Q460D SHS/RHS Pipe per GB/T 3094
Q460D Steel SHS/RHS Pipe per GB/T 3094: High-Strength Cold-Drawn Hollow Section
Detailed properties and applications of Q460D cold-drawn square and rectangular hollow sections according to GB/T 3094, including chemical, mechanical, and physical data.
Cold-drawing, welding with subsequent cold-drawing (if welded tube used as mother pipe), bending, machining
- Phone : +8618037372205
- Email : [email protected]
- WhatsApp: Contact via Whtsapp
- WeChat: +8618037372205
Q460D SHS/RHS Pipe per GB/T 3094 Introduction
Q460D is a low-alloy high-strength structural steel grade specified in GB/T 1591, and when manufactured into cold-drawn square (SHS) and rectangular (RHS) hollow sections, it is governed by GB/T 3094. This material offers a minimum yield strength of 460 MPa, excellent low-temperature toughness (impact energy ≥34J at -20°C), and good weldability. The cold-drawing process enhances dimensional accuracy and surface finish. Typical applications include heavy-duty structures, bridges, machinery, and offshore engineering where high strength and weight reduction are required. The D quality suffix indicates fine-grain practice and guaranteed impact properties at -20°C.
Q460D SHS/RHS Pipe per GB/T 3094 Chemical Composition
Chemical composition shall comply with GB/T 1591-2018 for Q460D. Maximum contents unless a range is shown. For tube products, slight deviations allowed per product standard, but these values are the guideline from the base material standard. Elements like Nb, V, Ti may be added singly or in combination to achieve grain refinement and precipitation hardening.
| Element | Value (max or range) | Remarks |
|---|---|---|
| C | ≤0.18 | |
| Si | ≤0.60 | |
| Mn | ≤1.80 | 1.00~1.80 typical |
| P | ≤0.030 | |
| S | ≤0.025 | |
| Cr | ≤0.30 | |
| Ni | ≤0.80 | |
| Cu | ≤0.55 | |
| Mo | ≤0.20 | |
| Al (total) | ≥0.020 | minimum for fine-grain practice |
| Nb | 0.005~0.05 | or as agreed |
| V | 0.01~0.12 | or as agreed |
| Ti | 0.01~0.12 | or as agreed |
| Nb+V+Ti | ≤0.22 | If combined |
| Ceq (CEV) | ≤0.47 | carbon equivalent for weldability |
Q460D SHS/RHS Pipe per GB/T 3094 Thermal and Electrical Physical Properties
The following physical properties are typical for Q460D type low-alloy steel at room temperature unless noted. They are not part of the delivery specification but are useful for design. Values are average and may vary with processing conditions.
- Density: 7.85 g/cm³.
- Elastic modulus: 200 GPa.
- Shear modulus: 77 GPa.
- Poisson's ratio: 0.30.
- Thermal expansion (20-100°C): 12.0×10⁻⁶ /K.
- Thermal conductivity: 45 W/(m·K).
- Specific heat capacity: 460 J/(kg·K).
- Electrical resistivity: 2.2×10⁻⁷ Ω·m (0.22 μΩ·m).
| Property | Typical Value | Unit | Test Condition / Temperature |
|---|---|---|---|
| Density (ρ) | 7.85 | g/cm³ | ambient |
| Modulus of Elasticity (E) | 200 | GPa | ambient |
| Shear Modulus (G) | 77 | GPa | ambient |
| Poisson's Ratio (ν) | 0.30 | — | ambient |
| Thermal Expansion Coefficient (α) | 12.0 | 10⁻⁶ /K | 20-100°C |
| Thermal Conductivity (λ) | 45 | W/(m·K) | ambient |
| Specific Heat Capacity (cp) | 460 | J/(kg·K) | ambient |
| Electrical Resistivity (ρe) | 2.2×10⁻⁷ | Ω·m | ambient |
Q460D SHS/RHS Pipe per GB/T 3094 Mechanical Properties
Mechanical properties for Q460D SHS/RHS as per GB/T 3094-2012. The values apply to wall thicknesses ≤16 mm. For greater thicknesses, tensile requirements may be agreed. All tests at room temperature except impact. Impact test at -20°C is mandatory for D-quality. Samples taken from the tube body.
- Yield strength (ReH) for wall thickness ≤16 mm: ≥460 MPa.
- Tensile strength (Rm): 550-720 MPa.
- Elongation after fracture (A) using gauge length 5.65√S0: ≥17%.
- Impact energy (KV2) at -20°C: ≥34 J (average of 3 tests, individual min 27 J).
| Property | Required Value | Unit | Test Condition |
|---|---|---|---|
| Yield Strength (ReH) | ≥460 | MPa | t ≤16 mm, ambient |
| Tensile Strength (Rm) | 550~720 | MPa | ambient |
| Elongation (A) | ≥17 | % | L0=5.65√S0 |
| Impact Energy (KV2) | ≥34 (avg) | J | -20°C, longitudinal, 10×10×55 mm specimen |
| Impact Energy (KV2) individual | ≥27 | J | -20°C, longitudinal |
| Bend Test (if required) 180° | d=3a | bend diameter | t ≤16 mm, a=wall thickness |
Q460D SHS/RHS Pipe per GB/T 3094 Completely Equivalent Material Standards and Substitute Grades
| Country / Region | Standard | Grade | Remarks |
|---|---|---|---|
| China | GB/T 1591-2018 | Q460D | Base standard for chemistry and mechanical properties; Q460D plates/bars/welded tubes |
| China | GB/T 8162-2018 | Q460D | Seamless steel tubes for structural purposes; similar grade but different tube manufacturing process |
| — | — | — | No direct complete equivalence exists because Q460D is a Chinese grade. Closest matches are provided in the similar materials section. |
Q460D SHS/RHS Pipe per GB/T 3094 Application Introduction
Q460D cold-drawn SHS/RHS tubes are ideal for weight-critical, high-strength structural applications. Their high yield strength allows for thinner walls compared to mild steel, leading to material savings. The cold-drawn finish provides tight dimensional tolerances and an improved surface. They are readily weldable with low-hydrogen processes and suitable for moderate cold forming. Typical industries and components include:
Product Applications: Square (SHS) and rectangular (RHS) hollow structural sections, typically from 20×20 mm up to 500×500 mm or larger, depending on the manufacturer's capability., Special-shaped cold-drawn tubes (hexagonal, octagonal, oval) to order., Fabricated structural assemblies (trusses, columns, beams).
Processed into products: Heavy-duty columns and beams in steel framed buildings, Truss chords and web members for large-span roofs, Crane booms and lattice structures, Offshore platform braces and legs, Axle housings and chassis frames for heavy vehicles, Hydraulic cylinder tubes (if honed after drawing), Agricultural implement frames subjected to high stress, Architectural exposed structures where appearance and strength are required
Application industries: Construction and infrastructure (high-rise buildings, stadiums, bridges), Transportation (truck chassis, trailer frames, railway wagons), Offshore and shipbuilding (platform structures, crane pedestals), Machinery and equipment (heavy machine frames, hydraulic cylinder bodies), Energy (transmission towers, wind turbine towers, solar support structures), Mining and agricultural equipment (boom arms, chassis)
Q460D SHS/RHS Pipe per GB/T 3094 Similar or Near-Equivalent Material Recommendations
| Country / Region | Standard | Grade | Remarks |
|---|---|---|---|
| Europe | EN 10025-3 | S460N / S460NL | Thermomechanical rolled fine-grain structural steel. Yield 460 MPa, impact at -20°C (N) or -50°C (NL). Composition similar, but CEV may differ. NL is more comparable to Q460D. |
| United States | ASTM A572/A572M | Grade 65 | Yield 450 MPa (65 ksi) min, tensile 550 MPa. Not exactly 460 MPa but close. No guaranteed low-temperature impact unless supplementary requirement. |
| United States | ASTM A500/A500M | Grade C | Cold-formed welded and seamless carbon steel structural tubing. Yield 345 MPa, tensile 425 MPa. Strength lower; only approximate shape equivalent. |
| Japan | JIS G 3106 | SM570 | Yield ≥460 MPa for t≤16, tensile 570-720 MPa. Impact at 0°C or -5°C if special quality. Not exactly D-grade (-20°C) but similar strength. |
| International | ISO 630-3 | Fe 460D | Yield 460 MPa, impact -20°C. Chemical composition similar but not identical. This is the closest international equivalent from ISO. |
Notes:
- For SHS/RHS with wall thickness >16 mm, mechanical properties may be agreed between purchaser and manufacturer; some strength reduction is possible.
- If the tube is produced from welded mother pipe and then cold-drawn, the weld seam quality shall conform to GB/T 3094 and base material standard.
- Additional non-destructive testing (e.g., ultrasonic, eddy current) can be specified.
- Surface condition: Cold-drawn tubes have a smooth, bright surface free from scale. Slight internal lubricant residues may be present.
- All data are for reference and should be confirmed by the actual mill certificate. The information complies with publicly available standards as of the revision date.
- Share
