Cold-Drawn Welded Tube

A cold-drawn welded tube begins as a welded mother tube and is then pulled through a die, with a plug or mandrel used when the bore must be controlled. The drawing pass reduces the section, improves geometry and creates a different product from an ordinary as-welded tube. It is a practical route when an OEM component needs a specific outside dimension, inside dimension, wall relationship or non-round profile.

When to Specify Cold Drawing

Choose this route when the drawing identifies functional datums, close fit, controlled concentricity, reduced machining allowance or a custom section that can be developed through tooling. The inquiry should state which dimension controls the part. Applying tight tolerances to outside diameter, inside diameter and wall simultaneously may be impractical, so Tenjan reviews the tolerance chain before confirming production.

Mechanical Condition and Fabrication

Cold work raises strength and hardness while reducing ductility. State whether the tube will be supplied as drawn, stress relieved, annealed or in another agreed condition. If the component will be bent, flared, welded, machined or plated, include those operations so the delivery condition and surface protection can be planned around the finished process.

Quality Planning

The welded mother tube, weld integrity, drawing reduction, dimensional inspection and final surface all form part of the control plan. Define required testing, certificate, heat and batch traceability, inspection sample rate and packing in the initial RFQ. For a new custom profile, use first-article measurements and an assembly trial before repeat production.