ASTM A254 – Standard Specification for Copper-Brazed Steel Tubing
This specification covers double-wall, copper brazed steel tubing suitable for general engineering uses, particularly in the automotive, refrigeration, and stove industries for fuel lines, brake lines, oil lines, heating and cooling units, and the like. The tubing shall be made by rolling steel strip into the form of tubing and subsequently copper brazing in a reducing atmosphere. The steel shall conform to the prescribed chemical composition and shall be subjected to heat analysis and product analysis. Tension, flattening, expansion, bending, and pressure proof tests shall be made in accordance with the specification.
1.1 This specification covers double-wall, copper-brazed steel tubing suitable for general engineering uses, particularly in the automotive, refrigeration, and stove industries for fuel lines, brake lines, oil lines, heating and cooling units, and the like. The tubing is available in either of two types, single strip or double strip.
1.2 Units—This specification is expressed in both inch-pounds units and in SI units; however, unless the purchase order or contract specifies the applicable M specification designation (SI units), the inch-pound units shall apply. 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 may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. In this specification hard or rationalized conversions apply to diameters, lengths, and tensile properties. Soft conversion applies to other SI measurements.