Application description

Widely used in hydraulic and pneumatic cylinders, automotive components (shock absorbers, steering columns, drive shafts), bearings, and precision machinery parts. Also suitable for instrumentation tubes, medical devices, aerospace structures, and high-pressure fluid lines. The tight tolerances and excellent surface finish make it ideal for critical applications requiring consistent performance and reliability.

Production description

Seamless or welded steel tube is pickled, cold drawn through precision dies to target OD and wall thickness, then stress-relieved in annealing furnaces. Multiple passes with intermediate annealing ensure tight tolerances. The tube is then straightened, cut, inspected for dimensional accuracy and surface finish, and oiled.

Shipping Packaging

For export, precision steel tubes are bundled with interleaved separators, fitted with plastic end caps, wrapped with VCI paper and moisture-proof polyethylene, packed on ISPM-15 pallets, secured with steel straps, and protected with edge protectors. Labels include grade, dimensions, tolerances, and heat number for safe sea freight.

Why Choose Us?

1.Factory Strength:Direct manufacturer with precision cold drawing lines, multiple-pass drawing capabilities, stress-relieving annealing furnaces, and straightening equipment, producing seamless and welded precision tubes with OD 4–160mm and wall 0.5–25mm to ISO/EN/ASTM standards.

2.Quality Assurance:Strict control of dimensional tolerances (OD ±0.02mm, wall ±0.03mm), straightness (≤0.2mm/m), surface roughness (Ra ≤0.8µm), and mechanical properties; 100% eddy current or ultrasonic testing; compliant with DIN 2391, EN 10305, ASTM A519, GB/T 3639.

3.Certifications & Reports:Mill test certificates (MTC) with each shipment; third-party inspections (SGS, BV) and test reports (tensile, hardness, flaring, flattening) available upon request.

4.Customization & Service:Wide material range (carbon steel 10#–45#, ST52; alloy steel 15CrMo, 4140; stainless steel 304/316L), custom tolerances (up to ±0.01mm), lengths up to 15m, surface finishes (bright, polished, pickled), and tempers (annealed, 1/4–1/2 hard, hard) with fast lead times.

5.Export Packaging:Interleaved separators + plastic end caps + VCI paper + moisture-proof polyethylene + ISPM-15 pallets + steel strapping + edge protectors + clear labeling for safe sea freight and corrosion prevention.

FAQ

1. How to store precision steel tubes to prevent rust and surface damage?  

Store in dry, clean indoor area on wooden pallets, keep original VCI paper and moisture-proof wrapping intact. Avoid contact with water, oils, or corrosive chemicals. For long-term storage, maintain humidity below 60%. Do not remove plastic end caps until installation to prevent internal contamination.

2. What is the difference between cold drawn seamless (CDS) and cold drawn welded (CDW) precision tubes?  

CDS tubes have no weld seam, offering higher pressure rating, uniform wall thickness, and better concentricity, ideal for hydraulic cylinders and high-pressure applications. CDW tubes start from welded tube then cold drawn, are more economical and suitable for lower-pressure precision applications like shock absorbers and telescopic parts. Both achieve tight tolerances.

3. Can precision steel tubes be further machined (cut, drilled, threaded) without losing accuracy?  

Yes. Use sharp carbide tools, proper lubrication, and secure clamping to maintain tube geometry. For tight-tolerance applications, allow for slight material springback. We can also supply semi-finished tubes (cut-to-length, chamfered, deburred) to reduce your machining steps. Avoid excessive heat during machining to maintain dimensional stability.