ASTM A519 4140

ASTM A 519 – Seamless Carbon and Alloy Steel Mechanical Tubing

ASTM A519 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

A519 4140 alloy steel is a chromium,molybdenum and manganese containing low alloy steel. It has high fatigue strength, abrasion and impact resistance, toughness,and torsional strength.

Referenced Documents

ASTM Standards:

A 370 Test Methods and Definitions for Mechanical Testing of Steel Products

A 1040 Guide for Specifying Harmonized Standard Grade Compositions for Wrought Carbon,Low-Alloy, and Alloy Steels

E 59 Practice for Sampling Steel and Iron for Determination of Chemical Composition

Military Standards:

MIL-STD-129 Marking for Shipment and Storage

MIL-STD-163 Steel Mill Products Preparation for Shipment and Storage

Federal Standard:

Fed.Std.No.123 Marking for Shipment (Civil Agencies)

Ordering Information

1 Orders for material under this specification should include the following, as required, to describe the desired material adequately:

1.1 Quantity (feet, weight, or number of pieces),

1.2 Name of material (seamless carbon or alloy steel mechanical tubing),

1.3 Form (round,square, rectangular or special shapes),

1.4 Dimensions (round,outside diameters and wall thickness; square and rectangular, outside dimensions and wall thickness; other,specify),

1.5 Length (specific or random, mill lengths),

1.6 Manufacture (hot finished or cold finished),

1.7 Grade,

1.8 Condition (sizing method and thermal treatment),

1.9 Surface finish (special pickling, shot blasting, or ground outside surface, if required),

1.10 Specification designation,

1.11 Individual supplementary requirements, if required,

1.12 End use, if known,

1.13 Packaging,

1.14 Product analysis and chemical analysis, if required,

1.15 Specific requirements, or exceptions to this specification,

1.16 Special marking, and

1.17 Special packing.


Chemical Compositions of ASTM A519 4140 alloy steel pipes (max,%)

4140Heat Analysis


Outside Diameter Tolerances for Round Hot-Finished A519 4140 Tubing

Outside Diameter Size Range,Outside Diameter Tolerance, in. (mm)
in. (mm)OverUnder
Up to 2.999 (76.17)0.020 (0.51)0.020 (0.51)
3.000–4.499 (76.20–114.27)0.025 (0.64)0.025 (0.64)
4.500–5.999 (114.30–152.37)0.031 (0.79)0.031 (0.79)
6.000–7.499 (152.40–190.47)0.037 (0.94)0.037 (0.94)
7.500–8.999 (190.50–228.57)0.045 (1.14)0.045 (1.14)
9.000–10.750 (228.60–273.05)0.050 (1.27)0.050 (1.27)

*Diameter tolerances are not applicable to normalized and tempered or quenched and tempered conditions.


Wall Thickness Tolerances for Round Hot-Finished  A519 4140 Tubing

2.999 in.
(76.19 mm)
3.000 in.(76.2 mm)≤D
≤5.999 in.(152.3mm)
6.000 in.(152.4)≤D
≤10.750 in.(273.05mm)
Under 1512.510.010.0
15 and over10.07.510.0


Wall Thickness Tolerances for Round Cold-Worked A519 4140 Tubing

ID≤1.499 in.
(38.07 mm)
ID≥1.500 in.
(38.1 mm)
25 and Under10.07.5
Over 2512.510.0


Typical Tensile Properties, Hardness and Thermal Condition of A519 4140

Ultimate Strength, ksi[Mpa]120[855]120[855]80[552]120[855]
   Yield  Strength,ksi[Mpa]90[621]100[689]60[414]90[621]
Elongation in  2
in. or 50 mm,%
Rockwell Hardness B Scale10010085100

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