTION 10.1. Material tested by the purchaser and found not conforming to this specification may be rejected. 11. CERTIFICATION 11.1. When speci
36、fied in the purchase order or contract, a manufacturers certification shall be furnished to the purchaser of the sheet (fabricator) or to the purchaser of the finished pipe stating that the material was manufactured, sampled, tested, and inspected in accordance with this specification and has been f
37、ound to meet the requirements for the material described in the purchase order or contract. When specified in the purchase order or contract, a report of the test results shall be furnished. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplicati
38、on is a violation of applicable law.TS-4b M 274-6 AASHTO 12. MARKING 12.1. Each 0.6 to 1.5 m of sheet in coils or cut lengths shall be identified by showing the following: 12.1.1. Name of sheet manufacturer, 12.1.2. Brand name, 12.1.3. Specified thickness, 12.1.4. Specified mass of coating, 12.1.5.
39、Identification symbols relating to a specific heat number and lot number, and 12.1.6. AASHTO designation number. 12.2. The brand shall be removed, obliterated, or rebranded “Non-Specification Material” on each 0.6 to 1.5 m of material in a lot or heat for which control tests do not show conformance to this specification. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.
