
Q355B Seamless Cold Drawn Steel Tube Low Alloy Steel Pipe For Precision Applications
Material
Q355B seamless cold drawn steel tubes are a type of low alloy steel pipe known for their high strength and excellent mechanical properties. These tubes are designed for precision applications where dimensional accuracy and surface finish are critical. The Q355B grade is part of the Chinese GB/T standard, which specifies the technical requirements for seamless steel tubes.
Specification
Q355B seamless steel tubes are manufactured using a cold drawing process, which enhances their dimensional accuracy and surface quality. These tubes are available in various sizes and thicknesses to meet specific application requirements. The specification of Q355B tubes typically includes:
- Standard: GB/T 8162, GB/T 8163
- Outer Diameter: 10mm to 530mm
- Wall Thickness: 1mm to 30mm
- Length: As required (usually up to 12 meters)
- Surface Treatment: Black, galvanized, or as specified
Key Features
- High Strength: Q355B steel offers excellent tensile strength and yield strength, making it suitable for demanding applications.
- Good Weldability: The low carbon content ensures good weldability, allowing for easy fabrication and assembly.
- Corrosion Resistance: The alloying elements provide enhanced resistance to corrosion and oxidation.
- Precision: The cold drawing process ensures tight dimensional tolerances and a smooth surface finish.
Chemical Composition
The chemical composition of Q355B steel is crucial for its mechanical properties and performance. The table below outlines the typical chemical composition:
Element | Composition (%) |
Carbon (C) | ≤ 0.20 |
Silicon (Si) | ≤ 0.50 |
Manganese (Mn) | 1.00 - 1.60 |
Phosphorus (P) | ≤ 0.030 |
Sulfur (S) | ≤ 0.030 |
Vanadium (V) | ≤ 0.10 |
Niobium (Nb) | ≤ 0.07 |
Titanium (Ti) | ≤ 0.20 |
Mechanical Properties
The mechanical properties of Q355B steel tubes are essential for their performance in precision applications. The table below presents the typical mechanical properties:
Property | Value |
Tensile Strength (MPa) | 470 - 630 |
Yield Strength (MPa) | ≥ 355 |
Elongation (%) | ≥ 20 |
Impact Energy (J) | ≥ 34 (at -20°C) |
Similar Standards and Steel Grades
Q355B steel is comparable to several international standards and steel grades, including:
- ASTM A572 Grade 50
- EN 10025 S355JR
- JIS G3106 SM490
These standards and grades share similar mechanical properties and chemical compositions, making them suitable alternatives for specific applications.
Application
Q355B seamless cold drawn steel tubes are widely used in various industries due to their excellent mechanical properties and precision. Common applications include:
- Automotive Industry: Used in the manufacturing of precision components such as drive shafts and suspension systems.
- Construction: Employed in structural applications where high strength and durability are required.
- Machinery Manufacturing: Utilized in the production of hydraulic cylinders, machine parts, and other precision components.
- Oil and Gas Industry: Suitable for use in pipelines and other equipment exposed to harsh environments.





TORICH Group, an one-stop service provider of raw materials engaged in raw material production, R&D and
trade, has 30+ years of experience in the market, exported to 56 +countries, and won good reputation and
credibility among domestic and foreign customers.
The company's production plant covers an area of over 10,000 square meters, with an annual production
capacity of 50,000 tons of materials and a comprehensive trading and warehousing capacity of 100,000 tons, which can satisfy customers' personalized needs for raw materials in terms of diversity and timeliness.
The group holds shares in more than ten domestic production entities, whose main products include
seamless steel pipes ( carbon steel and stainless steel), welded pipes ( carbon steel and stainless steel), pipe fittings ( carbon steel and stainless steel), titanium (titanium tubes, titanium rods, titanium cakes, titanium plates, etc.), aluminum (aluminum tubes, aluminum rods, aluminum die casting, aluminum casting, CNC machining), and CNC deep processing of metal materials such as tubes, rods, and casting parts.
Over the past 30 years, the company has been gradually developing new technologies and materials to meet
the growing needs of customers and various diversified needs, exporting to more than 56 countries and still
increasing the number of exporting countries, aiming to help customers to solve the demand for raw materials, and to facilitate one-stop purchasing for customers.






Q: Are you trading company or manufacturer ?
A: manufacturer,also can do trading.
Q: How long is your delivery time?
A: Generally speaking,it is 10-15 days if the goods are in stock,or it is 30-40 days if the goods are not in stock, it is according to quantity.
Q: Do you provide samples? is it free or extra ?
A: Yes, we could offer the sample for free charge but need pay the cost of freight.
Q: What is your terms of payment ?
A: Payment<=2000USD, 100% in advance. Payment>=2000USD, 30% T/T in advance ,balance before shippment.
If you have another question, pls feel free to contact with me.