PROCESSING SPECIFICATION
Sizes, Grades and Checks for Cold Drawing
What we run today, and what we check on every lot.
| Scope | Typical range / requirement | Output | Checks / records |
|---|---|---|---|
| Input size | Round bar suitable for reduction | Drawn bar Ø 8–90 mm | Diameter · straightness |
| Grades | C20 · C45 · 16MnCr5 · 42CrMo4 · 100Cr6 | Drawn condition by order | Grade · hardness as specified |
| Control | EN 10278 · h9–h11 | Finished dimensions | Size · surface · certificate |
How We Do It
Hot rolled round bar in the right grade, descaled and prepared for the die.
Cold Drawing
Drawn bar at the agreed size, h9–h11, with a bright finish.
- Prepare the bar. We descale and clean the hot rolled bar so the die gets a sound surface.
- Draw through the die. The bar is pulled through a die smaller than its starting diameter, in one or more passes.
- Straighten and cut to length.
- Inspect diameter, straightness and surface, then certify the heat.
Why Use Cold Drawing?
Drawing gives a tighter size, a cleaner surface and a stronger bar than hot rolling. Parts run on your machine with less allowance to cut away.
When Should You Choose It?
Choose cold drawn bar when you want h9–h11 size control and a bright finish without grinding. If you need a tighter tolerance than h9, ask for ground bar. If your part needs the surface skin of the hot rolled bar removed, ask for peeled bar. The three finishes sit side by side under bright bar manufacturing.
Common Questions
What is the cold drawing process?
Cold drawing pulls a hot rolled bar through a die at room temperature. The die reduces the diameter, fixes the size and leaves a bright surface. The bar leaves the die stronger and harder than it went in.
What is cold drawn steel?
Cold drawn steel is steel bar that has been drawn through a die without heating. It has a tighter size tolerance, a smoother surface and a higher strength than the hot rolled bar it started as.
Cold drawn steel vs hot rolled: what is the difference?
Hot rolled bar has a rough scaled surface and a loose size tolerance. Cold drawn bar is bright, closer to size and stronger. It costs more per tonne and saves machining time and material.
Cold drawn steel vs cold rolled: is there a difference?
Both are cold worked at room temperature. "Cold rolled" usually means flat products such as sheet and coil. "Cold drawn" is the term for bar and wire pulled through a die.
Why is cold drawn steel stronger than hot rolled?
Pulling the bar through the die deforms the grain structure and work hardens the steel. That raises yield strength and hardness. The trade-off is lower ductility.
What tolerance does cold drawn bar hold?
OneKaizen supplies drawn bar to h9–h11 under EN 10278. For a Ø 20 mm bar, h9 allows 0 to −0.052 mm and h11 allows 0 to −0.130 mm.
What sizes and grades can you draw?
OneKaizen draws round bar from Ø 8 to 90 mm in carbon and alloy steels such as C20, C45, 16MnCr5, 42CrMo4 and 100Cr6.
What do I send for a quote?
Send us the grade, starting and finished diameter, tolerance, length and quantity. A drawing helps. We come back with the route, inspection plan and delivery date.