Active Standard ASTM B491 / B491M | Developed by Subcommittee: B07.03
Book of Standards Volume: 02.02
Historical (view previous versions of standard)
This specification covers aluminum and aluminum-alloy extruded round tubes either in coils or straight lengths, for general purpose applications such as refrigeration service, gas lines, oil lines, and instrument lines, in the alloys and tempers. Chemical composition: silicon, iron, copper, manganese, magnesium, chromium, zinc, vanadium, titanium, and aluminum. Tubes produced shall be cooled from an elevated temperature shaping process and naturally aged to a substantially stable condition. The specimen shall then undergo tests to check leakage and any evidence of leak shall be a cause for rejection. The ends of tubes in selected tempers shall be capable of being expanded by forcing a steel pin into the tube without signs of cracks, ruptures, or other defects clearly visible by normal vision. The tubes shall be supplied in the mill finish and shall be uniform as defined by the requirements of this specification and shall be commercially sound. Each tube shall be examined to determine conformance to this specification with respect to general quality and identification marking.
This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.
1.1 This specification covers aluminum and aluminum-alloy extruded round tubes either in coils or straight lengths, for general purpose applications such as refrigeration service, gas lines, oil lines, and instrument lines, in the alloys (Note 0) and tempers shown in , in outside diameters of 0.250 through 0.750 in. [6.00 through 20.00 mm]. For diameters over 0.500 through 0.750 in. [over 12.50 through 20.00 mm], the diameter and wall-thickness tolerances and eddy-current test parameters, if required, shall be agreed upon by the producer and the purchaser. Only tubes in aluminum 1200-H111 and 1235-H111 are sized after extrusion to minimize ovalness.
1.2 Alloy and temper designations are in accordance with ANSI H35.1[H35.1M]. The equivalent Unified Numbering System alloy designations are those of preceded by A9 (for example, A91050 for aluminum 1050) in accordance with Practice E 527. Note 2For extruded tubes see Specification B 221, and for drawn tubes for general-purpose applications see Specification B 483.Note 0
Throughout this specification the term alloy in the general sense includes aluminum as well as aluminum alloy.Note 3
For inch-pound orders specify B 491; for metric orders specify B 491M. Do not mix units.
1.3 For acceptance criteria for inclusion of new aluminum and aluminum alloys in this specification, see .
1.4 The values stated in either inch-pound or SI units are to be regarded separately as standards. The SI units are shown either in brackets or in separate tables. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from two systems will result in nonconformance with the specification.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
B557 Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products
B557M Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products (Metric)
B660 Practices for Packaging/Packing of Aluminum and Magnesium Products
B666/B666M Practice for Identification Marking of Aluminum and Magnesium Products
B881 Terminology Relating to Aluminum- and Magnesium-Alloy Products
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E34 Test Methods for Chemical Analysis of Aluminum and Aluminum-Base Alloys
E55 Practice for Sampling Wrought Nonferrous Metals and Alloys for Determination of Chemical Composition
E215 Practice for Standardizing Equipment for Electromagnetic Testing of Seamless Aluminum-Alloy Tube
E527 Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)
E607 Test Method for Atomic Emission Spectrometric Analysis Aluminum Alloys by the Point to Plane Technique Nitrogen Atmosphere
E716 Practices for Sampling and Sample Preparation of Aluminum and Aluminum Alloys for Determination of Chemical Composition by Spectrochemical Analysis
E1251 Test Method for Analysis of Aluminum and Aluminum Alloys by Spark Atomic Emission Spectrometry
ANSI StandardsH35.2M Dimensional Tolerances for Aluminum Mill Products (Metric)
Federal StandardFed.Std.No.123 Marking for Shipment (Civil Agencies) Available from Standardization Documents Order Desk, DODSSP, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098.
Military StandardMIL-STD-129 Marking for Shipment and Storage
ICS Number Code 23.040.15 (Non-ferrous metal pipes)