ASTM A519 AISI 4130 Alloy Steel Seamless Pipe Manufacturer
We are the manufacturer of high-strength, low-alloy, chromium-molybdenum (Chromoloy) ASTM A519 AISI 4130 seamless pipes — designed for heavy-duty applications requiring toughness, resistance to stress, and high pressure.
What Is ASTM A519 AISI 4130?
ASTM A519 AISI 4130 specifies seamless mechanical tubing made from chromium-molybdenum alloy steel.
This grade — often called Chromoloy or 4130 — offers an outstanding combination of:
✅ High strength
✅ Excellent toughness and resistance to stress
✅ Controlled hardenability and ease of welding
✅ General resistance to atmospheric corrosion
AISI 4130 is widely used in high-performance applications where structural stability under stress is a key requirement.
Material Specification
AISI 4130 alloy steel is a medium carbon, low alloy steel in ASTM A29 standard. ASTM 4140 steel is also commonly referred to as a chromoly steel, or chrome moly steel, containing nominally 0.28-0.33% Carbon, 0.8-1.1% Chromium and 0.15-0.25% Molybdenum.
- Material: AISI 4130 — chromium-molybdenum alloy steel
- Standard: ASTM A519
- Process: Seamless, hot-finished or cold-finished
- Heat treatment: quenched and tempered or normalized, depending on application
- Controlled hardenability and high toughness
ASTM 4130 Steels And Equilvalents Chemical Composition
| Standard | Grade | C | Mn | P | S | Si | Cr | Mo |
| ASTM A29 | 4130 | 0.28-0.33 | 0.40-0.60 | 0.035 | 0.040 | 0.15-0.35 | 0.80-1.10 | 0.15-0.25 |
| EN10250 /EN10083 | 25CrMo4/ 1.7218 | 0.22-0.29 | 0.60-0.90 | 0.025 | 0.035 | ≦0.40 | 0.90-1.2 | 0.15-0.30 |
| JIS G4105 | SCM430/ SCM2 | 0.28-0.33 | 0.60-0.85 | 0.030 | 0.030 | 0.15-0.35 | 0.90-1.2 | 0.15-0.30 |
Chemical Composition of ASTM A519 AISI 4130
| Grade Designation | Carbon | Manganese | Phosphorus, max | Sulfur, max | Silicon | Nickel | Chromium | Molybdenum |
| 4130 | 0.28 – 0.33 | 0.40 – 0.60 | 0.04 | 0.04 | 0.15 – 0.35 | … | 0.80 – 1.10 | 0.15 – 0.25 |
Outside Diameter Tolerances for Round Hot – Finished Tubing
| Outside Diameter Size Range (in. [mm]) | Outside Diameter Tolerance – Over (in. [mm]) | Outside Diameter Tolerance – Under (in. [mm]) |
|---|---|---|
| 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] |
| Notes (A, B, C) | – Diameter tolerances are not applicable to normalized and tempered or quenched and tempered conditions. – The common range of sizes of hot finished tubes is 1 ½ in. [38.1 mm] to 10 ¾ in. [273.0 mm] outside diameter with wall thickness at least 3 % or more of outside diameter, but not less than 0.095 in. [2.41 mm]. – Larger sizes are available; consult manufacturer for sizes and tolerances. |
Wall Thickness Tolerances for Round Hot – Finished Tubing
| Wall Thickness Range as Percent of Outside Diameter | Wall Thickness Tolerance – Percent Over and Under Nominal | ||
|---|---|---|---|
| Outside Diameter 2.999 in. [76.19 mm] and smaller | Outside Diameter 3.000 in. [76.20 mm] to 5.999 in. [152.37 mm] | Outside Diameter 6.000 in. [152.40 mm] to 10.750 in. [273.05 mm] | |
| Under 15 | 12.5 | 10.0 | 10.0 |
| 15 and over | 10.0 | 7.5 | 10.0 |
| Note (A) | – Wall thickness tolerances may not be applicable to walls 0.199 in. [5.05 mm] and less; consult manufacturer for wall tolerances on such tube sizes. |
Size Range and Thickness
We produce ASTM A519 AISI 4130 seamless steel pipe in a wide range of sizes and wall thicknesses, customizable upon request:
Outside Diameter (OD): 1/2” (21.3 mm) to 12” (323.9 mm) or larger
Wall Thickness (WT): SCH 40, SCH 80, SCH 160, XXS, or custom schedules
Lengths: Standard (6 m or 12 m) or custom cut to length
Mechanical Property and hardness for AISI 4130
| Grade Designation | Condition¹ | Ultimate Strength (ksi) | Ultimate Strength (MPa) | Yield Strength (ksi) | Yield Strength (MPa) | Elongation in 2 in. [50 mm], % | Rockwell Hardness B Scale |
|---|---|---|---|---|---|---|---|
| 4130 | HR | 90 | 620 | 70 | 485 | 20 | 89 |
| 4130 | SR | 105 | 725 | 85 | 585 | 10 | 95 |
| 4130 | A | 75 | 515 | 55 | 380 | 30 | 81 |
| 4130 | N | 90 | 620 | 60 | 415 | 20 | 89 |
Applications of AISI 4130
AISI 4130 seamless pipe is broadly used in:
✅ Oil and Gas Pipelines
✅ Automotive Components (Drive Shafts, Roll Cages)
✅ Aerospace Applications (Aircraft Structural Parts)
✅ Power Generation (High-Pressure Tubing)
✅ Structural Applications (Frameworks requiring high strength)
✅ Hydraulics and Fluid Transfer under Pressure
Quality Control and Inspection
Every ASTM A519 AISI 4130 pipe we produce undergoes rigorous quality control and non-destructive testing:
Ultrasonic (UT) Inspection
Hydrostatic Pressure Test
Visual Inspection and Dimensional Check
Material Traceability (with EN 10204 3.1 certificate)
