GB/T 8162 42CrMo Seamless Steel Pipe Material
GB/T 8162 42CrMo Seamless Steel Pipe: High-Strength Alloy for Structural Applications
Comprehensive material properties of 42CrMo seamless steel pipe per GB/T 8162, including chemistry, mechanics, physics, and international equivalents for structural engineering.
Hot rolling, cold drawing, heat treatment (quenching & tempering, normalizing, annealing)
- Phone : +8618037372205
- Email : [email protected]
- WhatsApp: Contact via Whtsapp
- WeChat: +8618037372205
GB/T 8162 42CrMo Seamless Steel Pipe Introduction
42CrMo is a medium carbon quenched and tempered alloy steel commonly used in structural seamless pipes under GB/T 8162. It exhibits excellent hardenability, high strength, and good toughness after heat treatment. Typical applications include heavy-duty machinery components, drill pipes, shafts, and pressure-resistant structures. The steel is characterized by its chromium-molybdenum composition, providing optimal balance between tensile strength (≥1080 MPa) and yield strength (≥930 MPa) when heat-treated. Delivery is mainly in quenched and tempered condition, ensuring uniform mechanical properties and improved wear resistance. This grade is widely adopted in the oil & gas, automotive, and power generation industries due to its reliable performance under dynamic loads and elevated temperatures.
- Standard: GB/T 8162-2018
- Classification: Alloy structural steel
- Shape: Seamless hollow sections
GB/T 8162 42CrMo Seamless Steel Pipe Chemical Composition
The chemical composition of 42CrMo seamless pipe in accordance with GB/T 8162 (also referenced in GB/T 3077 for alloy structural steel). Limits ensure consistent hardenability and mechanical properties. Cr and Mo additions improve toughness and heat resistance.
| Element | Content (%) | Remarks |
|---|---|---|
| Carbon (C) | 0.38 – 0.45 | Key for strength and hardness |
| Silicon (Si) | 0.17 – 0.37 | Deoxidizer |
| Manganese (Mn) | 0.50 – 0.80 | Hardenability enhancer |
| Phosphorus (P) | ≤ 0.035 | Max impurity |
| Sulfur (S) | ≤ 0.035 | Max impurity |
| Chromium (Cr) | 0.90 – 1.20 | Carbide former, improves hardenability |
| Molybdenum (Mo) | 0.15 – 0.25 | Grain refiner, creep resistance |
| Nickel (Ni) | ≤ 0.30 | Residual |
| Copper (Cu) | ≤ 0.30 | Residual |
GB/T 8162 42CrMo Seamless Steel Pipe Physical Properties
Typical physical data for 42CrMo steel at room temperature unless noted. These values are for general guidance and may slightly vary with heat treatment and composition. Sources: standard technical handbooks, not design guarantees.
| Property | Typical Value | Unit | Test Condition / Remarks |
|---|---|---|---|
| Density (ρ) | 7.85 | g/cm³ | At 20°C |
| Modulus of elasticity (E) | 210 | GPa | At 20°C |
| Shear modulus (G) | 81 | GPa | Calculated from E and ν |
| Poisson's ratio (ν) | 0.3 | - | Elastic range |
| Thermal expansion coefficient (α) | 12.1 | 10⁻⁶/K | 20 – 100°C |
| Thermal expansion coefficient (α) | 12.7 | 10⁻⁶/K | 20 – 200°C |
| Thermal expansion coefficient (α) | 13.2 | 10⁻⁶/K | 20 – 300°C |
| Thermal conductivity (λ) | 44.0 | W/(m·K) | At 100°C |
| Thermal conductivity (λ) | 42.0 | W/(m·K) | At 200°C |
| Specific heat capacity (c) | 460 | J/(kg·K) | At 20°C |
| Electrical resistivity (ρ_e) | 0.23 | Ω·mm²/m | At 20°C |
GB/T 8162 42CrMo Seamless Steel Pipe Mechanical Properties
Values extracted from GB/T 8162-2018 for heat-treated 42CrMo seamless pipes. Testing performed on machined specimens after standard heat treatment (quenching 850°C oil, tempering 560°C water/oil). Minimum requirements are guaranteed.
- For pipe wall thickness variations, properties may be agreed upon.
| Property | Minimum Value | Unit | Test Condition / Remarks |
|---|---|---|---|
| Tensile strength (Rm) | 1080 | MPa | At room temperature |
| Yield strength (ReH or Rp0.2) | 930 | MPa | Lower yield / 0.2% offset |
| Elongation after fracture (A) | 12 | % | Gauge length 5.65√S₀ |
| Reduction of area (Z) | 45 | % | |
| Impact energy (KV₂) | 63 | J | Charpy U-notch, room temperature |
| Brinell hardness (HBW) | ≤ 217 | - | In annealed or high-tempered condition |
GB/T 8162 42CrMo Seamless Steel Pipe Exact Equivalent Material Standards and Substitution Grades
| Country/Region | Standard | Grade | Remarks |
|---|---|---|---|
| Germany | DIN EN 10083-3 | 42CrMo4 (1.7225) | Identical composition and heat treatment |
| Japan | JIS G4105 | SCM440 | Slight Mn range difference, otherwise equivalent |
| USA | ASTM A519 | 4140 | Seamless mechanical tubing, heat-treatable |
| UK | BS 970-1 | 708M40 | Quenched & tempered condition |
| France | NF A35-552 | 42CD4 | Old designation, equivalent to 42CrMo4 |
| International | ISO 683-1 | 42CrMo4 | Harmonized standard |
GB/T 8162 42CrMo Seamless Steel Pipe Application Introduction
42CrMo tubular products serve demanding sectors requiring high static and dynamic loads. Its excellent combination of strength, ductility, and wear resistance makes it a preferred material for moving parts and pressurized components. Typical usage spans:
- Mechanical engineering: heavy-duty shafts, gears, crankshafts, connecting rods
- Oil & gas: drill collars, tool joints, pup joints
- Automotive: transmission shafts, steering components
- Power generation: turbine shafts, boiler supports
Product Applications: Structural seamless pipes, Hollow bars for precision engineering, Machined hollow sections, Lightweight drive shafts, High-pressure cylinders
Processed into products: Drill pipe connectors (tool joints), Axle tubes and spindles, Crankshafts and camshafts, Rolling mill spindles, Fasteners and pins, Couplings and hubs
Application industries: Oil & Gas, Automotive, Heavy Machinery, Power Generation, Mining & Construction, Chemical Processing
GB/T 8162 42CrMo Seamless Steel Pipe Similar/Alternative Materials for Reference
| Country/Region | Standard | Grade | Remarks |
|---|---|---|---|
| China | GB/T 3077 | 40Cr | Lower Mo, slightly lower hardenability |
| USA | ASTM A29 | 4042 | Higher Mo, suitable for cyanide hardening |
| Germany | DIN EN 10083-3 | 41Cr4 | Without Mo, lower toughness at high strengths |
| Japan | JIS G4105 | SCM435 | Lower carbon, lower tensile strength |
| Russia | GOST 4543 | 38ХМ (38KhM) | Slightly lower carbon and Cr content |
Notes:
Heat treatment is critical: 42CrMo seamless pipes must be quenched and tempered to achieve specified properties. Decarburization and surface condition shall meet GB/T 8162 requirements. Non-destructive testing (ultrasonic or eddy current) often applied for safety-critical applications. Supplementary requirements (e.g., Charpy impact at low temperature) can be agreed upon between supplier and purchaser. Contact technical support for welding and forming guidelines.
- Share
