Product Parameters of 40Mn2 Steel Pipe
| Category | Specifications |
|---|---|
| Chemical Composition | Carbon (C): 0.35-0.45% Manganese (Mn): 1.60-1.80% Silicon (Si): 0.17-0.37% Sulfur (S): ≤0.035% Phosphorus (P): ≤0.035% Chromium (Cr): ≤0.20% Nickel (Ni): ≤0.30% Copper (Cu): ≤0.25% |
| Mechanical Properties | Tensile Strength (σb): ≥885 MPa Yield Strength (σs): ≥735 MPa Elongation (δ5): ≥12% Reduction of Area (ψ): ≥45% Hardness (HB): ≤217 (untreated) |
| Heat Treatment | Quenching in oil (critical diameter: 8.5-23mm) or water (20-42mm), tempered at 540°C |
| Delivery State | Supplied in normalized, annealed, or tempered condition |
| Dimensions | Outer Diameter: 10-630 mm Wall Thickness: 1.5-40 mm Length: Customizable |
| Standards | GB/T 3077-1999 (China), ASTM A29/A29M-04 (USA) |
Applications of 40Mn2 Steel Pipe
40Mn2 steel pipe is widely used in high-stress mechanical and structural applications due to its high strength, wear resistance, and moderate toughness:
Heavy Machinery & Automotive
Gears, shafts, and connecting rods (e.g., crankshafts, camshafts) requiring high fatigue resistance
Automotive components like piston rods and transmission parts
Power & Energy Industry
High-pressure pipelines (e.g., oil drilling, steam boilers) withstanding temperatures up to 450°C
Geological drill pipes (e.g., DZ50 grade) for deep-well exploration
Construction & Structural Engineering
Railway axles and bridge components under dynamic loads
Heavy-duty bolts and fasteners for industrial equipment
Specialized Uses
Cold-drawn precision tubes for hydraulic cylinders (tolerance ±0.05mm)
Wear-resistant parts (e.g., rollers, sprockets) after surface hardening
Key Advantages
High Strength-to-Weight Ratio: Comparable to 40Cr steel but at lower cost
Weldability: Requires preheating (150-200°C) and low-hydrogen welding rods
Machinability: Moderate difficulty; recommended for CNC machining with carbide tools
