1.1 This specication describes the production of welded tubes made from various grades of austenitic alloy steel materials in which the (1) external tube surface, (2) internal tube surface, or (3) both internal and external tube surfaces have an enhanced surface for improved heat transfer or fluid flow or both. The strip material used to produce the enhanced surface tubes have been modied to form an enhanced surface strip material from a smooth surface strip material by a cold-forming process or series of processes. The produced welded enhanced tubes maybe used in boilers, superheaters, condensers, evaporators, heat exchangers, and other similar heat transfer apparatus in diameters up to and including 304.8 mm [12 in.] for various wall thicknesses up to and including 8.1 mm [0.320 in.] . 1.2 The tubing sizes and thicknesses usually furnished to this specication are 3.2 mm [1/8 in.] in inside diameter (ID) to 304.8 mm [12 in.] in outside diameter and 0.4 to 8.1 mm [0.015 to 0.320 in.], inclusive, in wall thickness. Tubing having other dimensions may be furnished provided such tubes comply with all other requirements of this specication. 1.3 Mechanical property requirements do not apply to tubing smaller than 3.2 mm [1/8 in.] in ID or for a wall thickness smaller than 0.4 mm [0.015 in.]. 1.4 Optional supplementary requirements are provided and, when one or more of these are desired, each shall be so stated in the order. 1.5 Units-The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.6 The following safety hazards statement pertains to the test method described in Section 17 and the Supplementary Requirements of this specication. A specic warning statement is given in the Supplementary Requirements. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
This development in enhanced surface on welded tubing produces increases in heat transfer efficiency of up to 100 % over conventional tubing depending on fluid velocity and temperature.
Keywordsalloy steel tube; austenitic stainless steel; boiler tubes; condenser tube; duplex stainless steel; enhanced heat transfer tube; feedwater heater tubes; ferritic/austenitic stainless steel; ferritic stainless steel; heat exchanger tube; high-temperature applications; stainless steel tube; steel tube; superheater tube; surface enhancement, temperature service applicationshigh; welded steel tube
The title and scope are in draft form and are under development within this ASTM Committee.Back to Top
Ballot Item Approved as A1098/A1098M-2016 and Pending Publication