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 Analysis | C | Mn | P | S | Si | Cr | Mo |
| 0.38-0.43 | 0.75-1.00 | 0.040 | 0.040 | 0.15-0.35 | 0.80-1.10 | 0.15-0.25 |
Mechanical Requirements (min)
These requirements shall not be considered unless specified in the order.
| Condition | Ultimate Strength | Yield Strength | Elongation in 2 in. or 50 mm,% |
Rockwell Hardness B Scale |
| HR | 855 | 621 | 15 | 100 |
| SR | 855 | 689 | 10 | 100 |
| A | 552 | 414 | 25 | 85 |
| N | 855 | 621 | 20 | 100 |
HR = Hot Rolled, SR = Stress Relieved, A = Annealed, N = Normalized