GB/T 3094 is the Chinese national standard that regulates cold drawn shaped steel tubes, including square, rectangular, oval, and custom cross-section pipes. It defines dimensional tolerances, surface finish, and mechanical requirements for structural or mechanical use.
This article explains the scope of GB/T 3094, its dimensional standards, applicable materials, and how YIGE Steel supports full compliance with high-precision mold development.
Standard Overview (Scope, History, Use)
GB/T 3094 is officially titled “Cold drawn shaped steel tubes”, and it covers:
- Square, rectangular, elliptical, and other non-circular cross sections
- Seamless or welded tubes produced by cold drawing
- Pipes used in structural, mechanical, automotive, and equipment frames
Latest version: GB/T 3094-2012
Replaces: GB/T 3094-1986 (older standard)
Regulating body: Standardization Administration of China (SAC)
This standard ensures dimensional stability, shape accuracy, and consistent appearance for cold-formed special tubes.
Dimensional and Tolerance Specifications
| Parameter | Specification (Typical) |
|---|---|
| Cross-section types | Square, Rectangular, Elliptical, Special |
| OD (side A/B) | 10 mm – 600 mm |
| Wall Thickness (WT) | 0.5 mm – 30 mm |
| Length | 4 m – 12 m, customized available |
| Tolerance – Side length | ±0.2–0.8% depending on size |
| Tolerance – WT | ±10% (or customized) |
| Straightness | ≤1.5 mm/m |
| Corner Radius (R) | Sharp corners allowed, R ≤ 0.5S |
It is widely used in bending, laser cutting, and welding applications that require high profile consistency and precision.
Material Grades and Delivery Conditions
GB/T 3094 does not specify fixed steel grades — it refers to corresponding base material standards such as:
- GB/T 8162 (General seamless pipe)
- GB/T 1591 (Low alloy structural steels like Q355)
- GB/T 699 (Carbon structural steel like 20#, 45#)
- GB/T 3077 (Alloy structural steels)
Commonly used grades include:
- Q195 / Q235 / Q355
- 20# / 45# / 40Cr
- 35CrMo / 42CrMo
- Stainless grades on demand: 304, 316L
Delivery condition:
Cold drawn + annealed / normalized / tempered based on application.
Application Scenarios
GB/T 3094 tubes are ideal for:
- Agricultural machinery frames
- Construction machine arms
- Automotive structural parts
- Cranes and aerial platforms
- Laser-cut special brackets
- Mechanical equipment frames
Especially suitable for non-standard, small-batch, high-precision needs where traditional round pipes cannot meet structural or aesthetic requirements.
How It Compares to EN & ASTM Standards
| Standard | Region | Focus | Notes |
|---|---|---|---|
| GB/T 3094 | China | Cold drawn shaped tubes | Includes sharp corner control, mold-driven |
| EN 10305-5 | EU | Welded/DOM precision profiles | More automotive-focused, welded preferred |
| ASTM A500 | US | Structural tubes | Square/rectangular, but welded-based |
GB/T 3094 is more flexible for customized cross-sections, supporting very small R-corners, deep profiles, and varying wall thicknesses — often used in high-end Chinese OEM equipment.
YIGE Steel’s Capability & Compliance
YIGE Steel is a leading manufacturer of GB/T 3094-compliant products with in-house mold and cold-drawing capabilities.
Our strengths:
- ✅ Size Range: 10×10 mm – 600×600 mm, WT 1–30 mm
- ✅ Corner Control: Sharp corners, R ≤ 0.5S, or round corners
- ✅ Material: Q355, 20#, 45#, alloy steels, stainless steel
- ✅ MOQ: 1 ton (seamless), 25 tons (welded)
- ✅ Delivery: Mold-making within 7 days, sample in 3–5 days
- ✅ Applications: Structure, machinery, export-ready
- ✅ Certifications: ISO9001, CE, BV, IATF16949 (welded)
We offer one-stop engineering support — from CAD assistance to mold development to precision quality inspection.
Conclusion
GB/T 3094 is the go-to standard in China for cold drawn non-round steel tubes, offering tight tolerance control and customized geometry. Whether you need square, rectangular, or complex profiles, this standard ensures mechanical reliability and aesthetic consistency.
YIGE Steel delivers high-strength, precision-shaped tubes with full control over molds, materials, and finishing. Contact us for special-shaped seamless or welded pipe solutions tailored to your design.
