ASTM A500

 

Standard Specification for Cold-formed Welded and Seamless Carbon Steel Structural Tubing in Round and Shapes

 

Scope

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 building and for general purposes.

Chemical Composition

Element
Composition %
Grades A, B, and D
Grade C
Heat Analysis
Product Analysis
Heat Analysis
Product Analysis
Carbon, maxA 0.26 0.30 0.23 0.27
Manganese, max A 1.35 1.40 1.35 1.40
Phosphorus, max 0.035 0.045 0.035 0.045
Sulphur, maxB 0.035 0.045 0.035 0.045
Copper, min 0.20 0.18 0.20 0.18

A For each reduction of 0.01 percentage point below the specified maximum for carbon, an increase of 0.06 percentage point above the specified maximum for manganese is permitted, up to a maximum of 1.50% by product analysis.
B If copper-containing steel is specified in the purchase order.

Tensile Requirement

Round Structural Tubing
 
Grade A
Grade B
Grade C
Grade D
Tensile strength, min, psi (MPa)
45 000 (310)
58 000 (400)
62 000 (425)
58 000 (400)
Yield strength, min, psi (MPa)
33 000 (230)
42 000 (290)
46 000 (315)
36 000 (250)
Elongation in 2 in. (50 mm), min, %D
25A
23B
21C
23B
Shaped Structural Tubing
 
Grade A
Grade B
Grade C
Grade D
Tensile strength, min, psi (MPa)
45 000 (310)
58 000 (400)
62 000 (425)
58 000 (400)
Yield strength, min, psi (MPa)
39 000 (270)
46 000 (315)
50 000 (345)
36 000 (250)
Elongation in 2 in. (50 mm), min, %D
25A
23B
21C
23B

 

A Applies to specified wall thickness (t) equal to or greater than 0.120 in (3.05 mm). For lighter specified wall thicknesses, the minimum elongation values shall be calculated by the formula: percent elongation in 2 in. [50 mm] = 56t + 17.5, rounded to the nearest percent. For A500M use the following formula: 2.2t + 17.5, rounded to the nearest percent.
B Applies to specified wall thickness (t) equal to or greater than 0.180 in (4.57 mm). For lighter specified wall thicknesses, the minimum elongation values shall be calculated by the formula: percent elongation in 2 in. [50 mm] = 61t + 12, rounded to the nearest percent. For A500M use the following formula: 2.4t + 12, rounded to the nearest percent.
C Applies to specified wall thickness (t) equal to or greater than 0.120 in (3.05 mm). For lighter specified wall thicknesses, the minimum elongation values shall be by agreement with the manufacturer.
D The minimum elongation values specified apply only to tests performed prior to shipment of the tubing.