Cold Drawn Seamless Tubing Cold Finished Seamless Steel Tube For Mechanical Engineering

Summary:
BS6323-4 cold drawn seamless tubing is a precision-engineered carbon steel tube designed for demanding mechanical and general engineering applications. Manufactured via a seamless drawing process and cold finished to tight dimensional tolerances, these tubes provide excellent strength-to-weight ratios, superior surface finish, and consistent mechanical properties. They comply with BS 6323-4 delivery conditions (BK, BKW, GBK, NBK, GZP, NZP) and are often specified alongside comparable grades from ASTM, EN, JIS, GB, and GOST standards.

1. Material

BS6323-4 tubes are fabricated from low-carbon hot-rolled strip steel and cold drawn to achieve a refined grain structure, resulting in enhanced mechanical properties and surface finish. The typical base material is mild carbon steel, suitable for subsequent machining, welding, or forming operations.

2. Specifications

• Outside Diameter (O.D.): 6 mm to 280 mm

• Wall Thickness (W.T.): 1 mm to 30 mm

• Lengths: Random lengths of 4 m–7 m or cut-to-length per customer requirements

• Delivery Conditions:

  • BK (Cold finished/hard)

  • BKW (Cold finished/soft)

  • GBK (Annealed)

  • NBK (Normalized)

  • GZP, NZP (Bright annealed, normalized & de-scaled)

3. Chemical Composition

4. Mechanical Properties

5. Main Features

• Precision Finish: Tight tolerances on diameter (±1 %) and wall thickness (±10 %) ensure minimal post-machining

• Enhanced Strength: Cold drawing refines microstructure, boosting tensile and yield strengths over hot-finished equivalents

• Surface Quality: Smooth, scale-free surface reduces friction and wear in dynamic applications

• Consistent Performance: Uniform properties along tube length support high-precision assemblies

6. Standards

• British Standard: BS 6323-4:1982 (Cold finished seamless steel tubes)

• European: EN 10305-1 (Cold drawn tubes for hydraulic and pneumatic applications)

• American: ASTM A519 (Seamless carbon and alloy steel mechanical tubing)

• Japanese: JIS G3445 (Cold drawn carbon steel tubes for mechanical applications)

• Chinese: GB/T 3639 (Precision steel tubes — cold drawn or cold rolled)

7. Applications

7.1 General Application Areas

• Automotive components

• Hydraulic and pneumatic cylinders

• Mechanical engineering assemblies

• Precision machining parts

• Structural frameworks

7.2 Specific Uses

• Automotive: Drive shafts, axle components, steering linkages

• Hydraulics: Cylinder barrels, piston rods, valve bodies

• Machinery: Gear shafts, spindles, couplings

• General Engineering: Fixtures, jigs, frame supports

• Precision Devices: Instrument housings, hydraulic fittings

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.

Who We are ?

-------A professional steel pipes materials inventor, manufacturer and solution provider
Torich International Limited is a professional manufacturer and exporter of steel pipes materials. It is an international marketing and sales company specialized in steel tubes, which holds the factories of Seamless Steel Tubes with Carbon and Alloy Steel Grade, Welded Precision Steel Tubes,DOM Steel Tubes, Seamless & Welded Stainless Steel Tubes with Nickel and Alloy Steel Grade.
Our factory was established since 1997, with the name of TORICH INTERNATIONAL LIMITED. The factories’ technicians are of great engineering experience in steel pipe industry for more than 20 years, which are in great command of production technology for Cold Drawing and Cold Rolling. So we have strong technician team and manufacturing capability.

What products we do?

------- Invent and produce various Precision Steel Pipes

Our steel pipes cover the following ranges:
Seamless Precision Steel Pipes

Bearing Steel Tubes
Welded Precision Steel Pipes, with DOM production
Seamless Heat Exchanger Steel Pipe
Seamless Boiler Steel Pipes

Honed Tubes

Hydraulic Cylinder Steel Tubes

Hydraulic Telescopic Cylinder Tubes
Seamless Structural Steel Pipes
Seamless Mechanical Steel Pipes
Seamless Alloy Steel Tubes & Pipes
Seamless Stainless Steel tubes
Welded Stainless Steel Tubes
Seamless Stainless Steel Tubes & Pipes
Welded Stainless Steel Tubes & Pipes
Seamless Carbon Steel Tubes & Pipes
Nickel Alloy Steel Tubes & Pipes

What TORICH do:
1. Producing Steel Tubes
2. Selling both on Domestic and International Market
3. Precisely Targeting Customers’ Requirement- Sourcing the right factory for right products for Customers

Products Application:
Oil Cylinders
Air Cylinder, 
Automotive Cylinder Liners
Boilers, Pressure Vessels
Shell & Heat Exchangers
Jack Lifting
Telescopic Systems
Pneumatic Cylinders
Agricultural Machineries

Size range is: 
O.D. 4-350mm, 
W.T. 0.5-30mm, 
Length: according to customer’s requirement and agreement
 

Steel Grade:
Carbon Steel Grade:
ST35.8, ST37.0, ST44, ST52;
E155, E195, E215, E235, E275, E355;
195GH, P235GH, P265GH, P195TR1, P195TR2, P235TR1, P235TR2, P265TR1, P265TR2;
SAE1010, SAE1020, SAE1026, SAE1035, SAE1045;

Carbon steel tube: SA178, A179, A192, A210, SA213, SA214, etc.
Alloy Steel Grade:
T2, T5, T9, T11, T12, T17, T21, T22, T91,T92, 15Mo3,16Mo3, 13CrMo44;
SAE4130, SAE4140, 40Cr, 40Cr4, 10CrMo910, 12CrMo910, 11CrMo910,
25CrMo4, 35CrMo, 35CrMo4, 42CrMo4, 34CrMo4, 20MnV, 20MnV6,20CrMn;
Carbon steel tube: A179,A192,A210,DIN17175,etc.

Bearing Steel Grades:
GCr15 52100 suj2 suj3 100Cr6 SKF3S SKF3S 20CrNiMo 8620H 4118H;

Nickel Alloy Grade:
N02200/2201, N04400, N06600, N06601, N06625, N06852, N06219, N06690, N08800/8810/8811, N08825, N08028, N08535, N08904, N08925, N08926, N010276, N06022, etc.

Austenitic/Super Austenitic Stainless Steel Grade:
304/304L, 316/316L, 314, 321, 347H, 316Ti, 316LMod, 317L/N, 310S, 253MA, 330, 904L, S31254, XM-19, etc. 

Ferrite/Martensite Stainless Steel Grade:
TP410, TP405, TP420, TP430, TP430Ti, TP403, TP409, TP444, TP439, TP446, etc. 

Duplex/Super Duplex Stainless Steel Grade:
S31803, S32304, S31500, S32550, S32750, S32760, etc. 
Corporate Culture:
We focus on Quality First, Quality Traceability, and Quality Stability!
We focus on Customer First, People First, and Quality-Oriented!
Success:
First factory started in 1997, in the name of Torich , now covers 50000 square meters of factory building, with more than 100employees, and over 45 million RBM assets.
In 2008, we started the company of Torich International Limited for international business and marketing.
Welcome partners from all over the world for long term cooperation!