AASHTO M 274:87(2017) Standard Specification for Steel Sheet, Aluminum-Coated (Type 2), for Corrugated Steel Pipe.
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 available to the fabricator and purchaser on 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 properties 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 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 prepared and tested in accordance with the method specified in ASTM A463/A463M.
9.4. Mass of coating——Sampling for mass of coating shall be as prescribed in ASTM A463/A463M. The mass of coating shall be determined according to T213M/T213.
9.4.1. The mass may be converted from the sum of readings of both surfaces of the sheet by a magnetic thickness gauge suitably checked and demonstrated fbr accuracy (Note 4) (1 un = 3.2 g/rn2 each surface). When a magnetic thickness gauge is used and a dispute arises, the mass shall be determined by the stripping test in T 21 3M/T 213.
Note 4—Several magnetic and electromagnetic 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 method, according to ASTM A754/A754M. When this method is used and a dispute arises, the mass shall be determined by the stripping test in T213M/T213.
10. REJECTION
10.1. Material tested by the purchaser and found not conforming to this specification may be rejected.
11. CERTIFICATION
11 .1. When specified in the purchase order or contract, a manufacturer’s 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 found 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.AASHTO M 274 pdf download.