ASME SA-179-SA-179M:2021 pdf free download – Standard Specification for Seamless Cold-Drawn Low-Carbon Steel Heat-Exchanger and Condenser Tubes
1.1 This specification covers minimum-wall-thickness, seamless cold-drawn low-carbon steel tubes for tubular heat exchangers, condensers, and similar heat transfer apparatus.
1.2 This specification covers tubes 1 ⁄ 8 to 3 in. [3.2 to 76.2 mm], inclusive, in outside diameter. NOTE 1—Tubing smaller in outside diameter and having a thinner wall than indicated in this specification is available. Mechanical property requirements do not apply to tubing smaller than 1 ⁄ 8 in. [3.2 mm] in outside diameter or with a wall thickness under 0.015 in. [0.4 mm].
1.3 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently ofthe other. Combining values from the two systems may result in nonconformance with the specifi- cation. The inch-pound units shall apply unless the “M” designation of this specification is specified in the order.
9.1 When requested on the purchase order, a product analy- sis shall be made by the supplier from 1 tube per 250 pieces or when tubes are identified by heat, one tube per heat shall be analyzed. The chemical composition thus determined shall conform to the requirements specified.
9.2 If the original test for product analysis fails, retests of two additional billets or tubes shall be made. Both retests, for the elements in question, shall meet the requirements of the specification; otherwise all remaining material in the heat or lot (Note 2) shall be rejected or, at the option ofthe producer, each billet or tube may be individually tested for acceptance. Billets or tubes which do not meet the requirements of the specifica- tion shall be rejected.
10. Hardness Requirements
10.1 The tubes shall have a hardness number not exceeding 72 HRB.
11. Mechanical Tests Required
11.1 Flattening Test—One flattening test shall be made on specimens from each of two tubes from each lot (Note 2) or fraction thereof.
11.2 Flaring Test—One flaring test shall be made on speci- mens from each of two tubes from each lot (Note 2) or fraction thereof.
11.3 Flange Test—When specified as a substitute for the flaring test, for tubes having a wall thickness (actual mean wall) less than 10 % of the outside diameter, one test shall be made on specimens from each oftwo tubes from each lot (Note 2) or fraction thereof. For tubes other than specified above, the flange test shall not be required.
11.4 Hardness Test—Rockwell hardness tests shall be made on specimens from two tubes from each lot. The term lot applies to all tubes, prior to cutting, of the same nominal diameter and wall thickness which are produced from the same heat of steel. When final heat treatment is in a batch-type furnace, a lot shall include only those tubes of the same size and the same heat which are heat treated in the same furnace charge. When the final heat treatment is in a continuous furnace, a lot shall include all tubes of the same size and heat, heat treated in the same furnace at the same temperature, time at heat, and furnace speed.
11.5 Hydrostatic Test—Each tube shall be subjected to the hydrostatic test, or, instead ofthis test, a nondestructive electric test may be used when specified by the purchaser.
12. Product Marking
12.1 In addition to the marking prescribed in Specification A450/A450M, the marking shall include the name and order number of the purchaser.
13. Keywords
3.1 cold drawn tube; condenser tubes; heat exchanger tubes; low carbon steel; seamless tube