A500 Grade B

A500 This specification covers cold formed welded and seamless carbon steel round, square, rectangular, or special shape structural tubing for welded, riveted, or bolted construction of bridges and buildings, and for general structural purposes.

Typical Chemical Properties
Grades A, B, and D – Heat analysis Grades A, B, and D – Product analysis Grade C – Heat analysis Grade C – Product analysis
Carbon, maximum % 0.26 0.30 0.23 0.27
Manganese, maximum % 1.35 1.40 1.35 1.40
Phosphorous, maximum, % 0.035 0.045 0.035 0.045
Sulfur, maximum, % 0.035 0.045 0.035 0.045
Copper, minimum (if Copper-containing steel is specified in the purchase order) % 0.20 0.18 0.20 0.18
Typical Mechanical Properties
Round Structural Tubing Grade A Grade B Grade C Grade D
Tensile Strength, Minimum, psi [Mpa] 45,000 [310] 58,000 [400] 62,000 [425] 58,000 [400]
Yield Strength, Minimum, psi [Mpa] 33,000 [230] 42,000 [290] 46,000 [315] 36,000 [250]
Shaped Structural Tubing Grade A Grade B Grade C Grade D
Tensile Strength, Minimum, psi [Mpa] 45,000 [310] 58,000 [400] 62,000 [425] 58,000 [400]
Yield Strength, Minimum, psi [Mpa] 39,000 [270] 46,000 [315] 50,000 [345] 36,000 [250]
Typical Permissible Variations in Wall Thickness
The minimum wall thickness at any point of measurement on the tubing shall be not more than 10% less than the specified wall thickness. The maximum wall thickness, excluding the weld seam of welded tubing, shall be not more than 10% greater than the specified wall thickness. For square and rectangular tubing, the wall thickness requirements shall apply only to the centers of the flats
Typical Permissible Variations in Outside Diameter
Round Structural Tubing – The outside diameter shall not vary more than +/-0.5%, rounded to the nearest 0.005 inch [0.1 mm], from the specified outside diameter for specified outside diameters 1.900 in. [48 mm] and smaller, and +/-0.75%, rounded to the nearest 0.005 in. [0.1 mm], from the specified diameter for specified diameters 2.00 in. [5 cm] and larger. The outside diameter measurements shall be made at positions at least 2 in. [5 cm] from the ends of the tubing.
Square and Rectangular Structural Tubing – The Outside dimensions, measured across the flats at positions at least 2 in. [5 cm] from the ends of the tubing, shall not vary from the specified outside dimensions by more than the applicable amount shown below, which includes an allowance for convexity of concavity.
Typical Permissible Variations in Outside Diameter
Specified Outside Large Flat Dimension, in. [mm] Permissible Variations Over and Under Specified Outside Flat Dimensions,* in. [mm]
2.500 [65] or under 0.020 [0.5]
Over 2.500 to 3.500 [65 to 90], incl. 0.025 [0.6]
Over 3.500 to 5.500 [90 to 140], incl. 0.030 [0.8]
Over 5.500 [140] 0.01 times large flat dimension

*The permissible variations include allowances for convexity and concavity. For rectangular tubing having a ratio of outside large to small dimension less than 1.5, and for square tubing, the permissible variations in small flat dimension shall be identical to the permissible variations in large flat dimensions. For rectangular tubing having a ratio of outside large to small flat dimension in the range of 1.5 to 3.0 inclusive, the permissible variations in small flat dimension shall be 1.5 times the permissible variations in large flat dimension. For rectangular tubing having a ratio of outside large to small flat dimension greater than 3.0, the permissible variations in small flat dimension shall be 2.0 times the permissible variations in large flat dimension.

Straightness – The permissible variation for straightness of structural tubing shall be 1/8 in. times the number of feet [10 mm times the number of meters] of total length divided by 5.

Squareness of sides – For square and rectangular structural tubing, adjacent side shall be square (90 degrees), with a permissible variation of +/-2 degrees maximum.

Radius of Corners – For square and rectangular structural tubing, the radius of each outside corner of the section shall not exceed three times the specified wall thickness.

Information provided is “Typical” for specific requirements please inquire.