CDW Pipe (Small Diameter) — Cold Drawn Welded Precision Steel Tube for Automotive Parts

Material

This product is a Cold Drawn Welded (CDW) precision steel tube: steel strip is formed and welded into a tube, then cold drawn to achieve high dimensional accuracy, better concentricity, and a smoother surface—ideal for automotive components that require stable fit-up, repeatable forming, and consistent mechanical performance.

Specifications

• Type: Welded cold drawn precision tube (CDW)

• Size focus: Small diameter (typical automotive ranges; custom available)

• Order dimensions: OD/ID, OD/WT, or ID/WT (as required)

• Delivery conditions (select per application): +C, +LC, +SR, +A, +N

• Surface finish: Smooth inner/outer surfaces; standard maximum surface roughness requirement can be specified

• Inspection: Dimensional checks, tensile testing, visual inspection; optional roughness reporting and NDT can be specified

• Corrosion protection & packaging: Temporary corrosion protection is typically supplied unless otherwise agreed

Key Features

• Precision OD/ID & wall control for automated assembly and tight-fit parts

• Improved surface quality after cold drawing, supporting low-friction motion parts and clean forming

• Stable mechanical properties selectable by delivery condition (+SR / +N commonly chosen for balanced strength and formability)

• Good weldability and formability for bending, expanding, flaring, and subsequent fabrication

Our Advantages 

1. “Can you hold tight tolerances and surface requirements for robotic/automated assembly?”
   Yes. Precision applications are supported by defined tolerance systems and a specified maximum surface roughness requirement; additional roughness measurement/reporting can also be agreed.

2. “How do you ensure weld seam integrity and prevent hidden defects?”
   We can supply tubes with non-destructive testing (NDT) as specified (e.g., eddy current testing for longitudinal imperfections and leak-tightness verification). Eddy current principles and acceptance-based inspection are widely used for welded tube quality control.

3. “Do you provide full traceability and inspection certificates for audits?”
   Yes. We support EN 10204 inspection documents (e.g., 3.1/3.2 as required) and can maintain heat/lot traceability through marking options (including cast/heat identification when specified).

Chemical Composition

Mechanical Properties 

Standards

• ASTM: ASTM A513 (ERW mechanical tubing; CDW/DOM-type finishing specified by type/requirement)

• EN: EN 10305-2 (welded cold drawn precision tubes; delivery conditions +C/+LC/+SR/+A/+N)

• GOST: GOST 10704 (electric-welded steel tubes; commonly referenced for welded tube supply chains)

• JIS: JIS G3445 (carbon steel tubes for machine structural purposes)

• GB: GB/T 24187 (cold-drawn precision single welded steel tubes)

Application Areas

Primary industries: Automotive, general engineering, machinery manufacturing, hydraulic/pneumatic-related assemblies, and precision structures.

Where it’s used in automotive (examples):

• Shock absorber / damper components (inner tubes, sleeves)

• Steering & chassis parts (spacers, sleeves, support tubes)

• Seat structures & safety sub-assemblies (precision structural tubes)

• Machined tubular parts requiring consistent ID/OD for press-fit, bushings, and bearing seats