ASTM A519 4140

ASTM A 519 – Seamless Carbon and Alloy Steel Mechanical Tubing

This specification covers several grades of carbon and alloy steel seamless mechanical tubing. When welding is used for joining the weldable mechanical tube grades, the welding procedure shall be suitable for the grade, the condition of the components, and the intended service. This specification covers both seamless hot-finished mechanical tubing and seamless cold-finished mechanical tubing in sizes up to and including 12 – 3⁄4 in. (323.8 mm) outside diameter for round tubes with wall thicknesses as required. The tubes shall be furnished in the following shapes, as specified by the purchaser: round, square, rectangular, and special sections.


Grade: 4140

Chemical Compositions (max, %)

Heat AnalysisCMn P SSiCrMo


Mechanical Requirements (min)

These requirements shall not be considered unless specified in the order.

ConditionUltimate Strength   Yield  StrengthElongation in 2
in. or 50 mm,%
Rockwell Hardness B Scale

HR = Hot Rolled,  SR = Stress Relieved,  A = Annealed,  N = Normalized